ST72324B 5V RANGE 8-BIT MCU WITH 8 TO 32K FLASH/ROM, 10-BIT ADC, 4 TIMERS, SPI, SCI INTERFACE ■ ■ ■ ■ ■ Memories – 8 to 32K dual voltage High Density Flash (HDFlash) or ROM with read-out protection capability. In-Application Programming and InCircuit Programming for HDFlash devices – 384 to 1K bytes RAM – HDFlash endurance: 100 cycles, data retention: 40 years at 85°C Clock, Reset And Supply Management – Enhanced low voltage supervisor (LVD) for main supply with programmable reset thresholds and auxiliary voltage detector (AVD) with interrupt capability – Clock sources: crystal/ceramic resonator oscillators, internal RC oscillator, clock security system and bypass for external clock – PLL for 2x frequency multiplication – Four Power Saving Modes: Halt, Active-Halt, Wait and Slow Interrupt Management – Nested interrupt controller – 10 interrupt vectors plus TRAP and RESET – 9/6 external interrupt lines (on 4 vectors) Up to 32 I/O Ports – 32/24 multifunctional bidirectional I/O lines – 22/17 alternate function lines – 12/10 high sink outputs 4 Timers – Main Clock Controller with: Real time base, Beep and Clock-out capabilities – Configurable watchdog timer – 16-bit Timer A with: 1 input capture, 1 output compare, external clock input, PWM and pulse generator modes – 16-bit Timer B with: 2 input captures, 2 output compares, PWM and pulse generator modes TQFP32 7x7 TQFP44 10 x 10 SDIP42 600 mil ■ ■ SDIP32 400 mil 2 Communication Interfaces – SPI synchronous serial interface – SCI asynchronous serial interface 1 Analog Peripheral (low current coupling) – 10-bit ADC with up to 12 robust input ports ■ Instruction Set – 8-bit Data Manipulation – 63 Basic Instructions – 17 main Addressing Modes – 8 x 8 Unsigned Multiply Instruction ■ Development Tools – Full hardware/software development package – In-Circuit Testing capability Device Summary ST72F324B(J/K)6 ST72F324B(J/K)4 ST72F324B(J/K)2 ST72324B(J/K)6 ST72324B(J/K)4 ST72324B(J/K)2 Feature Program memory Flash 32K Flash 16K Flash 8K ROM 32K ROM 16K ROM 8K bytes RAM (stack) - bytes 1024 (256) 512 (256) 384 (256) 1024 (256) 512 (256) 384 (256) Voltage Range 3.8V to 5.5V Temp. Range up to -40°C to +125°C Packages SDIP42, TQFP44 10x10,SDIP32, TQFP32 7x7 For information on ordering older ST72F324(J/K) devices, refer to the separate datasheet Rev. 5 February 2006 1/167 1 Table of Contents 1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2 PIN DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3 REGISTER & MEMORY MAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4 FLASH PROGRAM MEMORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.2 MAIN FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.3 STRUCTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.4 4.3.1 Read-out Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 ICC INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.5 ICP (IN-CIRCUIT PROGRAMMING) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4.6 IAP (IN-APPLICATION PROGRAMMING) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4.7 RELATED DOCUMENTATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4.7.1 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 5 CENTRAL PROCESSING UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 5.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 5.2 MAIN FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 5.3 CPU REGISTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 6 SUPPLY, RESET AND CLOCK MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 6.1 PHASE LOCKED LOOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 6.2 MULTI-OSCILLATOR (MO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 6.3 RESET SEQUENCE MANAGER (RSM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 6.3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.2 Asynchronous External RESET pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.3 External Power-On RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.4 Internal Low Voltage Detector (LVD) RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.5 Internal Watchdog RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4 SYSTEM INTEGRITY MANAGEMENT (SI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 25 26 26 26 27 6.4.1 Low Voltage Detector (LVD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.2 Auxiliary Voltage Detector (AVD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.3 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.4 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 INTERRUPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 28 29 30 31 31 7.2 MASKING AND PROCESSING FLOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 7.3 INTERRUPTS AND LOW POWER MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 7.4 CONCURRENT & NESTED MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 7.5 INTERRUPT REGISTER DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 7.6 EXTERNAL INTERRUPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 7.6.1 I/O Port Interrupt Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 7.7 EXTERNAL INTERRUPT CONTROL REGISTER (EICR) . . . . . . . . . . . . . . . . . . . . . . . 38 8 POWER SAVING MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 8.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 . . . . 40 8.2 SLOW MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 8.3 WAIT MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 2/167 2 Table of Contents 8.4 ACTIVE-HALT AND HALT MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 8.4.1 ACTIVE-HALT MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4.2 HALT MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 I/O PORTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 42 43 45 45 FUNCTIONAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 9.2.1 Input Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2.2 Output Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2.3 Alternate Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.3 I/O PORT IMPLEMENTATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 45 45 48 9.4 LOW POWER MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 9.5 INTERRUPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 9.5.1 I/O Port Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 10 ON-CHIP PERIPHERALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 10.1 WATCHDOG TIMER (WDG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 10.1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1.2 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1.3 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1.4 How to Program the Watchdog Timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1.5 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1.6 Hardware Watchdog Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1.7 Using Halt Mode with the WDG (WDGHALT option) . . . . . . . . . . . . . . . . . . . . . . . 10.1.8 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1.9 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2 MAIN CLOCK CONTROLLER WITH REAL TIME CLOCK AND BEEPER (MCC/RTC) . 51 51 51 52 54 54 54 54 54 56 10.2.1 Programmable CPU Clock Prescaler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.2 Clock-out Capability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.3 Real Time Clock Timer (RTC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.4 Beeper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.5 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.7 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3 16-BIT TIMER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 56 56 56 57 57 57 59 10.3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3.2 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3.3 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3.4 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3.5 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3.6 Summary of Timer modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3.7 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.4 SERIAL PERIPHERAL INTERFACE (SPI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 59 59 71 71 71 72 78 10.4.1 10.4.2 10.4.3 10.4.4 10.4.5 10.4.6 3/167 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clock Phase and Clock Polarity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 .... Error Flags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 78 78 82 83 85 Table of Contents 10.4.7 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 10.4.8 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 10.5 SERIAL COMMUNICATIONS INTERFACE (SCI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 10.5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 10.5.2 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 10.5.3 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 10.5.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 10.5.5 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 10.5.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 10.5.7 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 10.6 10-BIT A/D CONVERTER (ADC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 10.6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.6.2 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.6.3 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.6.4 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.6.5 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.6.6 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 INSTRUCTION SET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 CPU ADDRESSING MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 105 106 106 106 107 109 109 11.1.1 Inherent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1.2 Immediate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1.3 Direct . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1.4 Indexed (No Offset, Short, Long) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1.5 Indirect (Short, Long) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1.6 Indirect Indexed (Short, Long) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1.7 Relative mode (Direct, Indirect) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2 INSTRUCTION GROUPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 110 110 110 110 111 111 112 12 ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 12.1 PARAMETER CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 12.1.1 Minimum and Maximum values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1.2 Typical values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1.3 Typical curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1.4 Loading capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1.5 Pin input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2 ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 115 115 115 115 116 12.2.1 Voltage Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2.2 Current Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2.3 Thermal Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.3 OPERATING CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 116 117 117 12.3.1 Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 12.4 LVD/AVD CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 12.4.1 Operating Conditions with Low Voltage Detector (LVD) . . . . . . . . . . . . . . . . . . . . 118 12.4.2 Auxiliary Voltage Detector (AVD) Thresholds . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 12.5 SUPPLY CURRENT CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 12.5.1 ROM CURRENT CONSUMPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 . . . 119 12.5.2 FLASH CURRENT CONSUMPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 12.5.3 Supply and Clock Managers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 4/167 1 Table of Contents 12.5.4 On-Chip Peripherals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 12.6 CLOCK AND TIMING CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 12.6.1 General Timings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.6.2 External Clock Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.6.3 Crystal and Ceramic Resonator Oscillators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.6.4 RC Oscillators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.6.5 PLL Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.7 MEMORY CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 123 124 127 128 129 12.7.1 RAM and Hardware Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 12.7.2 FLASH Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 12.8 EMC CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 12.8.1 Functional EMS (Electro Magnetic Susceptibility) . . . . . . . . . . . . . . . . . . . . . . . . 12.8.2 Electro Magnetic Interference (EMI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.8.3 Absolute Maximum Ratings (Electrical Sensitivity) . . . . . . . . . . . . . . . . . . . . . . . . 12.9 I/O PORT PIN CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 131 132 133 12.9.1 General Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 12.9.2 Output Driving Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 12.10 CONTROL PIN CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 12.10.1Asynchronous RESET Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 12.10.2ICCSEL/VPP Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 12.11 TIMER PERIPHERAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 12.11.116-Bit Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 12.12 COMMUNICATION INTERFACE CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . 141 12.12.1SPI - Serial Peripheral Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 12.13 10-BIT ADC CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 12.13.1Analog Power Supply and Reference Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.13.2General PCB Design Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.13.3ADC Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 PACKAGE CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.1 PACKAGE MECHANICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 145 146 147 147 13.2 THERMAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 13.3 SOLDERING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 14 ST72324B DEVICE CONFIGURATION AND ORDERING INFORMATION . . . . . . . . . . . . . . 151 14.1 FLASH OPTION BYTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 14.2 ROM DEVICE ORDERING INFORMATION AND TRANSFER OF CUSTOMER CODE 153 14.3 FLASH DEVICE ORDERING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 14.4 VERSION-SPECIFIC SALES CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 14.5 SILICON IDENTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 14.6 DEVELOPMENT TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 14.6.1 Socket and Emulator Adapter Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 14.7 ST7 APPLICATION NOTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 15 KNOWN LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 15.1 ALL FLASH AND ROM DEVICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 167 15.1.1 Safe Connection of OSC1/OSC2 Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 15.1.2 External interrupt missed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 15.1.3 Unexpected Reset Fetch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 5/167 1 Table of Contents 15.1.4 Clearing active interrupts outside interrupt routine . . . . . . . . . . . . . . . . . . . . . . . . 15.1.5 16-bit Timer PWM Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15.1.6 SCI Wrong Break duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15.2 8/16K FLASH DEVICES ONLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 164 164 165 15.2.1 39-Pulse ICC Entry Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 15.3 32K FLASH DEVICES ONLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 15.3.1 ADC Accuracy in 32K Flash Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 15.4 16K AND 8K ROM DEVICES ONLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 15.4.1 Read-Out Protection with LVD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 15.4.2 I/O Port A and F Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 15.5 32K ROM DEVICES ONLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 16 REVISION HISTORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 To obtain the most recent version of this datasheet, please check at www.st.com>products>technical literature>datasheet. Please also pay special attention to the Section “KNOWN LIMITATIONS” on page 162. 6/167 1 167 ST72324B 1 INTRODUCTION The ST72F324B and ST72324B devices are members of the ST7 microcontroller family designed for the 5V operating range. – The 32-pin devices are designed for mid-range applications – The 42/44-pin devices target the same range of applications requiring more than 24 I/O ports. All devices are based on a common industrystandard 8-bit core, featuring an enhanced instruction set and are available with FLASH or ROM program memory. Under software control, all devices can be placed in WAIT, SLOW, ACTIVE-HALT or HALT mode, reducing power consumption when the application is in idle or stand-by state. The enhanced instruction set and addressing modes of the ST7 offer both power and flexibility to software developers, enabling the design of highly efficient and compact application code. In addition to standard 8-bit data management, all ST7 microcontrollers feature true bit manipulation, 8x8 unsigned multiplication and indirect addressing modes. Figure 1. Device Block Diagram 8-BIT CORE ALU RESET VPP PROGRAM MEMORY (8K - 60K Bytes) CONTROL RAM (384 - 1024 Bytes) VSS VDD LVD OSC1 OSC2 OSC WATCHDOG PORT F PF7:6,4,2:0 (6 bits on J devices) (5 bits on K devices) TIMER A BEEP ADDRESS AND DATA BUS MCC/RTC/BEEP PORT A PA7:3 (5 bits on J devices) (4 bits on K devices) PORT B PB4:0 (5 bits on J devices) (3 bits on K devices) PORT E PE1:0 (2 bits) PORT C SCI TIMER B PC7:0 (8 bits) PORT D PD5:0 (6 bits on J devices) (2 bits on K devices) SPI 10-BIT ADC VAREF VSSA 7/167 3 ST72324B 2 PIN DESCRIPTION PE0 / TDO VDD_2 OSC1 OSC2 VSS_2 RESET VPP / ICCSEL PA7 (HS) PA6 (HS) PA5 (HS) PA4 (HS) Figure 2. 42-Pin SDIP and 44-Pin TQFP Package Pinouts 44 43 42 41 40 39 38 37 36 35 34 1 33 2 32 3 31 ei0 ei2 4 30 5 29 ei3 6 28 7 27 8 26 9 25 ei1 10 24 11 23 12 13 14 15 16 17 18 19 20 21 22 VSS_1 VDD_1 PA3 (HS) PC7 / SS / AIN15 PC6 / SCK / ICCCLK PC5 / MOSI / AIN14 PC4 / MISO / ICCDATA PC3 (HS) / ICAP1_B PC2 (HS) / ICAP2_B PC1 / OCMP1_B / AIN13 PC0 / OCMP2_B / AIN12 AIN5 / PD5 VAREF VSSA MCO / AIN8 / PF0 BEEP / (HS) PF1 (HS) PF2 OCMP1_A / AIN10 / PF4 ICAP1_A / (HS) PF6 EXTCLK_A / (HS) PF7 VDD_0 VSS_0 RDI / PE1 PB0 PB1 PB2 PB3 (HS) PB4 AIN0 / PD0 AIN1 / PD1 AIN2 / PD2 AIN3 / PD3 AIN4 / PD4 (HS) PB4 AIN0 / PD0 AIN1 / PD1 AIN2 / PD2 AIN3 / PD3 AIN4 / PD4 AIN5 / PD5 VAREF VSSA MCO / AIN8 / PF0 BEEP / (HS) PF1 (HS) PF2 AIN10 / OCMP1_A / PF4 ICAP1_A / (HS) PF6 EXTCLK_A / (HS) PF7 AIN12 / OCMP2_B / PC0 AIN13 / OCMP1_B / PC1 ICAP2_B/ (HS) PC2 ICAP1_B / (HS) PC3 ICCDATA / MISO / PC4 AIN14 / MOSI / PC5 1 ei3 2 3 4 5 6 7 8 9 10 11 ei1 12 13 14 15 16 17 18 19 20 21 ei2 ei0 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 PB3 PB2 PB1 PB0 PE1 / RDI PE0 / TDO VDD_2 OSC1 OSC2 VSS_2 RESET VPP / ICCSEL PA7 (HS) PA6 (HS) PA5 (HS) PA4 (HS) VSS_1 VDD_1 PA3 (HS) PC7 / SS / AIN15 PC6 / SCK / ICCCLK (HS) 20mA high sink capability eix associated external interrupt vector 8/167 ST72324B PIN DESCRIPTION (Cont’d) Figure 3. 32-Pin SDIP Package Pinout (HS) PB4 1 ei3 32 ei2 PB3 AIN0 / PD0 2 31 PB0 AIN1 / PD1 3 30 PE1 / RDI VAREF 4 29 PE0 / TDO VSSA 5 28 VDD_2 MCO / AIN8 / PF0 6 27 OSC1 BEEP / (HS) PF1 7 26 OSC2 OCMP1_A / AIN10 / PF4 8 25 VSS_2 ICAP1_A / (HS) PF6 9 24 RESET ei1 EXTCLK_A / (HS) PF7 10 23 VPP / ICCSEL AIN12 / OCMP2_B / PC0 11 22 PA7 (HS) AIN13 / OCMP1_B / PC1 12 21 PA6 (HS) ICAP2_B / (HS) PC2 13 20 PA4 (HS) ICAP1_B / (HS) PC3 14 ICCDATA/ MISO / PC4 AIN14 / MOSI / PC5 19 PA3 (HS) 15 18 PC7 / SS / AIN15 16 17 PC6 / SCK / ICCCLK ei0 (HS) 20mA high sink capability eix associated external interrupt vector PD1 / AIN1 PD0 / AIN0 PB4 (HS) PB3 PB0 PE1 / RDI PE0 / TDO VDD_2 Figure 4. 32-Pin TQFP 7x7 Package Pinout 32 31 30 29 28 27 26 25 24 1 ei3 ei2 23 2 22 3 ei1 21 4 20 5 19 6 18 7 ei0 17 8 9 10 11 12 13 14 15 16 AIN13 / OCMP1_B / PC1 ICAP2_B / (HS) PC2 ICAP1_B / (HS) PC3 ICCDATA / MISO / PC4 AIN14 / MOSI / PC5 ICCCLK / SCK / PC6 AIN15 / SS / PC7 (HS) PA3 VAREF VSSA MCO / AIN8 / PF0 BEEP / (HS) PF1 OCMP1_A / AIN10 / PF4 ICAP1_A / (HS) PF6 EXTCLK_A / (HS) PF7 AIN12 / OCMP2_B / PC0 OSC1 OSC2 VSS_2 RESET VPP / ICCSEL PA7 (HS) PA6 (HS) PA4 (HS) (HS) 20mA high sink capability eix associated external interrupt vector 9/167 1 ST72324B PIN DESCRIPTION (Cont’d) For external pin connection guidelines, refer to See “ELECTRICAL CHARACTERISTICS” on page 115. Legend / Abbreviations for Table 1: Type: I = input, O = output, S = supply Input level: A = Dedicated analog input In/Output level: C = CMOS 0.3VDD/0.7VDD CT= CMOS 0.3VDD/0.7VDD with input trigger Output level: HS = 20mA high sink (on N-buffer only) Port and control configuration: – Input: float = floating, wpu = weak pull-up, int = interrupt 1), ana = analog ports – Output: OD = open drain 2), PP = push-pull Refer to “I/O PORTS” on page 45 for more details on the software configuration of the I/O ports. The RESET configuration of each pin is shown in bold. This configuration is valid as long as the device is in reset state. Table 1. Device Pin Description 1 30 1 PB4 (HS) I/O CT HS X X Port B4 7 2 31 2 PD0/AIN0 X X X X X Port D0 ADC Analog Input 0 8 3 32 3 PD1/AIN1 I/O CT I/O CT X X X X X Port D1 ADC Analog Input 1 9 4 PD2/AIN2 X X X X X Port D2 ADC Analog Input 2 10 5 PD3/AIN3 I/O CT I/O CT X X X X X Port D3 ADC Analog Input 3 11 6 PD4/AIN4 I/O CT X X X X X Port D4 ADC Analog Input 4 12 7 PD5/AIN5 I/O CT S X X X X X Port D5 ADC Analog Input 5 13 8 1 4 VAREF 14 9 2 5 VSSA 15 10 3 6 PF0/MCO/AIN8 16 11 4 7 17 12 X Alternate Function PP ana int wpu ei3 Analog Reference Voltage for ADC S Analog Ground Voltage I/O CT X ei1 X ADC Analog Input 8 X X Port F0 Main clock out (fCPU) Beep signal output PF1 (HS)/BEEP I/O CT HS X ei1 X X Port F1 PF2 (HS) I/O CT HS X ei1 X X Port F2 X X Port F4 Timer A OutADC Analog put ComInput 10 pare 1 18 13 5 8 PF4/OCMP1_A/ AIN10 I/O CT 19 14 6 9 PF6 (HS)/ICAP1_A I/O CT PF7 (HS)/ EXTCLK_A I/O CT 20 15 7 10 Input float Pin Name OD 6 SDIP32 Output Main function Output (after reset) Input Port SDIP42 Type Level TQFP44 TQFP32 Pin n° X X X HS X X X X Port F6 Timer A Input Capture 1 HS X X X X Port F7 Timer A External Clock Source 21 VDD_0 S Digital Main Supply Voltage 22 VSS_0 S Digital Ground Voltage 23 16 8 11 PC0/OCMP2_B/ AIN12 10/167 1 I/O CT X X X X X Port C0 Timer B OutADC Analog put ComInput 12 pare 2 ST72324B Alternate Function PP X Main function Output (after reset) OD X ana X int Input wpu Output I/O CT Port float PC1/OCMP1_B/ AIN13 Type SDIP32 TQFP32 SDIP42 TQFP44 24 17 9 12 Pin Name Input Level Pin n° X X Port C1 Timer B OutADC Analog put ComInput 13 pare 1 25 18 10 13 PC2 (HS)/ICAP2_B I/O CT HS X X X X Port C2 Timer B Input Capture 2 26 19 11 14 PC3 (HS)/ICAP1_B I/O CT HS X X X X Port C3 Timer B Input Capture 1 PC4/MISO/ICCDATA I/O CT X X X X Port C4 SPI Master In / Slave Out Data ICC Data Input 28 21 13 16 PC5/MOSI/AIN14 I/O CT X X X X Port C5 SPI Master Out / Slave In Data ADC Analog Input 14 29 22 14 17 PC6/SCK/ICCCLK I/O CT X X X X Port C6 SPI Serial Clock ICC Clock Output 30 23 15 18 PC7/SS/AIN15 I/O CT X X X X Port C7 SPI Slave Select (active low) ADC Analog Input 15 31 24 16 19 PA3 (HS) I/O CT X X Port A3 27 20 12 15 HS X X X ei0 32 25 VDD_1 S Digital Main Supply Voltage 33 26 VSS_1 S Digital Ground Voltage 34 27 17 20 PA4 (HS) I/O CT HS X X X X Port A4 35 28 PA5 (HS) I/O CT HS X X X X Port A5 36 29 18 21 PA6 (HS) I/O CT HS X T Port A6 1) 37 30 19 22 PA7 (HS) I/O CT HS X T Port A7 1) 38 31 20 23 VPP /ICCSEL Must be tied low. In the flash programming mode, this pin acts as the programming voltage input VPP. See Section 12.10.2 for more details. High voltage must not be applied to ROM devices. I I/O CT S Digital Ground Voltage O Resonator oscillator inverter output 42 35 24 27 OSC1 I External clock input or Resonator oscillator inverter input 43 36 25 28 VDD_2 44 37 26 29 PE0/TDO S Digital Main Supply Voltage I/O CT X X X X Port E0 SCI Transmit Data Out 1 38 27 30 PE1/RDI I/O CT X X X X Port E1 SCI Receive Data In 2 39 28 31 PB0 I/O CT X ei2 X X Port B0 Caution: Negative current injection not allowed on this pin5) 3 40 PB1 X ei2 X X Port B1 4 41 PB2 I/O CT I/O CT X ei2 5 42 29 32 PB3 I/O CT X 39 32 21 24 RESET 40 33 22 25 VSS_2 41 34 23 26 OSC2 Top priority non maskable interrupt. ei2 X X Port B2 X X Port B3 11/167 1 ST72324B Notes: 1. In the interrupt input column, “eiX” defines the associated external interrupt vector. If the weak pull-up column (wpu) is merged with the interrupt column (int), then the I/O configuration is pull-up interrupt input, else the configuration is floating interrupt input. 2. In the open drain output column, “T” defines a true open drain I/O (P-Buffer and protection diode to VDD are not implemented). See See “I/O PORTS” on page 45. and Section 12.9 I/O PORT PIN CHARACTERISTICS for more details. 3. OSC1 and OSC2 pins connect a crystal/ceramic resonator, or an external source to the on-chip oscillator; see Section 1 INTRODUCTION and Section 12.6 CLOCK AND TIMING CHARACTERISTICS for more details. 4. On the chip, each I/O port has 8 pads. Pads that are not bonded to external pins are in input pull-up configuration after reset. The configuration of these pads must be kept at reset state to avoid added current consumption. 5. For details refer to Section 12.9.1 on page 133 12/167 1 ST72324B 3 REGISTER & MEMORY MAP As shown in Figure 5, the MCU is capable of addressing 64K bytes of memories and I/O registers. The available memory locations consist of 128 bytes of register locations, up to 1024 bytes of RAM and up to 32 Kbytes of user program memory. The RAM space includes up to 256 bytes for the stack from 0100h to 01FFh. The highest address bytes contain the user reset and interrupt vectors. IMPORTANT: Memory locations marked as “Reserved” must never be accessed. Accessing a reseved area can have unpredictable effects on the device. Figure 5. Memory Map 0000h 007Fh 0080h HW Registers (see Table 2) 047Fh 0480h Reserved 7FFFh 8000h Program Memory (32K, 16K or 8K) FFFFh Short Addressing RAM (zero page) 00FFh 0100h RAM (1024, 512 or 384 Bytes) FFDFh FFE0h 0080h Interrupt & Reset Vectors (see Table 8) 256 Bytes Stack 01FFh 0200h 16-bit Addressing RAM 027Fh or 047Fh 8000h C000h 32 KBytes 16 KBytes E000h 8 Kbytes FFFFh 13/167 1 ST72324B Table 2. Hardware Register Map Register Label Block 0000h 0001h 0002h Port A 2) PADR PADDR PAOR Port A Data Register Port A Data Direction Register Port A Option Register 00h1) 00h 00h R/W R/W R/W 0003h 0004h 0005h 2) PBDR PBDDR PBOR Port B Data Register Port B Data Direction Register Port B Option Register 00h1) 00h 00h R/W R/W R/W PCDR PCDDR PCOR Port C Data Register Port C Data Direction Register Port C Option Register 00h1) 00h 00h R/W R/W R/W Port D 2) PDADR PDDDR PDOR Port D Data Register Port D Data Direction Register Port D Option Register 00h1) 00h 00h R/W R/W R/W 000Ch 000Dh 000Eh Port E 2) PEDR PEDDR PEOR Port E Data Register Port E Data Direction Register Port E Option Register 00h1) 00h 00h R/W R/W2) R/W2) 000Fh 0010h 0011h Port F 2) PFDR PFDDR PFOR Port F Data Register Port F Data Direction Register Port F Option Register 00h1) 00h 00h R/W R/W R/W 0006h 0007h 0008h 0009h 000Ah 000Bh Port B Port C 0012h to 0020h 0021h 0022h 0023h 0024h 0025h 0026h 0027h SPI ITC 0029h FLASH 002Ah WATCHDOG 002Bh SI 002Ch 002Dh MCC 14/167 1 Remarks Reserved Area (15 Bytes) 0028h 002Eh to 0030h Register Name Reset Status Address SPIDR SPICR SPICSR SPI Data I/O Register SPI Control Register SPI Control/Status Register xxh 0xh 00h R/W R/W R/W ISPR0 ISPR1 ISPR2 ISPR3 Interrupt Software Priority Register 0 Interrupt Software Priority Register 1 Interrupt Software Priority Register 2 Interrupt Software Priority Register 3 FFh FFh FFh FFh R/W R/W R/W R/W EICR External Interrupt Control Register 00h R/W FCSR Flash Control/Status Register 00h R/W WDGCR Watchdog Control Register 7Fh R/W SICSR System Integrity Control/Status register MCCSR MCCBCR Main Clock Control / Status Register Main Clock Controller: Beep Control Register Reserved Area (3 Bytes) 000x 000x b R/W 00h 00h R/W R/W ST72324B Address 0031h 0032h 0033h 0034h 0035h 0036h 0037h 0038h 0039h 003Ah 003Bh 003Ch 003Dh 003Eh 003Fh Block TIMER A Register Label TACR2 TACR1 TACSR TAIC1HR TAIC1LR TAOC1HR TAOC1LR TACHR TACLR TAACHR TAACLR TAIC2HR TAIC2LR TAOC2HR TAOC2LR 0040h 0041h 0042h 0043h 0044h 0045h 0046h 0047h 0048h 0049h 004Ah 004Bh 004Ch 004Dh 004Eh 004Fh 0050h 0051h 0052h 0053h 0054h 0055h 0056h 0057h 0073h 007Fh Timer A Control Register 2 Timer A Control Register 1 Timer A Control/Status Register3)4) Timer A Input Capture 1 High Register Timer A Input Capture 1 Low Register Timer A Output Compare 1 High Register Timer A Output Compare 1 Low Register Timer A Counter High Register Timer A Counter Low Register Timer A Alternate Counter High Register Timer A Alternate Counter Low Register Timer A Input Capture 2 High Register Timer A Input Capture 2 Low Register Timer A Output Compare 2 High Register Timer A Output Compare 2 Low Register Reset Status Remarks 00h 00h xxxx x0xxb xxh xxh 80h 00h FFh FCh FFh FCh xxh xxh 80h 00h R/W R/W R/W Read Only Read Only R/W R/W Read Only Read Only Read Only Read Only Read Only Read Only R/W R/W Reserved Area (1 Byte) TIMER B SCI TBCR2 TBCR1 TBCSR TBIC1HR TBIC1LR TBOC1HR TBOC1LR TBCHR TBCLR TBACHR TBACLR TBIC2HR TBIC2LR TBOC2HR TBOC2LR Timer B Control Register 2 Timer B Control Register 1 Timer B Control/Status Register Timer B Input Capture 1 High Register Timer B Input Capture 1 Low Register Timer B Output Compare 1 High Register Timer B Output Compare 1 Low Register Timer B Counter High Register Timer B Counter Low Register Timer B Alternate Counter High Register Timer B Alternate Counter Low Register Timer B Input Capture 2 High Register Timer B Input Capture 2 Low Register Timer B Output Compare 2 High Register Timer B Output Compare 2 Low Register 00h 00h xxxx x0xxb xxh xxh 80h 00h FFh FCh FFh FCh xxh xxh 80h 00h R/W R/W R/W Read Only Read Only R/W R/W Read Only Read Only Read Only Read Only Read Only Read Only R/W R/W SCISR SCIDR SCIBRR SCICR1 SCICR2 SCIERPR SCI Status Register SCI Data Register SCI Baud Rate Register SCI Control Register 1 SCI Control Register 2 SCI Extended Receive Prescaler Register Reserved area SCI Extended Transmit Prescaler Register C0h xxh 00h x000 0000h 00h 00h --00h Read Only R/W R/W R/W R/W R/W 00h 00h 00h R/W Read Only Read Only SCIETPR 0058h to 006Fh 0070h 0071h 0072h Register Name R/W Reserved Area (24 Bytes) ADC ADCCSR ADCDRH ADCDRL Control/Status Register Data High Register Data Low Register Reserved Area (13 Bytes) 15/167 1 ST72324B Legend: x=undefined, R/W=read/write Notes: 1. The contents of the I/O port DR registers are readable only in output configuration. In input configuration, the values of the I/O pins are returned instead of the DR register contents. 2. The bits associated with unavailable pins must always keep their reset value. 16/167 1 ST72324B 4 FLASH PROGRAM MEMORY 4.1 Introduction The ST7 dual voltage High Density Flash (HDFlash) is a non-volatile memory that can be electrically erased as a single block or by individual sectors and programmed on a Byte-by-Byte basis using an external VPP supply. The HDFlash devices can be programmed and erased off-board (plugged in a programming tool) or on-board using ICP (In-Circuit Programming) or IAP (In-Application Programming). The array matrix organisation allows each sector to be erased and reprogrammed without affecting other sectors. Depending on the overall Flash memory size in the microcontroller device, there are up to three user sectors (see Table 3). Each of these sectors can be erased independently to avoid unnecessary erasing of the whole Flash memory when only a partial erasing is required. The first two sectors have a fixed size of 4 Kbytes (see Figure 6). They are mapped in the upper part of the ST7 addressing space so the reset and interrupt vectors are located in Sector 0 (F000hFFFFh). Table 3. Sectors available in Flash devices Flash Size (bytes) Available Sectors 4K Sector 0 4.2 Main Features ■ ■ ■ ■ Three Flash programming modes: – Insertion in a programming tool. In this mode, all sectors including option bytes can be programmed or erased. – ICP (In-Circuit Programming). In this mode, all sectors including option bytes can be programmed or erased without removing the device from the application board. – IAP (In-Application Programming) In this mode, all sectors except Sector 0, can be programmed or erased without removing the device from the application board and while the application is running. ICT (In-Circuit Testing) for downloading and executing user application test patterns in RAM Read-out protection Register Access Security System (RASS) to prevent accidental programming or erasing 4.3 Structure The Flash memory is organised in sectors and can be used for both code and data storage. 8K Sectors 0,1 > 8K Sectors 0,1, 2 4.3.1 Read-out Protection Read-out protection, when selected, provides a protection against Program Memory content extraction and against write access to Flash memory. Even if no protection can be considered as totally unbreakable, the feature provides a very high level of protection for a general purpose microcontroller. In flash devices, this protection is removed by reprogramming the option. In this case, the entire program memory is first automatically erased. Read-out protection selection depends on the device type: – In Flash devices it is enabled and removed through the FMP_R bit in the option byte. – In ROM devices it is enabled by mask option specified in the Option List. Figure 6. Memory Map and Sector Address 4K 8K 10K 16K 24K 32K 48K 60K 1000h FLASH MEMORY SIZE 3FFFh 7FFFh 9FFFh SECTOR 2 BFFFh D7FFh DFFFh EFFFh FFFFh 2 Kbytes 8 Kbytes 16 Kbytes 24 Kbytes 40 Kbytes 52 Kbytes 4 Kbytes 4 Kbytes SECTOR 1 SECTOR 0 17/167 1 ST72324B FLASH PROGRAM MEMORY (Cont’d) – – – – ICCCLK: ICC output serial clock pin ICCDATA: ICC input/output serial data pin ICCSEL/VPP: programming voltage OSC1(or OSCIN): main clock input for external source (optional) – VDD: application board power supply (optional, see Figure 7, Note 3) 4.4 ICC Interface ICC needs a minimum of 4 and up to 6 pins to be connected to the programming tool (see Figure 7). These pins are: – RESET: device reset – VSS: device power supply ground Figure 7. Typical ICC Interface PROGRAMMING TOOL ICC CONNECTOR Mandatory for 8/16K Flash devices (See Note 4) ICC Cable APPLICATION BOARD ICC CONNECTOR HE10 CONNECTOR TYPE (See Note 3) 9 7 5 3 1 10 8 6 4 2 APPLICATION RESET SOURCE See Note 2 10kΩ Notes: 1. If the ICCCLK or ICCDATA pins are only used as outputs in the application, no signal isolation is necessary. As soon as the Programming Tool is plugged to the board, even if an ICC session is not in progress, the ICCCLK and ICCDATA pins are not available for the application. If they are used as inputs by the application, isolation such as a serial resistor has to implemented in case another device forces the signal. Refer to the Programming Tool documentation for recommended resistor values. 2. During the ICC session, the programming tool must control the RESET pin. This can lead to conflicts between the programming tool and the application reset circuit if it drives more than 5mA at high level (push pull output or pull-up resistor<1K). A schottky diode can be used to isolate the application RESET circuit in this case. When using a classical RC network with R>1K or a reset management IC with open drain output and pull-up resistor>1K, no additional components are needed. In all cases the user must ensure that no external 18/167 1 ICCDATA ICCCLK ST7 RESET See Note 1 ICCSEL/VPP OSC1 CL1 OSC2 VDD CL2 VSS APPLICATION POWER SUPPLY APPLICATION I/O reset is generated by the application during the ICC session. 3. The use of Pin 7 of the ICC connector depends on the Programming Tool architecture. This pin must be connected when using most ST Programming Tools (it is used to monitor the application power supply). Please refer to the Programming Tool manual. 4. Pin 9 has to be connected to the OSC1 or OSCIN pin of the ST7 when the clock is not available in the application or if the selected clock option is not programmed in the option byte. ST7 devices with multi-oscillator capability need to have OSC2 grounded in this case. Caution: External clock ICC entry mode is mandatory in ST72F324B 8K/16K Flash devices. In this case pin 9 must be connected to the OSC1 or OSCIN pin of the ST7 and OSC2 must be grounded. 32K Flash devices may used External Clock or Application Clock ICC entry mode. ST72324B FLASH PROGRAM MEMORY (Cont’d) 4.5 ICP (In-Circuit Programming) To perform ICP the microcontroller must be switched to ICC (In-Circuit Communication) mode by an external controller or programming tool. Depending on the ICP code downloaded in RAM, Flash memory programming can be fully customized (number of bytes to program, program locations, or selection serial communication interface for downloading). When using an STMicroelectronics or third-party programming tool that supports ICP and the specific microcontroller device, the user needs only to implement the ICP hardware interface on the application board (see Figure 7). For more details on the pin locations, refer to the device pinout description. 4.6 IAP (In-Application Programming) This mode uses a BootLoader program previously stored in Sector 0 by the user (in ICP mode or by plugging the device in a programming tool). This mode is fully controlled by user software. This allows it to be adapted to the user application, (user-defined strategy for entering programming mode, choice of communications protocol used to fetch the data to be stored, etc.). For example, it is possible to download code from the SPI, SCI, USB or CAN interface and program it in the Flash. IAP mode can be used to program any of the Flash sectors except Sector 0, which is write/erase protected to allow recovery in case errors occur during the programming operation. 4.7 Related Documentation For details on Flash programming and ICC protocol, refer to the ST7 Flash Programming Reference Manual and to the ST7 ICC Protocol Reference Manual. 4.7.1 Register Description FLASH CONTROL/STATUS REGISTER (FCSR) Read/Write Reset Value: 0000 0000 (00h) 7 0 0 0 0 0 0 0 0 0 This register is reserved for use by Programming Tool software. It controls the Flash programming and erasing operations. Table 4. Flash Control/Status Register Address and Reset Value Address (Hex.) Register Label 0029h FCSR Reset Value 7 6 5 4 3 2 1 0 0 0 0 0 0 0 0 0 19/167 1 ST72324B 5 CENTRAL PROCESSING UNIT 5.1 INTRODUCTION 5.3 CPU REGISTERS This CPU has a full 8-bit architecture and contains six internal registers allowing efficient 8-bit data manipulation. The 6 CPU registers shown in Figure 8 are not present in the memory mapping and are accessed by specific instructions. Accumulator (A) The Accumulator is an 8-bit general purpose register used to hold operands and the results of the arithmetic and logic calculations and to manipulate data. Index Registers (X and Y) These 8-bit registers are used to create effective addresses or as temporary storage areas for data manipulation. (The Cross-Assembler generates a precede instruction (PRE) to indicate that the following instruction refers to the Y register.) The Y register is not affected by the interrupt automatic procedures. Program Counter (PC) The program counter is a 16-bit register containing the address of the next instruction to be executed by the CPU. It is made of two 8-bit registers PCL (Program Counter Low which is the LSB) and PCH (Program Counter High which is the MSB). 5.2 MAIN FEATURES ■ ■ ■ ■ ■ ■ ■ ■ Enable executing 63 basic instructions Fast 8-bit by 8-bit multiply 17 main addressing modes (with indirect addressing mode) Two 8-bit index registers 16-bit stack pointer Low power HALT and WAIT modes Priority maskable hardware interrupts Non-maskable software/hardware interrupts Figure 8. CPU Registers 7 0 ACCUMULATOR RESET VALUE = XXh 7 0 X INDEX REGISTER RESET VALUE = XXh 7 0 Y INDEX REGISTER RESET VALUE = XXh 15 PCH 8 7 PCL 0 PROGRAM COUNTER RESET VALUE = RESET VECTOR @ FFFEh-FFFFh 7 0 1 1 I1 H I0 N Z C CONDITION CODE REGISTER RESET VALUE = 1 1 1 X 1 X X X 15 8 7 0 STACK POINTER RESET VALUE = STACK HIGHER ADDRESS X = Undefined Value 20/167 1 ST72324B CENTRAL PROCESSING UNIT (Cont’d) Condition Code Register (CC) Read/Write Reset Value: 111x1xxx Bit 1 = Z Zero. 7 1 0 1 I1 H I0 N Z C The 8-bit Condition Code register contains the interrupt masks and four flags representative of the result of the instruction just executed. This register can also be handled by the PUSH and POP instructions. These bits can be individually tested and/or controlled by specific instructions. Arithmetic Management Bits Bit 4 = H Half carry. This bit is set by hardware when a carry occurs between bits 3 and 4 of the ALU during an ADD or ADC instructions. It is reset by hardware during the same instructions. 0: No half carry has occurred. 1: A half carry has occurred. This bit is tested using the JRH or JRNH instruction. The H bit is useful in BCD arithmetic subroutines. Bit 2 = N Negative. This bit is set and cleared by hardware. It is representative of the result sign of the last arithmetic, logical or data manipulation. It’s a copy of the result 7th bit. 0: The result of the last operation is positive or null. 1: The result of the last operation is negative (i.e. the most significant bit is a logic 1). This bit is accessed by the JRMI and JRPL instructions. This bit is set and cleared by hardware. This bit indicates that the result of the last arithmetic, logical or data manipulation is zero. 0: The result of the last operation is different from zero. 1: The result of the last operation is zero. This bit is accessed by the JREQ and JRNE test instructions. Bit 0 = C Carry/borrow. This bit is set and cleared by hardware and software. It indicates an overflow or an underflow has occurred during the last arithmetic operation. 0: No overflow or underflow has occurred. 1: An overflow or underflow has occurred. This bit is driven by the SCF and RCF instructions and tested by the JRC and JRNC instructions. It is also affected by the “bit test and branch”, shift and rotate instructions. Interrupt Management Bits Bit 5,3 = I1, I0 Interrupt The combination of the I1 and I0 bits gives the current interrupt software priority. Interrupt Software Priority Level 0 (main) Level 1 Level 2 Level 3 (= interrupt disable) I1 1 0 0 1 I0 0 1 0 1 These two bits are set/cleared by hardware when entering in interrupt. The loaded value is given by the corresponding bits in the interrupt software priority registers (IxSPR). They can be also set/ cleared by software with the RIM, SIM, IRET, HALT, WFI and PUSH/POP instructions. See the interrupt management chapter for more details. 21/167 1 ST72324B CENTRAL PROCESSING UNIT (Cont’d) Stack Pointer (SP) Read/Write Reset Value: 01 FFh 15 0 8 0 0 0 0 0 0 7 SP7 1 0 SP6 SP5 SP4 SP3 SP2 SP1 SP0 The Stack Pointer is a 16-bit register which is always pointing to the next free location in the stack. It is then decremented after data has been pushed onto the stack and incremented before data is popped from the stack (see Figure 9). Since the stack is 256 bytes deep, the 8 most significant bits are forced by hardware. Following an MCU Reset, or after a Reset Stack Pointer instruction (RSP), the Stack Pointer contains its reset value (the SP7 to SP0 bits are set) which is the stack higher address. The least significant byte of the Stack Pointer (called S) can be directly accessed by a LD instruction. Note: When the lower limit is exceeded, the Stack Pointer wraps around to the stack upper limit, without indicating the stack overflow. The previously stored information is then overwritten and therefore lost. The stack also wraps in case of an underflow. The stack is used to save the return address during a subroutine call and the CPU context during an interrupt. The user may also directly manipulate the stack by means of the PUSH and POP instructions. In the case of an interrupt, the PCL is stored at the first location pointed to by the SP. Then the other registers are stored in the next locations as shown in Figure 9. – When an interrupt is received, the SP is decremented and the context is pushed on the stack. – On return from interrupt, the SP is incremented and the context is popped from the stack. A subroutine call occupies two locations and an interrupt five locations in the stack area. Figure 9. Stack Manipulation Example CALL Subroutine PUSH Y Interrupt Event POP Y RET or RSP IRET @ 0100h SP SP CC A 1 CC A X X X PCH PCH PCL PCL PCL PCH PCH PCH PCH PCH PCL PCL PCL PCL PCL Stack Higher Address = 01FFh Stack Lower Address = 0100h 22/167 SP PCH SP @ 01FFh Y CC A SP SP ST72324B 6 SUPPLY, RESET AND CLOCK MANAGEMENT The device includes a range of utility features for securing the application in critical situations (for example in case of a power brown-out), and reducing the number of external components. An overview is shown in Figure 11. For more details, refer to dedicated parametric section. Main features Optional PLL for multiplying the frequency by 2 (not to be used with internal RC oscillator in order to respect the max. operating frequency) ■ Reset Sequence Manager (RSM) ■ Multi-Oscillator Clock Management (MO) – 5 Crystal/Ceramic resonator oscillators – 1 Internal RC oscillator ■ System Integrity Management (SI) – Main supply Low voltage detection (LVD) – Auxiliary Voltage detector (AVD) with interrupt capability for monitoring the main supply ■ 6.1 PHASE LOCKED LOOP If the clock frequency input to the PLL is in the range 2 to 4 MHz, the PLL can be used to multiply the frequency by two to obtain an fOSC2 of 4 to 8 MHz. The PLL is enabled by option byte. If the PLL is disabled, then fOSC2 = fOSC/2. Caution: The PLL is not recommended for applications where timing accuracy is required. Caution: The PLL must not be used with the internal RC oscillator. Figure 10. PLL Block Diagram PLL x 2 0 /2 1 fOSC fOSC2 PLL OPTION BIT Figure 11. Clock, Reset and Supply Block Diagram OSC2 MULTI- OSC1 fOSC2 fOSC OSCILLATOR (MO) PLL (option) MAIN CLOCK fCPU CONTROLLER WITH REALTIME CLOCK (MCC/RTC) SYSTEM INTEGRITY MANAGEMENT RESET SEQUENCE RESET MANAGER (RSM) WATCHDOG AVD Interrupt Request SICSR AVD AVD LVD 0 IE F RF TIMER (WDG) 0 0 0 WDG RF LOW VOLTAGE VSS DETECTOR VDD (LVD) AUXILIARY VOLTAGE DETECTOR (AVD) 23/167 1 ST72324B 6.2 MULTI-OSCILLATOR (MO) 24/167 1 Table 5. ST7 Clock Sources External Clock Hardware Configuration Crystal/Ceramic Resonators External Clock Source In this external clock mode, a clock signal (square, sinus or triangle) with ~50% duty cycle has to drive the OSC1 pin while the OSC2 pin is tied to ground. Crystal/Ceramic Oscillators This family of oscillators has the advantage of producing a very accurate rate on the main clock of the ST7. The selection within a list of 4 oscillators with different frequency ranges has to be done by option byte in order to reduce consumption (refer to Section 14.1 on page 151 for more details on the frequency ranges). In this mode of the multioscillator, the resonator and the load capacitors have to be placed as close as possible to the oscillator pins in order to minimize output distortion and start-up stabilization time. The loading capacitance values must be adjusted according to the selected oscillator. These oscillators are not stopped during the RESET phase to avoid losing time in the oscillator start-up phase. Internal RC Oscillator This oscillator allows a low cost solution for the main clock of the ST7 using only an internal resistor and capacitor. Internal RC oscillator mode has the drawback of a lower frequency accuracy and should not be used in applications that require accurate timing. In this mode, the two oscillator pins have to be tied to ground. In order not to exceed the the max. operating frequency, the internal RC oscillator must not be used with the PLL. Internal RC Oscillator The main clock of the ST7 can be generated by three different source types coming from the multioscillator block: ■ an external source ■ 4 crystal or ceramic resonator oscillators ■ an internal high frequency RC oscillator Each oscillator is optimized for a given frequency range in terms of consumption and is selectable through the option byte. The associated hardware configurations are shown in Table 5. Refer to the electrical characteristics section for more details. Caution: The OSC1 and/or OSC2 pins must not be left unconnected. For the purposes of Failure Mode and Effect Analysis, it should be noted that if the OSC1 and/or OSC2 pins are left unconnected, the ST7 main oscillator may start and, in this configuration, could generate an fOSC clock frequency in excess of the allowed maximum (>16MHz.), putting the ST7 in an unsafe/undefined state. The product behaviour must therefore be considered undefined when the OSC pins are left unconnected. ST7 OSC1 OSC2 EXTERNAL SOURCE ST7 OSC1 CL1 OSC2 LOAD CAPACITORS ST7 OSC1 OSC2 CL2 ST72324B 6.3 RESET SEQUENCE MANAGER (RSM) 6.3.1 Introduction The reset sequence manager includes three RESET sources as shown in Figure 13: ■ External RESET source pulse ■ Internal LVD RESET (Low Voltage Detection) ■ Internal WATCHDOG RESET These sources act on the RESET pin and it is always kept low during the delay phase. The RESET service routine vector is fixed at addresses FFFEh-FFFFh in the ST7 memory map. The basic RESET sequence consists of 3 phases as shown in Figure 12: ■ Active Phase depending on the RESET source ■ 256 or 4096 CPU clock cycle delay (selected by option byte) ■ RESET vector fetch The 256 or 4096 CPU clock cycle delay allows the oscillator to stabilise and ensures that recovery has taken place from the Reset state. The shorter or longer clock cycle delay should be selected by option byte to correspond to the stabilization time of the external oscillator used in the application. The RESET vector fetch phase duration is 2 clock cycles. Figure 12. RESET Sequence Phases RESET Active Phase INTERNAL RESET 256 or 4096 CLOCK CYCLES FETCH VECTOR 6.3.2 Asynchronous External RESET pin The RESET pin is both an input and an open-drain output with integrated RON weak pull-up resistor. This pull-up has no fixed value but varies in accordance with the input voltage. It can be pulled low by external circuitry to reset the device. See Electrical Characteristic section for more details. A RESET signal originating from an external source must have a duration of at least th(RSTL)in in order to be recognized (see Figure 14). This detection is asynchronous and therefore the MCU can enter reset state even in HALT mode. Figure 13. Reset Block Diagram VDD RON RESET INTERNAL RESET Filter PULSE GENERATOR WATCHDOG RESET LVD RESET 25/167 1 ST72324B RESET SEQUENCE MANAGER (Cont’d) The RESET pin is an asynchronous signal which plays a major role in EMS performance. In a noisy environment, it is recommended to follow the guidelines mentioned in the electrical characteristics section. 6.3.3 External Power-On RESET If the LVD is disabled by option byte, to start up the microcontroller correctly, the user must ensure by means of an external reset circuit that the reset signal is held low until VDD is over the minimum level specified for the selected fOSC frequency. A proper reset signal for a slow rising VDD supply can generally be provided by an external RC network connected to the RESET pin. 6.3.4 Internal Low Voltage Detector (LVD) RESET Two different RESET sequences caused by the internal LVD circuitry can be distinguished: ■ Power-On RESET ■ Voltage Drop RESET The device RESET pin acts as an output that is pulled low when VDD<VIT+ (rising edge) or VDD<VIT- (falling edge) as shown in Figure 14. The LVD filters spikes on VDD larger than tg(VDD) to avoid parasitic resets. 6.3.5 Internal Watchdog RESET The RESET sequence generated by a internal Watchdog counter overflow is shown in Figure 14. Starting from the Watchdog counter underflow, the device RESET pin acts as an output that is pulled low during at least tw(RSTL)out. Figure 14. RESET Sequences VDD VIT+(LVD) VIT-(LVD) LVD RESET RUN EXTERNAL RESET RUN ACTIVE PHASE ACTIVE PHASE WATCHDOG RESET RUN ACTIVE PHASE RUN tw(RSTL)out th(RSTL)in EXTERNAL RESET SOURCE RESET PIN WATCHDOG RESET WATCHDOG UNDERFLOW INTERNAL RESET (256 or 4096 TCPU) VECTOR FETCH 26/167 1 ST72324B 6.4 SYSTEM INTEGRITY MANAGEMENT (SI) The System Integrity Management block contains the Low Voltage Detector (LVD) and Auxiliary Voltage Detector (AVD) functions. It is managed by the SICSR register. 6.4.1 Low Voltage Detector (LVD) The Low Voltage Detector function (LVD) generates a static reset when the VDD supply voltage is below a VIT- reference value. This means that it secures the power-up as well as the power-down keeping the ST7 in reset. The VIT- reference value for a voltage drop is lower than the VIT+ reference value for power-on in order to avoid a parasitic reset when the MCU starts running and sinks current on the supply (hysteresis). The LVD Reset circuitry generates a reset when VDD is below: – VIT+ when VDD is rising – VIT- when VDD is falling The LVD function is illustrated in Figure 15. The voltage threshold can be configured by option byte to be low, medium or high. – under full software control – in static safe reset In these conditions, secure operation is always ensured for the application without the need for external reset hardware. During a Low Voltage Detector Reset, the RESET pin is held low, thus permitting the MCU to reset other devices. Notes: The LVD allows the device to be used without any external RESET circuitry. If the medium or low thresholds are selected, the detection may occur outside the specified operating voltage range. Below 3.8V, device operation is not guaranteed. The LVD is an optional function which can be selected by option byte. It is recommended to make sure that the VDD supply voltage rises monotonously when the device is exiting from Reset, to ensure the application functions properly. Provided the minimum VDD value (guaranteed for the oscillator frequency) is above VIT-, the MCU can only be in two modes: Figure 15. Low Voltage Detector vs Reset VDD Vhys VIT+ VIT- RESET 27/167 1 ST72324B SYSTEM INTEGRITY MANAGEMENT (Cont’d) 6.4.2 Auxiliary Voltage Detector (AVD) The Voltage Detector function (AVD) is based on an analog comparison between a VIT-(AVD) and VIT+(AVD) reference value and the VDD main supply. The VIT- reference value for falling voltage is lower than the VIT+ reference value for rising voltage in order to avoid parasitic detection (hysteresis). The output of the AVD comparator is directly readable by the application software through a real time status bit (AVDF) in the SICSR register. This bit is read only. Caution: The AVD function is active only if the LVD is enabled through the option byte (see Section 14.1 on page 151). 6.4.2.1 Monitoring the VDD Main Supply The AVD voltage threshold value is relative to the selected LVD threshold configured by option byte (see If the AVD interrupt is enabled, an interrupt is generated when the voltage crosses the VIT+(AVD) or VIT-(AVD) threshold (AVDF bit toggles). In the case of a drop in voltage, the AVD interrupt acts as an early warning, allowing software to shut down safely before the LVD resets the microcontroller. See Figure 16. The interrupt on the rising edge is used to inform the application that the VDD warning state is over. If the voltage rise time trv is less than 256 or 4096 CPU cycles (depending on the reset delay selected by option byte), no AVD interrupt will be generated when VIT+(AVD) is reached. If trv is greater than 256 or 4096 cycles then: – If the AVD interrupt is enabled before the VIT+(AVD) threshold is reached, then 2 AVD interrupts will be received: the first when the AVDIE bit is set, and the second when the threshold is reached. – If the AVD interrupt is enabled after the VIT+(AVD) threshold is reached then only one AVD interrupt will occur. Figure 16. Using the AVD to Monitor VDD VDD Early Warning Interrupt (Power has dropped, MCU not not yet in reset) Vhyst VIT+(AVD) VIT-(AVD) VIT+(LVD) VIT-(LVD) AVDF bit trv VOLTAGE RISE TIME 0 1 RESET VALUE 1 0 AVD INTERRUPT REQUEST IF AVDIE bit = 1 INTERRUPT PROCESS LVD RESET 28/167 1 INTERRUPT PROCESS ST72324B SYSTEM INTEGRITY MANAGEMENT (Cont’d) 6.4.3 Low Power Modes Mode WAIT HALT Description No effect on SI. AVD interrupt causes the device to exit from Wait mode. The CRSR register is frozen. 6.4.3.1 Interrupts The AVD interrupt event generates an interrupt if the AVDIE bit is set and the interrupt mask in the CC register is reset (RIM instruction). Interrupt Event AVD event Enable Event Control Flag Bit Exit from Wait Exit from Halt AVDF Yes No AVDIE 29/167 1 ST72324B SYSTEM INTEGRITY MANAGEMENT (Cont’d) 6.4.4 Register Description SYSTEM INTEGRITY (SI) CONTROL/STATUS REGISTER (SICSR) Read/Write Bits 3:1 = Reserved, must be kept cleared. Reset Value: 000x 000x (00h) Bit 0 = WDGRF Watchdog reset flag 7 0 This bit indicates that the last Reset was generated by the Watchdog peripheral. It is set by hardAVD AVD LVD WDG 0 0 0 0 ware (watchdog reset) and cleared by software F RF RF IE (writing zero) or an LVD Reset (to ensure a stable cleared state of the WDGRF flag when CPU starts). Bit 7 = Reserved, must be kept cleared. Combined with the LVDRF flag information, the flag description is given by the following table. Bit 6 = AVDIE Voltage Detector interrupt enable RESET Sources LVDRF WDGRF This bit is set and cleared by software. It enables an interrupt to be generated when the AVDF flag External RESET pin 0 0 changes (toggles). The pending interrupt informaWatchdog 0 1 tion is automatically cleared when software enters LVD 1 X the AVD interrupt routine. 0: AVD interrupt disabled 1: AVD interrupt enabled Application notes The LVDRF flag is not cleared when another REBit 5 = AVDF Voltage Detector flag SET type occurs (external or watchdog), the This read-only bit is set and cleared by hardware. LVDRF flag remains set to keep trace of the origiIf the AVDIE bit is set, an interrupt request is gennal failure. erated when the AVDF bit changes value. Refer to In this case, a watchdog reset can be detected by Figure 16 and to Section 6.4.2.1 for additional desoftware while an external reset can not. tails. CAUTION: When the LVD is not activated with the 0: VDD over VIT+(AVD) threshold associated option byte, the WDGRF flag can not 1: VDD under VIT-(AVD) threshold be used in the application. Bit 4 = LVDRF LVD reset flag This bit indicates that the last Reset was generated by the LVD block. It is set by hardware (LVD reset) and cleared by software (writing zero). See WDGRF flag description for more details. When the LVD is disabled by OPTION BYTE, the LVDRF bit value is undefined. 30/167 1 ST72324B 7 INTERRUPTS 7.1 INTRODUCTION The ST7 enhanced interrupt management provides the following features: ■ Hardware interrupts ■ Software interrupt (TRAP) ■ Nested or concurrent interrupt management with flexible interrupt priority and level management: – Up to 4 software programmable nesting levels – Up to 16 interrupt vectors fixed by hardware – 2 non maskable events: RESET, TRAP This interrupt management is based on: – Bit 5 and bit 3 of the CPU CC register (I1:0), – Interrupt software priority registers (ISPRx), – Fixed interrupt vector addresses located at the high addresses of the memory map (FFE0h to FFFFh) sorted by hardware priority order. This enhanced interrupt controller guarantees full upward compatibility with the standard (not nested) ST7 interrupt controller. When an interrupt request has to be serviced: – Normal processing is suspended at the end of the current instruction execution. – The PC, X, A and CC registers are saved onto the stack. – I1 and I0 bits of CC register are set according to the corresponding values in the ISPRx registers of the serviced interrupt vector. – The PC is then loaded with the interrupt vector of the interrupt to service and the first instruction of the interrupt service routine is fetched (refer to “Interrupt Mapping” table for vector addresses). The interrupt service routine should end with the IRET instruction which causes the contents of the saved registers to be recovered from the stack. Note: As a consequence of the IRET instruction, the I1 and I0 bits will be restored from the stack and the program in the previous level will resume. Table 6. Interrupt Software Priority Levels Interrupt software priority Level 0 (main) Level 1 Level 2 Level 3 (= interrupt disable) 7.2 MASKING AND PROCESSING FLOW The interrupt masking is managed by the I1 and I0 bits of the CC register and the ISPRx registers which give the interrupt software priority level of each interrupt vector (see Table 6). The processing flow is shown in Figure 17 Level Low I1 1 0 0 1 High I0 0 1 0 1 Figure 17. Interrupt Processing Flowchart N FETCH NEXT INSTRUCTION Y “IRET” N RESTORE PC, X, A, CC FROM STACK EXECUTE INSTRUCTION Y TRAP Interrupt has the same or a lower software priority than current one THE INTERRUPT STAYS PENDING Y N I1:0 Interrupt has a higher software priority than current one PENDING INTERRUPT RESET STACK PC, X, A, CC LOAD I1:0 FROM INTERRUPT SW REG. LOAD PC FROM INTERRUPT VECTOR 31/167 1 ST72324B INTERRUPTS (Cont’d) Servicing Pending Interrupts As several interrupts can be pending at the same time, the interrupt to be taken into account is determined by the following two-step process: – the highest software priority interrupt is serviced, – if several interrupts have the same software priority then the interrupt with the highest hardware priority is serviced first. Figure 18 describes this decision process. Figure 18. Priority Decision Process PENDING INTERRUPTS Same SOFTWARE PRIORITY Different HIGHEST SOFTWARE PRIORITY SERVICED HIGHEST HARDWARE PRIORITY SERVICED When an interrupt request is not serviced immediately, it is latched and then processed when its software priority combined with the hardware priority becomes the highest one. Note 1: The hardware priority is exclusive while the software one is not. This allows the previous process to succeed with only one interrupt. Note 2: RESET and TRAP can be considered as having the highest software priority in the decision process. Different Interrupt Vector Sources Two interrupt source types are managed by the ST7 interrupt controller: the non-maskable type (RESET,TRAP) and the maskable type (external or from internal peripherals). Non-Maskable Sources These sources are processed regardless of the state of the I1 and I0 bits of the CC register (see Figure 17). After stacking the PC, X, A and CC registers (except for RESET), the corresponding 32/167 1 vector is loaded in the PC register and the I1 and I0 bits of the CC are set to disable interrupts (level 3). These sources allow the processor to exit HALT mode. ■ TRAP (Non Maskable Software Interrupt) This software interrupt is serviced when the TRAP instruction is executed. It will be serviced according to the flowchart in Figure 17. ■ RESET The RESET source has the highest priority in the ST7. This means that the first current routine has the highest software priority (level 3) and the highest hardware priority. See the RESET chapter for more details. Maskable Sources Maskable interrupt vector sources can be serviced if the corresponding interrupt is enabled and if its own interrupt software priority (in ISPRx registers) is higher than the one currently being serviced (I1 and I0 in CC register). If any of these two conditions is false, the interrupt is latched and thus remains pending. ■ External Interrupts External interrupts allow the processor to exit from HALT low power mode. External interrupt sensitivity is software selectable through the External Interrupt Control register (EICR). External interrupt triggered on edge will be latched and the interrupt request automatically cleared upon entering the interrupt service routine. If several input pins of a group connected to the same interrupt line are selected simultaneously, these will be logically ORed. ■ Peripheral Interrupts Usually the peripheral interrupts cause the MCU to exit from HALT mode except those mentioned in the “Interrupt Mapping” table. A peripheral interrupt occurs when a specific flag is set in the peripheral status registers and if the corresponding enable bit is set in the peripheral control register. The general sequence for clearing an interrupt is based on an access to the status register followed by a read or write to an associated register. Note: The clearing sequence resets the internal latch. A pending interrupt (i.e. waiting for being serviced) will therefore be lost if the clear sequence is executed. ST72324B INTERRUPTS (Cont’d) 7.3 INTERRUPTS AND LOW POWER MODES 7.4 CONCURRENT & NESTED MANAGEMENT All interrupts allow the processor to exit the WAIT low power mode. On the contrary, only external and other specified interrupts allow the processor to exit from the HALT modes (see column “Exit from HALT” in “Interrupt Mapping” table). When several pending interrupts are present while exiting HALT mode, the first one serviced can only be an interrupt with exit from HALT mode capability and it is selected through the same decision process shown in Figure 18. Note: If an interrupt, that is not able to Exit from HALT mode, is pending with the highest priority when exiting HALT mode, this interrupt is serviced after the first one serviced. The following Figure 19 and Figure 20 show two different interrupt management modes. The first is called concurrent mode and does not allow an interrupt to be interrupted, unlike the nested mode in Figure 20. The interrupt hardware priority is given in this order from the lowest to the highest: MAIN, IT4, IT3, IT2, IT1, IT0. The software priority is given for each interrupt. Warning: A stack overflow may occur without notifying the software of the failure. IT0 TRAP IT3 IT4 IT1 SOFTWARE PRIORITY LEVEL TRAP IT0 IT1 IT1 IT2 IT3 RIM IT4 MAIN MAIN 11 / 10 I1 I0 3 1 1 3 1 1 3 1 1 3 1 1 3 1 1 3 1 1 USED STACK = 10 BYTES HARDWARE PRIORITY IT2 Figure 19. Concurrent Interrupt Management 3/0 10 IT0 TRAP IT3 IT4 IT1 SOFTWARE PRIORITY LEVEL TRAP IT0 IT1 IT1 IT2 IT2 IT3 RIM IT4 MAIN 11 / 10 IT4 MAIN I1 I0 3 1 1 3 1 1 2 0 0 1 0 1 3 1 1 3 1 1 USED STACK = 20 BYTES HARDWARE PRIORITY IT2 Figure 20. Nested Interrupt Management 3/0 10 33/167 1 ST72324B INTERRUPTS (Cont’d) 7.5 INTERRUPT REGISTER DESCRIPTION CPU CC REGISTER INTERRUPT BITS Read/Write Reset Value: 111x 1010 (xAh) 7 1 0 1 I1 H I0 N Z Level Low High I1 1 0 0 1 7 C Bit 5, 3 = I1, I0 Software Interrupt Priority These two bits indicate the current interrupt software priority. Interrupt Software Priority Level 0 (main) Level 1 Level 2 Level 3 (= interrupt disable*) INTERRUPT SOFTWARE PRIORITY REGISTERS (ISPRX) Read/Write (bit 7:4 of ISPR3 are read only) Reset Value: 1111 1111 (FFh) I0 0 1 0 1 These two bits are set/cleared by hardware when entering in interrupt. The loaded value is given by the corresponding bits in the interrupt software priority registers (ISPRx). They can be also set/cleared by software with the RIM, SIM, HALT, WFI, IRET and PUSH/POP instructions (see “Interrupt Dedicated Instruction Set” table). *Note: TRAP and RESET events can interrupt a level 3 program. 0 ISPR0 I1_3 I0_3 I1_2 I0_2 I1_1 I0_1 I1_0 I0_0 ISPR1 I1_7 I0_7 I1_6 I0_6 I1_5 I0_5 I1_4 I0_4 ISPR2 I1_11 I0_11 I1_10 I0_10 I1_9 I0_9 I1_8 I0_8 ISPR3 1 1 1 1 I1_13 I0_13 I1_12 I0_12 These four registers contain the interrupt software priority of each interrupt vector. – Each interrupt vector (except RESET and TRAP) has corresponding bits in these registers where its own software priority is stored. This correspondance is shown in the following table. Vector address ISPRx bits FFFBh-FFFAh FFF9h-FFF8h ... FFE1h-FFE0h I1_0 and I0_0 bits* I1_1 and I0_1 bits ... I1_13 and I0_13 bits – Each I1_x and I0_x bit value in the ISPRx registers has the same meaning as the I1 and I0 bits in the CC register. – Level 0 can not be written (I1_x=1, I0_x=0). In this case, the previously stored value is kept. (example: previous=CFh, write=64h, result=44h) The RESET, and TRAP vectors have no software priorities. When one is serviced, the I1 and I0 bits of the CC register are both set. Caution: If the I1_x and I0_x bits are modified while the interrupt x is executed the following behaviour has to be considered: If the interrupt x is still pending (new interrupt or flag not cleared) and the new software priority is higher than the previous one, the interrupt x is re-entered. Otherwise, the software priority stays unchanged up to the next interrupt request (after the IRET of the interrupt x). 34/167 1 ST72324B INTERRUPTS (Cont’d) Table 7. Dedicated Interrupt Instruction Set Instruction HALT New Description Function/Example Entering Halt mode I1 H 1 I0 N Z C 0 IRET Interrupt routine return Pop CC, A, X, PC JRM Jump if I1:0=11 (level 3) I1:0=11 ? I1 H I0 N Z C JRNM Jump if I1:0<>11 I1:0<>11 ? POP CC Pop CC from the Stack RIM Enable interrupt (level 0 set) Mem => CC I1 H I0 N Z C Load 10 in I1:0 of CC 1 SIM Disable interrupt (level 3 set) Load 11 in I1:0 of CC 1 1 TRAP Software trap Software NMI 1 1 WFI Wait for interrupt 1 0 0 Note: During the execution of an interrupt routine, the HALT, POPCC, RIM, SIM and WFI instructions change the current software priority up to the next IRET instruction or one of the previously mentioned instructions. 35/167 1 ST72324B INTERRUPTS (Cont’d) Table 8. Interrupt Mapping N° Source Block RESET TRAP Register Label Description Reset N/A Software interrupt 0 Exit from Priority HALT/ Order ACTIVE HALT yes FFFEh-FFFFh no FFFCh-FFFDh Not used 1 MCC/RTC 2 ei0 3 ei1 External interrupt port F2..0 4 ei2 External interrupt port B3..0 5 ei3 External interrupt port B7..4 7 SPI SPI peripheral interrupts 8 TIMER A 9 TIMER B Address Vector FFFAh-FFFBh Main clock controller time base interrupt MCCSR External interrupt port A3..0 Higher Priority yes FFF8h-FFF9h yes FFF6h-FFF7h yes FFF4h-FFF5h yes FFF2h-FFF3h yes FFF0h-FFF1h SPICSR yes FFECh-FFEDh TIMER A peripheral interrupts TASR no FFEAh-FFEBh TIMER B peripheral interrupts TBSR no FFE8h-FFE9h no FFE6h-FFE7h no FFE4h-FFE5h 6 N/A Not used FFEEh-FFEFh 10 SCI SCI Peripheral interrupts SCISR 11 AVD Auxiliary Voltage detector interrupt SICSR Lower Priority 7.6 EXTERNAL INTERRUPTS 7.6.1 I/O Port Interrupt Sensitivity The external interrupt sensitivity is controlled by the IPA, IPB and ISxx bits of the EICR register (Figure 21). This control allows to have up to 4 fully independent external interrupt source sensitivities. Each external interrupt source can be generated on four (or five) different events on the pin: ■ Falling edge ■ Rising edge ■ Falling and rising edge 36/167 1 Falling edge and low level ■ Rising edge and high level (only for ei0 and ei2) To guarantee correct functionality, the sensitivity bits in the EICR register can be modified only when the I1 and I0 bits of the CC register are both set to 1 (level 3). This means that interrupts must be disabled before changing sensitivity. The pending interrupts are cleared by writing a different value in the ISx[1:0], IPA or IPB bits of the EICR. ■ ST72324B Figure 21. External Interrupt Control bits PORT A3 INTERRUPT PAOR.3 PADDR.3 EICR IS20 IS21 ei0 INTERRUPT SOURCE SENSITIVITY PA3 CONTROL IPA BIT PORT F [2:0] INTERRUPTS EICR IS20 PFOR.2 PFDDR.2 IS21 SENSITIVITY PF2 CONTROL PORT B [3:0] INTERRUPTS PBOR.3 PBDDR.3 IS10 IS11 SENSITIVITY CONTROL IPB BIT PBOR.4 PBDDR.4 PB4 ei1 INTERRUPT SOURCE EICR PB3 PORT B4 INTERRUPT PF2 PF1 PF0 PB3 PB2 PB1 PB0 ei2 INTERRUPT SOURCE EICR IS10 IS11 SENSITIVITY ei3 INTERRUPT SOURCE CONTROL 37/167 1 ST72324B INTERRUPTS (Cont’d) 7.7 EXTERNAL INTERRUPT CONTROL REGISTER (EICR) Read/Write Reset Value: 0000 0000 (00h) Bit 4:3 = IS2[1:0] ei0 and ei1 sensitivity The interrupt sensitivity, defined using the IS2[1:0] bits, is applied to the following external interrupts: 7 IS11 0 IS10 IPB IS21 IS20 IPA 0 0 - ei0 (port A3..0) Bit 7:6 = IS1[1:0] ei2 and ei3 sensitivity The interrupt sensitivity, defined using the IS1[1:0] bits, is applied to the following external interrupts: - ei2 (port B3..0) External Interrupt Sensitivity External Interrupt Sensitivity IS21 IS20 0 Falling edge & low level Rising edge & high level IPB bit =0 IPB bit =1 0 1 Rising edge only Falling edge only Falling edge & low level Rising edge & high level 1 0 Falling edge only Rising edge only 1 1 0 0 0 1 Rising edge only Falling edge only 1 0 Falling edge only Rising edge only 1 1 Rising and falling edge Rising and falling edge - ei1 (port F2..0) IS21 IS20 - ei3 (port B4) 0 0 External Interrupt Sensitivity External Interrupt Sensitivity Falling edge & low level 0 1 Rising edge only 0 0 Falling edge & low level 1 0 Falling edge only 0 1 Rising edge only 1 1 Rising and falling edge 1 0 Falling edge only 1 1 Rising and falling edge These 2 bits can be written only when I1 and I0 of the CC register are both set to 1 (level 3). Bit 5 = IPB Interrupt polarity for port B This bit is used to invert the sensitivity of the port B [3:0] external interrupts. It can be set and cleared by software only when I1 and I0 of the CC register are both set to 1 (level 3). 0: No sensitivity inversion 1: Sensitivity inversion 38/167 1 IPA bit =1 0 IS11 IS10 IS11 IS10 IPA bit =0 These 2 bits can be written only when I1 and I0 of the CC register are both set to 1 (level 3). Bit 2 = IPA Interrupt polarity for port A This bit is used to invert the sensitivity of the port A [3:0] external interrupts. It can be set and cleared by software only when I1 and I0 of the CC register are both set to 1 (level 3). 0: No sensitivity inversion 1: Sensitivity inversion Bits 1:0 = Reserved, must always be kept cleared. ST72324B INTERRUPTS (Cont’d) Table 9. Nested Interrupts Register Map and Reset Values Address (Hex.) Register Label 7 0024h ISPR0 Reset Value I1_3 1 6 5 I0_3 1 I1_2 1 ei1 4 ei0 2 I0_7 1 I1_6 1 I1_11 1 I0_11 1 I1_10 1 I0_10 1 MCC + SI I1_1 I0_1 1 1 ei3 I1_5 I0_5 1 1 TIMER B I1_9 I0_9 1 1 1 IS11 0 1 IS10 0 1 IPB 0 1 IS21 0 I1_13 1 IS20 0 I0_2 1 SPI 0025h ISPR1 Reset Value I1_7 1 0026h ISPR2 Reset Value 0027h ISPR3 Reset Value EICR Reset Value AVD 0028h 3 I0_6 1 SCI I0_13 1 IPA 0 1 0 1 1 ei2 I1_4 I0_4 1 1 TIMER A I1_8 I0_8 1 1 I1_12 1 I0_12 1 0 0 39/167 1 ST72324B 8 POWER SAVING MODES 8.1 INTRODUCTION 8.2 SLOW MODE To give a large measure of flexibility to the application in terms of power consumption, four main power saving modes are implemented in the ST7 (see Figure 22): SLOW, WAIT (SLOW WAIT), ACTIVE HALT and HALT. After a RESET the normal operating mode is selected by default (RUN mode). This mode drives the device (CPU and embedded peripherals) by means of a master clock which is based on the main oscillator frequency divided or multiplied by 2 (fOSC2). From RUN mode, the different power saving modes may be selected by setting the relevant register bits or by calling the specific ST7 software instruction whose action depends on the oscillator status. This mode has two targets: – To reduce power consumption by decreasing the internal clock in the device, – To adapt the internal clock frequency (fCPU) to the available supply voltage. SLOW mode is controlled by three bits in the MCCSR register: the SMS bit which enables or disables Slow mode and two CPx bits which select the internal slow frequency (fCPU). In this mode, the master clock frequency (fOSC2) can be divided by 2, 4, 8 or 16. The CPU and peripherals are clocked at this lower frequency (fCPU). Note: SLOW-WAIT mode is activated when entering the WAIT mode while the device is already in SLOW mode. Figure 22. Power Saving Mode Transitions Figure 23. SLOW Mode Clock Transitions High fOSC2/2 fOSC2/4 fOSC2 MCCSR SLOW WAIT CP1:0 00 01 SMS SLOW WAIT NEW SLOW FREQUENCY REQUEST ACTIVE HALT HALT Low POWER CONSUMPTION 40/167 1 fOSC2 fCPU RUN NORMAL RUN MODE REQUEST ST72324B POWER SAVING MODES (Cont’d) 8.3 WAIT MODE WAIT mode places the MCU in a low power consumption mode by stopping the CPU. This power saving mode is selected by calling the ‘WFI’ instruction. All peripherals remain active. During WAIT mode, the I[1:0] bits of the CC register are forced to ‘10’, to enable all interrupts. All other registers and memory remain unchanged. The MCU remains in WAIT mode until an interrupt or RESET occurs, whereupon the Program Counter branches to the starting address of the interrupt or Reset service routine. The MCU will remain in WAIT mode until a Reset or an Interrupt occurs, causing it to wake up. Refer to Figure 24. Figure 24. WAIT Mode Flow-chart WFI INSTRUCTION OSCILLATOR PERIPHERALS CPU I[1:0] BITS ON ON OFF 10 N RESET Y N INTERRUPT Y OSCILLATOR PERIPHERALS CPU I[1:0] BITS ON OFF ON 10 256 OR 4096 CPU CLOCK CYCLE DELAY OSCILLATOR ON PERIPHERALS ON CPU ON I[1:0] BITS XX 1) FETCH RESET VECTOR OR SERVICE INTERRUPT Note: 1. Before servicing an interrupt, the CC register is pushed on the stack. The I[1:0] bits of the CC register are set to the current software priority level of the interrupt routine and recovered when the CC register is popped. 41/167 1 ST72324B POWER SAVING MODES (Cont’d) 8.4 ACTIVE-HALT AND HALT MODES ACTIVE-HALT and HALT modes are the two lowest power consumption modes of the MCU. They are both entered by executing the ‘HALT’ instruction. The decision to enter either in ACTIVE-HALT or HALT mode is given by the MCC/RTC interrupt enable flag (OIE bit in MCCSR register). MCCSR OIE bit Power Saving Mode entered when HALT instruction is executed 0 HALT mode 1 ACTIVE-HALT mode pending on option byte). Otherwise, the ST7 enters HALT mode for the remaining tDELAY period. Figure 25. ACTIVE-HALT Timing Overview RUN ACTIVE 256 OR 4096 CPU HALT CYCLE DELAY 1) HALT INSTRUCTION [MCCSR.OIE=1] RESET OR INTERRUPT RUN FETCH VECTOR Figure 26. ACTIVE-HALT Mode Flow-chart 8.4.1 ACTIVE-HALT MODE ACTIVE-HALT mode is the lowest power consumption mode of the MCU with a real time clock available. It is entered by executing the ‘HALT’ instruction when the OIE bit of the Main Clock Controller Status register (MCCSR) is set (see Section 10.2 on page 56 for more details on the MCCSR register). The MCU can exit ACTIVE-HALT mode on reception of either an MCC/RTC interrupt, a specific interrupt (see Table 8, “Interrupt Mapping,” on page 36) or a RESET. When exiting ACTIVEHALT mode by means of an interrupt, no 256 or 4096 CPU cycle delay occurs. The CPU resumes operation by servicing the interrupt or by fetching the reset vector which woke it up (see Figure 26). When entering ACTIVE-HALT mode, the I[1:0] bits in the CC register are forced to ‘10b’ to enable interrupts. Therefore, if an interrupt is pending, the MCU wakes up immediately. In ACTIVE-HALT mode, only the main oscillator and its associated counter (MCC/RTC) are running to keep a wake-up time base. All other peripherals are not clocked except those which get their clock supply from another clock generator (such as external or auxiliary oscillator). The safeguard against staying locked in ACTIVEHALT mode is provided by the oscillator interrupt. Note: As soon as the interrupt capability of one of the oscillators is selected (MCCSR.OIE bit set), entering ACTIVE-HALT mode while the Watchdog is active does not generate a RESET. This means that the device cannot spend more than a defined delay in this power saving mode. CAUTION: When exiting ACTIVE-HALT mode following an interrupt, OIE bit of MCCSR register must not be cleared before tDELAY after the interrupt occurs (tDELAY = 256 or 4096 tCPU delay de- 42/167 1 HALT INSTRUCTION (MCCSR.OIE=1) OSCILLATOR PERIPHERALS 2) CPU I[1:0] BITS N N INTERRUPT 3) Y ON OFF OFF 10 RESET Y OSCILLATOR PERIPHERALS CPU I[1:0] BITS ON OFF ON XX 4) 256 OR 4096 CPU CLOCK CYCLE DELAY OSCILLATOR PERIPHERALS CPU I[1:0] BITS ON ON ON XX 4) FETCH RESET VECTOR OR SERVICE INTERRUPT Notes: 1. This delay occurs only if the MCU exits ACTIVEHALT mode by means of a RESET. 2. Peripheral clocked with an external clock source can still be active. 3. Only the MCC/RTC interrupt and some specific interrupts can exit the MCU from ACTIVE-HALT mode (such as external interrupt). Refer to Table 8, “Interrupt Mapping,” on page 36 for more details. 4. Before servicing an interrupt, the CC register is pushed on the stack. The I[1:0] bits of the CC register are set to the current software priority level of the interrupt routine and restored when the CC register is popped. ST72324B POWER SAVING MODES (Cont’d) 8.4.2 HALT MODE The HALT mode is the lowest power consumption mode of the MCU. It is entered by executing the ‘HALT’ instruction when the OIE bit of the Main Clock Controller Status register (MCCSR) is cleared (see Section 10.2 on page 56 for more details on the MCCSR register). The MCU can exit HALT mode on reception of either a specific interrupt (see Table 8, “Interrupt Mapping,” on page 36) or a RESET. When exiting HALT mode by means of a RESET or an interrupt, the oscillator is immediately turned on and the 256 or 4096 CPU cycle delay is used to stabilize the oscillator. After the start up delay, the CPU resumes operation by servicing the interrupt or by fetching the reset vector which woke it up (see Figure 28). When entering HALT mode, the I[1:0] bits in the CC register are forced to ‘10b’to enable interrupts. Therefore, if an interrupt is pending, the MCU wakes up immediately. In HALT mode, the main oscillator is turned off causing all internal processing to be stopped, including the operation of the on-chip peripherals. All peripherals are not clocked except the ones which get their clock supply from another clock generator (such as an external or auxiliary oscillator). The compatibility of Watchdog operation with HALT mode is configured by the “WDGHALT” option bit of the option byte. The HALT instruction when executed while the Watchdog system is enabled, can generate a Watchdog RESET (see Section 14.1 on page 151) for more details. Figure 28. HALT Mode Flow-chart HALT INSTRUCTION (MCCSR.OIE=0) ENABLE WDGHALT 1) WATCHDOG 0 DISABLE 1 WATCHDOG RESET OSCILLATOR OFF PERIPHERALS 2) OFF CPU OFF I[1:0] BITS 10 N RESET N Y INTERRUPT 3) Y OSCILLATOR ON PERIPHERALS OFF CPU ON I[1:0] BITS XX 4) 256 OR 4096 CPU CLOCK CYCLE DELAY OSCILLATOR ON PERIPHERALS ON CPU ON I[1:0] BITS XX 4) Figure 27. HALT Timing Overview RUN HALT HALT INSTRUCTION [MCCSR.OIE=0] 256 OR 4096 CPU CYCLE DELAY RUN RESET OR INTERRUPT FETCH VECTOR FETCH RESET VECTOR OR SERVICE INTERRUPT Notes: 1. WDGHALT is an option bit. See option byte section for more details. 2. Peripheral clocked with an external clock source can still be active. 3. Only some specific interrupts can exit the MCU from HALT mode (such as external interrupt). Refer to Table 8, “Interrupt Mapping,” on page 36 for more details. 4. Before servicing an interrupt, the CC register is pushed on the stack. The I[1:0] bits of the CC register are set to the current software priority level of the interrupt routine and recovered when the CC register is popped. 43/167 1 ST72324B POWER SAVING MODES (Cont’d) 8.4.2.1 Halt Mode Recommendations – Make sure that an external event is available to wake up the microcontroller from Halt mode. – When using an external interrupt to wake up the microcontroller, reinitialize the corresponding I/O as “Input Pull-up with Interrupt” before executing the HALT instruction. The main reason for this is that the I/O may be wrongly configured due to external interference or by an unforeseen logical condition. – For the same reason, reinitialize the level sensitiveness of each external interrupt as a precautionary measure. 44/167 1 – The opcode for the HALT instruction is 0x8E. To avoid an unexpected HALT instruction due to a program counter failure, it is advised to clear all occurrences of the data value 0x8E from memory. For example, avoid defining a constant in ROM with the value 0x8E. – As the HALT instruction clears the interrupt mask in the CC register to allow interrupts, the user may choose to clear all pending interrupt bits before executing the HALT instruction. This avoids entering other peripheral interrupt routines after executing the external interrupt routine corresponding to the wake-up event (reset or external interrupt). ST72324B 9 I/O PORTS 9.1 INTRODUCTION The I/O ports offer different functional modes: – transfer of data through digital inputs and outputs and for specific pins: – external interrupt generation – alternate signal input/output for the on-chip peripherals. An I/O port contains up to 8 pins. Each pin can be programmed independently as digital input (with or without interrupt generation) or digital output. 9.2 FUNCTIONAL DESCRIPTION Each port has 2 main registers: – Data Register (DR) – Data Direction Register (DDR) and one optional register: – Option Register (OR) Each I/O pin may be programmed using the corresponding register bits in the DDR and OR registers: bit X corresponding to pin X of the port. The same correspondence is used for the DR register. The following description takes into account the OR register, (for specific ports which do not provide this register refer to the I/O Port Implementation section). The generic I/O block diagram is shown in Figure 29 9.2.1 Input Modes The input configuration is selected by clearing the corresponding DDR register bit. In this case, reading the DR register returns the digital value applied to the external I/O pin. Different input modes can be selected by software through the OR register. Notes: 1. Writing the DR register modifies the latch value but does not affect the pin status. 2. When switching from input to output mode, the DR register has to be written first to drive the correct level on the pin as soon as the port is configured as an output. 3. Do not use read/modify/write instructions (BSET or BRES) to modify the DR register External interrupt function When an I/O is configured as Input with Interrupt, an event on this I/O can generate an external interrupt request to the CPU. Each pin can independently generate an interrupt request. The interrupt sensitivity is independently programmable using the sensitivity bits in the EICR register. Each external interrupt vector is linked to a dedicated group of I/O port pins (see pinout description and interrupt section). If several input pins are selected simultaneously as interrupt sources, these are first detected according to the sensitivity bits in the EICR register and then logically ORed. The external interrupts are hardware interrupts, which means that the request latch (not accessible directly by the application) is automatically cleared when the corresponding interrupt vector is fetched. To clear an unwanted pending interrupt by software, the sensitivity bits in the EICR register must be modified. 9.2.2 Output Modes The output configuration is selected by setting the corresponding DDR register bit. In this case, writing the DR register applies this digital value to the I/O pin through the latch. Then reading the DR register returns the previously stored value. Two different output modes can be selected by software through the OR register: Output push-pull and open-drain. DR register value and output pin status: DR 0 1 Push-pull VSS VDD Open-drain Vss Floating 9.2.3 Alternate Functions When an on-chip peripheral is configured to use a pin, the alternate function is automatically selected. This alternate function takes priority over the standard I/O programming. When the signal is coming from an on-chip peripheral, the I/O pin is automatically configured in output mode (push-pull or open drain according to the peripheral). When the signal is going to an on-chip peripheral, the I/O pin must be configured in input mode. In this case, the pin state is also digitally readable by addressing the DR register. Note: Input pull-up configuration can cause unexpected value at the input of the alternate peripheral input. When an on-chip peripheral use a pin as input and output, this pin has to be configured in input floating mode. 45/167 1 ST72324B I/O PORTS (Cont’d) Figure 29. I/O Port General Block Diagram ALTERNATE OUTPUT REGISTER ACCESS 1 P-BUFFER (see table below) VDD 0 ALTERNATE ENABLE PULL-UP (see table below) DR VDD DDR PULL-UP CONDITION DATA BUS OR PAD If implemented OR SEL N-BUFFER DIODES (see table below) DDR SEL DR SEL ANALOG INPUT CMOS SCHMITT TRIGGER 1 0 ALTERNATE INPUT EXTERNAL INTERRUPT SOURCE (eix) Table 10. I/O Port Mode Options Configuration Mode Input Output Floating with/without Interrupt Pull-up with/without Interrupt Push-pull Open Drain (logic level) True Open Drain Legend: NI - not implemented Off - implemented not activated On - implemented and activated 46/167 1 Pull-Up P-Buffer Off On Off Off NI On Off NI Diodes to VDD On to VSS On NI (see note) Note: The diode to VDD is not implemented in the true open drain pads. A local protection between the pad and VSS is implemented to protect the device against positive stress. ST72324B I/O PORTS (Cont’d) Table 11. I/O Port Configurations Hardware Configuration NOT IMPLEMENTED IN TRUE OPEN DRAIN I/O PORTS DR REGISTER ACCESS VDD RPU PULL-UP CONDITION DR REGISTER PAD W DATA BUS INPUT 1) R ALTERNATE INPUT EXTERNAL INTERRUPT SOURCE (eix) INTERRUPT CONDITION PUSH-PULL OUTPUT 2) OPEN-DRAIN OUTPUT 2) ANALOG INPUT NOT IMPLEMENTED IN TRUE OPEN DRAIN I/O PORTS DR REGISTER ACCESS VDD RPU DR REGISTER PAD ALTERNATE ENABLE NOT IMPLEMENTED IN TRUE OPEN DRAIN I/O PORTS R/W DATA BUS ALTERNATE OUTPUT DR REGISTER ACCESS VDD RPU PAD DR REGISTER ALTERNATE ENABLE R/W DATA BUS ALTERNATE OUTPUT Notes: 1. When the I/O port is in input configuration and the associated alternate function is enabled as an output, reading the DR register will read the alternate function output status. 2. When the I/O port is in output configuration and the associated alternate function is enabled as an input, the alternate function reads the pin status given by the DR register content. 47/167 1 ST72324B I/O PORTS (Cont’d) CAUTION: The alternate function must not be activated as long as the pin is configured as input with interrupt, in order to avoid generating spurious interrupts. Analog alternate function When the pin is used as an ADC input, the I/O must be configured as floating input. The analog multiplexer (controlled by the ADC registers) switches the analog voltage present on the selected pin to the common analog rail which is connected to the ADC input. It is recommended not to change the voltage level or loading on any port pin while conversion is in progress. Furthermore it is recommended not to have clocking pins located close to a selected analog pin. WARNING: The analog input voltage level must be within the limits stated in the absolute maximum ratings. Figure 30. Interrupt I/O Port State Transitions 01 00 10 11 INPUT floating/pull-up interrupt INPUT floating (reset state) OUTPUT open-drain OUTPUT push-pull XX = DDR, OR 9.4 LOW POWER MODES Mode WAIT HALT Description No effect on I/O ports. External interrupts cause the device to exit from WAIT mode. No effect on I/O ports. External interrupts cause the device to exit from HALT mode. 9.5 INTERRUPTS 9.3 I/O PORT IMPLEMENTATION The hardware implementation on each I/O port depends on the settings in the DDR and OR registers and specific feature of the I/O port such as ADC Input or true open drain. Switching these I/O ports from one state to another should be done in a sequence that prevents unwanted side effects. Recommended safe transitions are illustrated in Figure 30 Other transitions are potentially risky and should be avoided, since they are likely to present unwanted side-effects such as spurious interrupt generation. 48/167 1 The external interrupt event generates an interrupt if the corresponding configuration is selected with DDR and OR registers and the interrupt mask in the CC register is not active (RIM instruction). Interrupt Event External interrupt on selected external event Enable Event Control Flag Bit - DDRx ORx Exit from Wait Exit from Halt Yes Yes ST72324B I/O PORTS (Cont’d) 9.5.1 I/O Port Implementation The I/O port register configurations are summarised as follows. PA3, PB3 (without pull-up) MODE floating input floating interrupt input open drain output push-pull output Standard Ports PA5:4, PC7:0, PD5:0, PE1:0, PF7:6, 4 MODE floating input pull-up input open drain output push-pull output DDR 0 0 1 1 OR 0 1 0 1 MODE floating input open drain (high sink ports) DDR 0 0 1 1 OR 0 1 0 1 True Open Drain Ports PA7:6 Interrupt Ports PB4, PB2:0, PF2:0 (with pull-up) MODE floating input pull-up interrupt input open drain output push-pull output DDR 0 0 1 1 DDR 0 1 OR 0 1 0 1 Table 12. Port Configuration Port Port A Port B Port C Port D Port E Port F Pin name PA7:6 PA5:4 PA3 PB3 PB4, PB2:0 PC7:0 PD5:0 PE1:0 PF7:6, 4 PF2:0 Input Output OR = 0 OR = 1 floating floating floating floating floating floating floating floating floating floating pull-up floating interrupt floating interrupt pull-up interrupt pull-up pull-up pull-up pull-up pull-up interrupt OR = 0 OR = 1 true open-drain open drain push-pull open drain push-pull open drain push-pull open drain push-pull open drain push-pull open drain push-pull open drain push-pull open drain push-pull open drain push-pull 49/167 1 ST72324B I/O PORTS (Cont’d) Table 13. I/O Port Register Map and Reset Values Address (Hex.) Register Label Reset Value of all I/O port registers 0000h PADR 0001h PADDR 0002h PAOR 0003h PBDR 0004h PBDDR 0005h PBOR 0006h PCDR 0007h PCDDR 0008h PCOR 0009h PDDR 000Ah PDDDR 000Bh PDOR 000Ch PEDR 000Dh PEDDR 000Eh PEOR 000Fh PFDR 0010h PFDDR 0011h PFOR 50/167 1 7 6 5 4 3 2 1 0 0 0 0 0 0 0 0 0 MSB LSB MSB LSB MSB LSB MSB LSB MSB LSB MSB LSB ST72324B 10 ON-CHIP PERIPHERALS 10.1 WATCHDOG TIMER (WDG) 10.1.1 Introduction The Watchdog timer is used to detect the occurrence of a software fault, usually generated by external interference or by unforeseen logical conditions, which causes the application program to abandon its normal sequence. The Watchdog circuit generates an MCU reset on expiry of a programmed time period, unless the program refreshes the counter’s contents before the T6 bit becomes cleared. 10.1.2 Main Features ■ Programmable free-running downcounter ■ Programmable reset ■ Reset (if watchdog activated) when the T6 bit reaches zero ■ Optional reset on HALT instruction (configurable by option byte) ■ Hardware Watchdog selectable by option byte 10.1.3 Functional Description The counter value stored in the Watchdog Control register (WDGCR bits T[6:0]), is decremented every 16384 fOSC2 cycles (approx.), and the length of the timeout period can be programmed by the user in 64 increments. If the watchdog is activated (the WDGA bit is set) and when the 7-bit timer (bits T[6:0]) rolls over from 40h to 3Fh (T6 becomes cleared), it initiates a reset cycle pulling low the reset pin for typically 500ns. The application program must write in the WDGCR register at regular intervals during normal operation to prevent an MCU reset. This downcounter is free-running: it counts down even if the watchdog is disabled. The value to be stored in the WDGCR register must be between FFh and C0h: – The WDGA bit is set (watchdog enabled) – The T6 bit is set to prevent generating an immediate reset – The T[5:0] bits contain the number of increments which represents the time delay before the watchdog produces a reset (see Figure 32. Approximate Timeout Duration). The timing varies between a minimum and a maximum value due to the unknown status of the prescaler when writing to the WDGCR register (see Figure 33). Following a reset, the watchdog is disabled. Once activated it cannot be disabled, except by a reset. The T6 bit can be used to generate a software reset (the WDGA bit is set and the T6 bit is cleared). If the watchdog is activated, the HALT instruction will generate a Reset. Figure 31. Watchdog Block Diagram RESET fOSC2 MCC/RTC WATCHDOG CONTROL REGISTER (WDGCR) DIV 64 WDGA T6 T5 T4 T3 T2 T1 T0 6-BIT DOWNCOUNTER (CNT) 12-BIT MCC RTC COUNTER MSB 11 LSB 6 5 0 TB[1:0] bits (MCCSR Register) WDG PRESCALER DIV 4 51/167 1 ST72324B WATCHDOG TIMER (Cont’d) 10.1.4 How to Program the Watchdog Timeout Figure 32 shows the linear relationship between the 6-bit value to be loaded in the Watchdog Counter (CNT) and the resulting timeout duration in milliseconds. This can be used for a quick calculation without taking the timing variations into account. If more precision is needed, use the formulae in Figure 33. Caution: When writing to the WDGCR register, always write 1 in the T6 bit to avoid generating an immediate reset. Figure 32. Approximate Timeout Duration 3F 38 CNT Value (hex.) 30 28 20 18 10 08 00 1.5 18 34 50 65 82 Watchdog timeout (ms) @ 8 MHz. fOSC2 52/167 1 98 114 128 ST72324B WATCHDOG TIMER (Cont’d) Figure 33. Exact Timeout Duration (tmin and tmax) WHERE: tmin0 = (LSB + 128) x 64 x tOSC2 tmax0 = 16384 x tOSC2 tOSC2 = 125ns if fOSC2=8 MHz CNT = Value of T[5:0] bits in the WDGCR register (6 bits) MSB and LSB are values from the table below depending on the timebase selected by the TB[1:0] bits in the MCCSR register TB1 Bit TB0 Bit (MCCSR Reg.) (MCCSR Reg.) 0 0 0 1 1 0 1 1 Selected MCCSR Timebase MSB LSB 2ms 4ms 10ms 25ms 4 8 20 49 59 53 35 54 To calculate the minimum Watchdog Timeout (tmin): IF CNT < MSB ------------4 THEN t min = t min0 + 16384 × CNT × t osc2 4CNT ELSE t min = t min0 + 16384 × ⎛⎝ CNT – 4CNT ----------------- ⎞ + ( 192 + LSB ) × 64 × ----------------MSB MSB ⎠ × t osc2 To calculate the maximum Watchdog Timeout (tmax): IF CNT ≤ MSB ------------4 THEN t max = t max0 + 16384 × CNT × t osc2 4CNT ELSE t max = t max0 + 16384 × ⎛⎝ CNT – 4CNT ----------------- ⎞ + ( 192 + LSB ) × 64 × ----------------MSB ⎠ MSB × t osc2 Note: In the above formulae, division results must be rounded down to the next integer value. Example: With 2ms timeout selected in MCCSR register Value of T[5:0] Bits in WDGCR Register (Hex.) 00 3F Min. Watchdog Timeout (ms) tmin 1.496 128 Max. Watchdog Timeout (ms) tmax 2.048 128.552 53/167 1 ST72324B WATCHDOG TIMER (Cont’d) 10.1.5 Low Power Modes Mode SLOW WAIT Description No effect on Watchdog. No effect on Watchdog. OIE bit in MCCSR register WDGHALT bit in Option Byte 0 0 0 1 1 x HALT No Watchdog reset is generated. The MCU enters Halt mode. The Watchdog counter is decremented once and then stops counting and is no longer able to generate a watchdog reset until the MCU receives an external interrupt or a reset. If an external interrupt is received, the Watchdog restarts counting after 256 or 4096 CPU clocks. If a reset is generated, the Watchdog is disabled (reset state) unless Hardware Watchdog is selected by option byte. For application recommendations see Section 10.1.7 below. A reset is generated. No reset is generated. The MCU enters Active Halt mode. The Watchdog counter is not decremented. It stop counting. When the MCU receives an oscillator interrupt or external interrupt, the Watchdog restarts counting immediately. When the MCU receives a reset the Watchdog restarts counting after 256 or 4096 CPU clocks. 10.1.6 Hardware Watchdog Option If Hardware Watchdog is selected by option byte, the watchdog is always active and the WDGA bit in the WDGCR is not used. Refer to the Option Byte description. 10.1.7 Using Halt Mode with the WDG (WDGHALT option) The following recommendation applies if Halt mode is used when the watchdog is enabled. – Before executing the HALT instruction, refresh the WDG counter, to avoid an unexpected WDG reset immediately after waking up the microcontroller. 10.1.8 Interrupts None. 54/167 1 10.1.9 Register Description CONTROL REGISTER (WDGCR) Read/Write Reset Value: 0111 1111 (7Fh) 7 WDGA 0 T6 T5 T4 T3 T2 T1 T0 Bit 7 = WDGA Activation bit. This bit is set by software and only cleared by hardware after a reset. When WDGA = 1, the watchdog can generate a reset. 0: Watchdog disabled 1: Watchdog enabled Note: This bit is not used if the hardware watchdog option is enabled by option byte. Bit 6:0 = T[6:0] 7-bit counter (MSB to LSB). These bits contain the value of the watchdog counter. It is decremented every 16384 fOSC2 cycles (approx.). A reset is produced when it rolls over from 40h to 3Fh (T6 becomes cleared). ST72324B Table 14. Watchdog Timer Register Map and Reset Values Address (Hex.) Register Label 7 6 5 4 3 2 1 0 002Ah WDGCR Reset Value WDGA 0 T6 1 T5 1 T4 1 T3 1 T2 1 T1 1 T0 1 55/167 1 ST72324B 10.2 MAIN CLOCK CONTROLLER WITH REAL TIME CLOCK AND BEEPER (MCC/RTC) The Main Clock Controller consists of three different functions: ■ a programmable CPU clock prescaler ■ a clock-out signal to supply external devices ■ a real time clock timer with interrupt capability Each function can be used independently and simultaneously. 10.2.1 Programmable CPU Clock Prescaler The programmable CPU clock prescaler supplies the clock for the ST7 CPU and its internal peripherals. It manages SLOW power saving mode (See Section 8.2 SLOW MODE for more details). The prescaler selects the fCPU main clock frequency and is controlled by three bits in the MCCSR register: CP[1:0] and SMS. 10.2.2 Clock-out Capability The clock-out capability is an alternate function of an I/O port pin that outputs the fCPU clock to drive external devices. It is controlled by the MCO bit in the MCCSR register. CAUTION: When selected, the clock out pin suspends the clock during ACTIVE-HALT mode. 10.2.3 Real Time Clock Timer (RTC) The counter of the real time clock timer allows an interrupt to be generated based on an accurate real time clock. Four different time bases depending directly on fOSC2 are available. The whole functionality is controlled by four bits of the MCCSR register: TB[1:0], OIE and OIF. When the RTC interrupt is enabled (OIE bit set), the ST7 enters ACTIVE-HALT mode when the HALT instruction is executed. See Section 8.4 ACTIVE-HALT AND HALT MODES for more details. 10.2.4 Beeper The beep function is controlled by the MCCBCR register. It can output three selectable frequencies on the BEEP pin (I/O port alternate function). Figure 34. Main Clock Controller (MCC/RTC) Block Diagram BC1 BC0 MCCBCR BEEP BEEP SIGNAL SELECTION MCO 12-BIT MCC RTC COUNTER DIV 64 MCO CP1 CP0 SMS TB1 TB0 OIE MCCSR fOSC2 DIV 2, 4, 8, 16 1 OIF MCC/RTC INTERRUPT 1 0 56/167 TO WATCHDOG TIMER fCPU CPU CLOCK TO CPU AND PERIPHERALS ST72324B MAIN CLOCK CONTROLLER WITH REAL TIME CLOCK (Cont’d) 10.2.5 Low Power Modes Bit 6:5 = CP[1:0] CPU clock prescaler Mode Description These bits select the CPU clock prescaler which is No effect on MCC/RTC peripheral. applied in the different slow modes. Their action is WAIT MCC/RTC interrupt cause the device to exit conditioned by the setting of the SMS bit. These from WAIT mode. two bits are set and cleared by software ACTIVEHALT HALT No effect on MCC/RTC counter (OIE bit is set), the registers are frozen. MCC/RTC interrupt cause the device to exit from ACTIVE-HALT mode. MCC/RTC counter and registers are frozen. MCC/RTC operation resumes when the MCU is woken up by an interrupt with “exit from HALT” capability. 10.2.6 Interrupts The MCC/RTC interrupt event generates an interrupt if the OIE bit of the MCCSR register is set and the interrupt mask in the CC register is not active (RIM instruction). Interrupt Event Time base overflow event Enable Event Control Flag Bit OIF OIE Exit from Wait Exit from Halt Yes No 1) Note: The MCC/RTC interrupt wakes up the MCU from ACTIVE-HALT mode, not from HALT mode. 10.2.7 Register Description MCC CONTROL/STATUS REGISTER (MCCSR) Read/Write Reset Value: 0000 0000 (00h) 7 MCO 0 CP1 CP0 SMS TB1 TB0 OIE fCPU in SLOW mode CP1 CP0 fOSC2 / 2 0 0 fOSC2 / 4 0 1 fOSC2 / 8 1 0 fOSC2 / 16 1 1 Bit 4 = SMS Slow mode select This bit is set and cleared by software. 0: Normal mode. fCPU = fOSC2 1: Slow mode. fCPU is given by CP1, CP0 See Section 8.2 SLOW MODE and Section 10.2 MAIN CLOCK CONTROLLER WITH REAL TIME CLOCK AND BEEPER (MCC/RTC) for more details. Bit 3:2 = TB[1:0] Time base control These bits select the programmable divider time base. They are set and cleared by software. Time Base Counter Prescaler f OSC2 =4MHz fOSC2=8MHz TB1 TB0 16000 4ms 2ms 0 0 32000 8ms 4ms 0 1 80000 20ms 10ms 1 0 200000 50ms 25ms 1 1 A modification of the time base is taken into account at the end of the current period (previously set) to avoid an unwanted time shift. This allows to use this time base as a real time clock. OIF Bit 7 = MCO Main clock out selection This bit enables the MCO alternate function on the PF0 I/O port. It is set and cleared by software. 0: MCO alternate function disabled (I/O pin free for general-purpose I/O) 1: MCO alternate function enabled (fCPU on I/O port) Note: To reduce power consumption, the MCO function is not active in ACTIVE-HALT mode. Bit 1 = OIE Oscillator interrupt enable This bit set and cleared by software. 0: Oscillator interrupt disabled 1: Oscillator interrupt enabled This interrupt can be used to exit from ACTIVEHALT mode. When this bit is set, calling the ST7 software HALT instruction enters the ACTIVE-HALT power saving mode. 57/167 1 ST72324B MAIN CLOCK CONTROLLER WITH REAL TIME CLOCK (Cont’d) MCC BEEP CONTROL REGISTER (MCCBCR) Bit 0 = OIF Oscillator interrupt flag This bit is set by hardware and cleared by software Read/Write reading the MCCSR register. It indicates when set Reset Value: 0000 0000 (00h) that the main oscillator has reached the selected elapsed time (TB1:0). 7 0 0: Timeout not reached 1: Timeout reached 0 0 0 0 0 0 BC1 BC0 CAUTION: The BRES and BSET instructions must not be used on the MCCSR register to avoid Bit 7:2 = Reserved, must be kept cleared. unintentionally clearing the OIF bit. Bit 1:0 = BC[1:0] Beep control These 2 bits select the PF1 pin beep capability. BC1 BC0 Beep mode with fOSC2=8MHz 0 0 Off 0 1 ~2-KHz 1 0 ~1-KHz 1 1 ~500-Hz Output Beep signal ~50% duty cycle The beep output signal is available in ACTIVEHALT mode but has to be disabled to reduce the consumption. Table 15. Main Clock Controller Register Map and Reset Values Address (Hex.) 002Bh 002Ch 002Dh 58/167 1 Register Label SICSR Reset Value MCCSR Reset Value MCCBCR Reset Value 7 6 5 4 3 2 1 0 0 MCO 0 AVDIE 0 CP1 0 AVDF 0 CP0 0 LVDRF x SMS 0 0 TB1 0 0 TB0 0 0 0 0 0 0 0 0 OIE 0 BC1 0 WDGRF x OIF 0 BC0 0 ST72324B 10.3 16-BIT TIMER 10.3.1 Introduction The timer consists of a 16-bit free-running counter driven by a programmable prescaler. It may be used for a variety of purposes, including pulse length measurement of up to two input signals (input capture) or generation of up to two output waveforms (output compare and PWM). Pulse lengths and waveform periods can be modulated from a few microseconds to several milliseconds using the timer prescaler and the CPU clock prescaler. Some ST7 devices have two on-chip 16-bit timers. They are completely independent, and do not share any resources. They are synchronized after a MCU reset as long as the timer clock frequencies are not modified. This description covers one or two 16-bit timers. In ST7 devices with two timers, register names are prefixed with TA (Timer A) or TB (Timer B). 10.3.2 Main Features ■ Programmable prescaler: fCPU divided by 2, 4 or 8. ■ Overflow status flag and maskable interrupt ■ External clock input (must be at least 4 times slower than the CPU clock speed) with the choice of active edge ■ 1 or 2 Output Compare functions each with: – 2 dedicated 16-bit registers – 2 dedicated programmable signals – 2 dedicated status flags – 1 dedicated maskable interrupt ■ 1 or 2 Input Capture functions each with: – 2 dedicated 16-bit registers – 2 dedicated active edge selection signals – 2 dedicated status flags – 1 dedicated maskable interrupt ■ Pulse width modulation mode (PWM) ■ One pulse mode ■ Reduced Power Mode ■ 5 alternate functions on I/O ports (ICAP1, ICAP2, OCMP1, OCMP2, EXTCLK)* When reading an input signal on a non-bonded pin, the value will always be ‘1’. 10.3.3 Functional Description 10.3.3.1 Counter The main block of the Programmable Timer is a 16-bit free running upcounter and its associated 16-bit registers. The 16-bit registers are made up of two 8-bit registers called high & low. Counter Register (CR): – Counter High Register (CHR) is the most significant byte (MS Byte). – Counter Low Register (CLR) is the least significant byte (LS Byte). Alternate Counter Register (ACR) – Alternate Counter High Register (ACHR) is the most significant byte (MS Byte). – Alternate Counter Low Register (ACLR) is the least significant byte (LS Byte). These two read-only 16-bit registers contain the same value but with the difference that reading the ACLR register does not clear the TOF bit (Timer overflow flag), located in the Status register, (SR), (see note at the end of paragraph titled 16-bit read sequence). Writing in the CLR register or ACLR register resets the free running counter to the FFFCh value. Both counters have a reset value of FFFCh (this is the only value which is reloaded in the 16-bit timer). The reset value of both counters is also FFFCh in One Pulse mode and PWM mode. The timer clock depends on the clock control bits of the CR2 register, as illustrated in Table 1. The value in the counter register repeats every 131072, 262144 or 524288 CPU clock cycles depending on the CC[1:0] bits. The timer frequency can be fCPU/2, fCPU/4, fCPU/8 or an external frequency. The Block Diagram is shown in Figure 1. *Note: Some timer pins may not be available (not bonded) in some ST7 devices. Refer to the device pin out description. 59/167 1 ST72324B 16-BIT TIMER (Cont’d) Figure 35. Timer Block Diagram ST7 INTERNAL BUS fCPU MCU-PERIPHERAL INTERFACE 8 low 8 8 8 low 8 high 8 low 8 high EXEDG 8 low high 8 high 8-bit buffer low 8 high 16 1/2 1/4 1/8 OUTPUT COMPARE REGISTER 2 OUTPUT COMPARE REGISTER 1 COUNTER REGISTER ALTERNATE COUNTER REGISTER EXTCLK pin INPUT CAPTURE REGISTER 1 INPUT CAPTURE REGISTER 2 16 16 16 CC[1:0] TIMER INTERNAL BUS 16 16 OVERFLOW DETECT CIRCUIT OUTPUT COMPARE CIRCUIT 6 ICF1 OCF1 TOF ICF2 OCF2 TIMD 0 EDGE DETECT CIRCUIT1 ICAP1 pin EDGE DETECT CIRCUIT2 ICAP2 pin LATCH1 OCMP1 pin LATCH2 OCMP2 pin 0 (Control/Status Register) CSR ICIE OCIE TOIE FOLV2 FOLV1 OLVL2 IEDG1 OLVL1 (Control Register 1) CR1 OC1E OC2E OPM PWM CC1 CC0 IEDG2 EXEDG (Control Register 2) CR2 (See note) TIMER INTERRUPT 60/167 1 Note: If IC, OC and TO interrupt requests have separate vectors then the last OR is not present (See device Interrupt Vector Table) ST72324B 16-BIT TIMER (Cont’d) 16-bit read sequence: (from either the Counter Register or the Alternate Counter Register). Beginning of the sequence At t0 Read MS Byte LS Byte is buffered Other instructions Read At t0 +∆t LS Byte Returns the buffered LS Byte value at t0 Sequence completed The user must read the MS Byte first, then the LS Byte value is buffered automatically. This buffered value remains unchanged until the 16-bit read sequence is completed, even if the user reads the MS Byte several times. After a complete reading sequence, if only the CLR register or ACLR register are read, they return the LS Byte of the count value at the time of the read. Whatever the timer mode used (input capture, output compare, one pulse mode or PWM mode) an overflow occurs when the counter rolls over from FFFFh to 0000h then: – The TOF bit of the SR register is set. – A timer interrupt is generated if: – TOIE bit of the CR1 register is set and – I bit of the CC register is cleared. If one of these conditions is false, the interrupt remains pending to be issued as soon as they are both true. Clearing the overflow interrupt request is done in two steps: 1. Reading the SR register while the TOF bit is set. 2. An access (read or write) to the CLR register. Notes: The TOF bit is not cleared by accesses to ACLR register. The advantage of accessing the ACLR register rather than the CLR register is that it allows simultaneous use of the overflow function and reading the free running counter at random times (for example, to measure elapsed time) without the risk of clearing the TOF bit erroneously. The timer is not affected by WAIT mode. In HALT mode, the counter stops counting until the mode is exited. Counting then resumes from the previous count (MCU awakened by an interrupt) or from the reset count (MCU awakened by a Reset). 10.3.3.2 External Clock The external clock (where available) is selected if CC0=1 and CC1=1 in the CR2 register. The status of the EXEDG bit in the CR2 register determines the type of level transition on the external clock pin EXTCLK that will trigger the free running counter. The counter is synchronized with the falling edge of the internal CPU clock. A minimum of four falling edges of the CPU clock must occur between two consecutive active edges of the external clock; thus the external clock frequency must be less than a quarter of the CPU clock frequency. 61/167 1 ST72324B 16-BIT TIMER (Cont’d) Figure 36. Counter Timing Diagram, internal clock divided by 2 CPU CLOCK INTERNAL RESET TIMER CLOCK FFFD FFFE FFFF 0000 COUNTER REGISTER 0001 0002 0003 TIMER OVERFLOW FLAG (TOF) Figure 37. Counter Timing Diagram, internal clock divided by 4 CPU CLOCK INTERNAL RESET TIMER CLOCK COUNTER REGISTER FFFC FFFD 0000 0001 TIMER OVERFLOW FLAG (TOF) Figure 38. Counter Timing Diagram, internal clock divided by 8 CPU CLOCK INTERNAL RESET TIMER CLOCK COUNTER REGISTER FFFC FFFD 0000 TIMER OVERFLOW FLAG (TOF) Note: The MCU is in reset state when the internal reset signal is high, when it is low the MCU is running. 62/167 1 ST72324B 16-BIT TIMER (Cont’d) 10.3.3.3 Input Capture In this section, the index, i, may be 1 or 2 because there are 2 input capture functions in the 16-bit timer. The two 16-bit input capture registers (IC1R and IC2R) are used to latch the value of the free running counter after a transition is detected on the ICAPi pin (see figure 5). ICiR MS Byte ICiHR LS Byte ICiLR ICiR register is a read-only register. The active transition is software programmable through the IEDGi bit of Control Registers (CRi). Timing resolution is one count of the free running counter: (fCPU/CC[1:0]). Procedure: To use the input capture function select the following in the CR2 register: – Select the timer clock (CC[1:0]) (see Table 1). – Select the edge of the active transition on the ICAP2 pin with the IEDG2 bit (the ICAP2 pin must be configured as floating input or input with pull-up without interrupt if this configuration is available). And select the following in the CR1 register: – Set the ICIE bit to generate an interrupt after an input capture coming from either the ICAP1 pin or the ICAP2 pin – Select the edge of the active transition on the ICAP1 pin with the IEDG1 bit (the ICAP1pin must be configured as floating input or input with pullup without interrupt if this configuration is available). When an input capture occurs: – ICFi bit is set. – The ICiR register contains the value of the free running counter on the active transition on the ICAPi pin (see Figure 6). – A timer interrupt is generated if the ICIE bit is set and the I bit is cleared in the CC register. Otherwise, the interrupt remains pending until both conditions become true. Clearing the Input Capture interrupt request (i.e. clearing the ICFi bit) is done in two steps: 1. Reading the SR register while the ICFi bit is set. 2. An access (read or write) to the ICiLR register. Notes: 1. After reading the ICiHR register, transfer of input capture data is inhibited and ICFi will never be set until the ICiLR register is also read. 2. The ICiR register contains the free running counter value which corresponds to the most recent input capture. 3. The 2 input capture functions can be used together even if the timer also uses the 2 output compare functions. 4. In One pulse Mode and PWM mode only Input Capture 2 can be used. 5. The alternate inputs (ICAP1 & ICAP2) are always directly connected to the timer. So any transitions on these pins activates the input capture function. Moreover if one of the ICAPi pins is configured as an input and the second one as an output, an interrupt can be generated if the user toggles the output pin and if the ICIE bit is set. This can be avoided if the input capture function i is disabled by reading the ICiHR (see note 1). 6. The TOF bit can be used with interrupt generation in order to measure events that go beyond the timer range (FFFFh). 63/167 1 ST72324B 16-BIT TIMER (Cont’d) Figure 39. Input Capture Block Diagram ICAP1 pin ICAP2 pin (Control Register 1) CR1 EDGE DETECT CIRCUIT2 EDGE DETECT CIRCUIT1 ICIE IEDG1 (Status Register) SR IC2R Register IC1R Register ICF1 ICF2 0 16-BIT FREE RUNNING COUNTER CC1 CC0 Figure 40. Input Capture Timing Diagram TIMER CLOCK FF01 FF02 FF03 ICAPi PIN ICAPi FLAG ICAPi REGISTER Note: The rising edge is the active edge. 64/167 1 0 (Control Register 2) CR2 16-BIT COUNTER REGISTER 0 FF03 IEDG2 ST72324B 16-BIT TIMER (Cont’d) 10.3.3.4 Output Compare In this section, the index, i, may be 1 or 2 because there are 2 output compare functions in the 16-bit timer. This function can be used to control an output waveform or indicate when a period of time has elapsed. When a match is found between the Output Compare register and the free running counter, the output compare function: – Assigns pins with a programmable value if the OCiE bit is set – Sets a flag in the status register – Generates an interrupt if enabled Two 16-bit registers Output Compare Register 1 (OC1R) and Output Compare Register 2 (OC2R) contain the value to be compared to the counter register each timer clock cycle. OCiR MS Byte OCiHR LS Byte OCiLR These registers are readable and writable and are not affected by the timer hardware. A reset event changes the OCiR value to 8000h. Timing resolution is one count of the free running counter: (fCPU/CC[1:0]). Procedure: To use the output compare function, select the following in the CR2 register: – Set the OCiE bit if an output is needed then the OCMPi pin is dedicated to the output compare i signal. – Select the timer clock (CC[1:0]) (see Table 1). And select the following in the CR1 register: – Select the OLVLi bit to applied to the OCMPi pins after the match occurs. – Set the OCIE bit to generate an interrupt if it is needed. When a match is found between OCRi register and CR register: – OCFi bit is set. – The OCMPi pin takes OLVLi bit value (OCMPi pin latch is forced low during reset). – A timer interrupt is generated if the OCIE bit is set in the CR1 register and the I bit is cleared in the CC register (CC). The OCiR register value required for a specific timing application can be calculated using the following formula: ∆ OCiR = ∆t * fCPU PRESC Where: ∆t = Output compare period (in seconds) fCPU = CPU clock frequency (in hertz) = Timer prescaler factor (2, 4 or 8 dePRESC pending on CC[1:0] bits, see Table 1) If the timer clock is an external clock, the formula is: ∆ OCiR = ∆t * fEXT Where: ∆t = Output compare period (in seconds) fEXT = External timer clock frequency (in hertz) Clearing the output compare interrupt request (i.e. clearing the OCFi bit) is done by: 1. Reading the SR register while the OCFi bit is set. 2. An access (read or write) to the OCiLR register. The following procedure is recommended to prevent the OCFi bit from being set between the time it is read and the write to the OCiR register: – Write to the OCiHR register (further compares are inhibited). – Read the SR register (first step of the clearance of the OCFi bit, which may be already set). – Write to the OCiLR register (enables the output compare function and clears the OCFi bit). 65/167 1 ST72324B 16-BIT TIMER (Cont’d) Notes: 1. After a processor write cycle to the OCiHR register, the output compare function is inhibited until the OCiLR register is also written. 2. If the OCiE bit is not set, the OCMPi pin is a general I/O port and the OLVLi bit will not appear when a match is found but an interrupt could be generated if the OCIE bit is set. 3. When the timer clock is fCPU/2, OCFi and OCMPi are set while the counter value equals the OCiR register value (see Figure 8). This behaviour is the same in OPM or PWM mode. When the timer clock is fCPU/4, fCPU/8 or in external clock mode, OCFi and OCMPi are set while the counter value equals the OCiR register value plus 1 (see Figure 9). 4. The output compare functions can be used both for generating external events on the OCMPi pins even if the input capture mode is also used. 5. The value in the 16-bit OCiR register and the OLVi bit should be changed after each successful comparison in order to control an output waveform or establish a new elapsed timeout. Forced Compare Output capability When the FOLVi bit is set by software, the OLVLi bit is copied to the OCMPi pin. The OLVi bit has to be toggled in order to toggle the OCMPi pin when it is enabled (OCiE bit=1). The OCFi bit is then not set by hardware, and thus no interrupt request is generated. The FOLVLi bits have no effect in both one pulse mode and PWM mode. Figure 41. Output Compare Block Diagram 16 BIT FREE RUNNING COUNTER OC1E OC2E CC1 CC0 (Control Register 2) CR2 16-bit (Control Register 1) CR1 OUTPUT COMPARE CIRCUIT 16-bit OCIE FOLV2 FOLV1 OLVL2 OLVL1 16-bit Latch 2 OC1R Register OCF1 OCF2 0 0 0 OC2R Register (Status Register) SR 66/167 1 Latch 1 OCMP1 Pin OCMP2 Pin ST72324B 16-BIT TIMER (Cont’d) Figure 42. Output Compare Timing Diagram, fTIMER =fCPU/2 INTERNAL CPU CLOCK TIMER CLOCK COUNTER REGISTER 2ECF 2ED0 2ED1 2ED2 2ED3 2ED4 OUTPUT COMPARE REGISTER i (OCRi) 2ED3 OUTPUT COMPARE FLAG i (OCFi) OCMPi PIN (OLVLi=1) Figure 43. Output Compare Timing Diagram, fTIMER =fCPU/4 INTERNAL CPU CLOCK TIMER CLOCK COUNTER REGISTER OUTPUT COMPARE REGISTER i (OCRi) 2ECF 2ED0 2ED1 2ED2 2ED3 2ED4 2ED3 COMPARE REGISTER i LATCH OUTPUT COMPARE FLAG i (OCFi) OCMPi PIN (OLVLi=1) 67/167 1 ST72324B 16-BIT TIMER (Cont’d) 10.3.3.5 One Pulse Mode One Pulse mode enables the generation of a pulse when an external event occurs. This mode is selected via the OPM bit in the CR2 register. The one pulse mode uses the Input Capture1 function and the Output Compare1 function. Procedure: To use one pulse mode: 1. Load the OC1R register with the value corresponding to the length of the pulse (see the formula in the opposite column). 2. Select the following in the CR1 register: – Using the OLVL1 bit, select the level to be applied to the OCMP1 pin after the pulse. – Using the OLVL2 bit, select the level to be applied to the OCMP1 pin during the pulse. – Select the edge of the active transition on the ICAP1 pin with the IEDG1 bit (the ICAP1 pin must be configured as floating input). 3. Select the following in the CR2 register: – Set the OC1E bit, the OCMP1 pin is then dedicated to the Output Compare 1 function. – Set the OPM bit. – Select the timer clock CC[1:0] (see Table 1). One pulse mode cycle When event occurs on ICAP1 ICR1 = Counter OCMP1 = OLVL2 Counter is reset to FFFCh ICF1 bit is set When Counter = OC1R OCMP1 = OLVL1 Then, on a valid event on the ICAP1 pin, the counter is initialized to FFFCh and OLVL2 bit is loaded on the OCMP1 pin, the ICF1 bit is set and the value FFFDh is loaded in the IC1R register. Because the ICF1 bit is set when an active edge occurs, an interrupt can be generated if the ICIE bit is set. 68/167 1 Clearing the Input Capture interrupt request (i.e. clearing the ICFi bit) is done in two steps: 1. Reading the SR register while the ICFi bit is set. 2. An access (read or write) to the ICiLR register. The OC1R register value required for a specific timing application can be calculated using the following formula: OCiR Value = t * fCPU -5 PRESC Where: t = Pulse period (in seconds) fCPU = CPU clock frequency (in hertz) PRESC = Timer prescaler factor (2, 4 or 8 depending on the CC[1:0] bits, see Table 1) If the timer clock is an external clock the formula is: OCiR = t * fEXT -5 Where: t = Pulse period (in seconds) fEXT = External timer clock frequency (in hertz) When the value of the counter is equal to the value of the contents of the OC1R register, the OLVL1 bit is output on the OCMP1 pin, (See Figure 10). Notes: 1. The OCF1 bit cannot be set by hardware in one pulse mode but the OCF2 bit can generate an Output Compare interrupt. 2. When the Pulse Width Modulation (PWM) and One Pulse Mode (OPM) bits are both set, the PWM mode is the only active one. 3. If OLVL1=OLVL2 a continuous signal will be seen on the OCMP1 pin. 4. The ICAP1 pin can not be used to perform input capture. The ICAP2 pin can be used to perform input capture (ICF2 can be set and IC2R can be loaded) but the user must take care that the counter is reset each time a valid edge occurs on the ICAP1 pin and ICF1 can also generates interrupt if ICIE is set. 5. When one pulse mode is used OC1R is dedicated to this mode. Nevertheless OC2R and OCF2 can be used to indicate a period of time has been elapsed but cannot generate an output waveform because the level OLVL2 is dedicated to the one pulse mode. ST72324B 16-BIT TIMER (Cont’d) Figure 44. One Pulse Mode Timing Example COUNTER 2ED3 01F8 IC1R 01F8 FFFC FFFD FFFE 2ED0 2ED1 2ED2 FFFC FFFD 2ED3 ICAP1 OLVL2 OCMP1 OLVL1 OLVL2 compare1 Note: IEDG1=1, OC1R=2ED0h, OLVL1=0, OLVL2=1 Figure 45. Pulse Width Modulation Mode Timing Example with 2 Output Compare Functions COUNTER 34E2 FFFC FFFD FFFE 2ED0 2ED1 2ED2 OLVL2 OCMP1 compare2 OLVL1 compare1 34E2 FFFC OLVL2 compare2 Note: OC1R=2ED0h, OC2R=34E2, OLVL1=0, OLVL2= 1 Note: On timers with only 1 Output Compare register, a fixed frequency PWM signal can be generated using the output compare and the counter overflow to define the pulse length. 69/167 1 ST72324B 16-BIT TIMER (Cont’d) 10.3.3.6 Pulse Width Modulation Mode Pulse Width Modulation (PWM) mode enables the generation of a signal with a frequency and pulse length determined by the value of the OC1R and OC2R registers. Pulse Width Modulation mode uses the complete Output Compare 1 function plus the OC2R register, and so this functionality can not be used when PWM mode is activated. In PWM mode, double buffering is implemented on the output compare registers. Any new values written in the OC1R and OC2R registers are taken into account only at the end of the PWM period (OC2) to avoid spikes on the PWM output pin (OCMP1). Procedure To use pulse width modulation mode: 1. Load the OC2R register with the value corresponding to the period of the signal using the formula in the opposite column. 2. Load the OC1R register with the value corresponding to the period of the pulse if (OLVL1=0 and OLVL2=1) using the formula in the opposite column. 3. Select the following in the CR1 register: – Using the OLVL1 bit, select the level to be applied to the OCMP1 pin after a successful comparison with the OC1R register. – Using the OLVL2 bit, select the level to be applied to the OCMP1 pin after a successful comparison with the OC2R register. 4. Select the following in the CR2 register: – Set OC1E bit: the OCMP1 pin is then dedicated to the output compare 1 function. – Set the PWM bit. – Select the timer clock (CC[1:0]) (see Table 1). Pulse Width Modulation cycle When Counter = OC1R When Counter = OC2R OCMP1 = OLVL1 OCMP1 = OLVL2 Counter is reset to FFFCh ICF1 bit is set 70/167 1 If OLVL1=1 and OLVL2=0 the length of the positive pulse is the difference between the OC2R and OC1R registers. If OLVL1=OLVL2 a continuous signal will be seen on the OCMP1 pin. The OCiR register value required for a specific timing application can be calculated using the following formula: OCiR Value = t * fCPU -5 PRESC Where: t = Signal or pulse period (in seconds) fCPU = CPU clock frequency (in hertz) PRESC = Timer prescaler factor (2, 4 or 8 depending on CC[1:0] bits, see Table 1) If the timer clock is an external clock the formula is: OCiR = t * fEXT -5 Where: t = Signal or pulse period (in seconds) fEXT = External timer clock frequency (in hertz) The Output Compare 2 event causes the counter to be initialized to FFFCh (See Figure 11) Notes: 1. After a write instruction to the OCiHR register, the output compare function is inhibited until the OCiLR register is also written. 2. The OCF1 and OCF2 bits cannot be set by hardware in PWM mode therefore the Output Compare interrupt is inhibited. 3. The ICF1 bit is set by hardware when the counter reaches the OC2R value and can produce a timer interrupt if the ICIE bit is set and the I bit is cleared. 4. In PWM mode the ICAP1 pin can not be used to perform input capture because it is disconnected to the timer. The ICAP2 pin can be used to perform input capture (ICF2 can be set and IC2R can be loaded) but the user must take care that the counter is reset each period and ICF1 can also generates interrupt if ICIE is set. 5. When the Pulse Width Modulation (PWM) and One Pulse Mode (OPM) bits are both set, the PWM mode is the only active one. ST72324B 16-BIT TIMER (Cont’d) 10.3.4 Low Power Modes Mode WAIT HALT Description No effect on 16-bit Timer. Timer interrupts cause the device to exit from WAIT mode. 16-bit Timer registers are frozen. In HALT mode, the counter stops counting until Halt mode is exited. Counting resumes from the previous count when the MCU is woken up by an interrupt with “exit from HALT mode” capability or from the counter reset value when the MCU is woken up by a RESET. If an input capture event occurs on the ICAPi pin, the input capture detection circuitry is armed. Consequently, when the MCU is woken up by an interrupt with “exit from HALT mode” capability, the ICFi bit is set, and the counter value present when exiting from HALT mode is captured into the ICiR register. 10.3.5 Interrupts Event Flag Interrupt Event Input Capture 1 event/Counter reset in PWM mode Input Capture 2 event Output Compare 1 event (not available in PWM mode) Output Compare 2 event (not available in PWM mode) Timer Overflow event ICF1 ICF2 OCF1 OCF2 TOF Enable Control Bit ICIE OCIE TOIE Exit from Wait Yes Yes Yes Yes Yes Exit from Halt No No No No No Note: The 16-bit Timer interrupt events are connected to the same interrupt vector (see Interrupts chapter). These events generate an interrupt if the corresponding Enable Control Bit is set and the interrupt mask in the CC register is reset (RIM instruction). 10.3.6 Summary of Timer modes MODES Input Capture (1 and/or 2) Output Compare (1 and/or 2) One Pulse Mode PWM Mode Input Capture 1 Yes Yes No No TIMER RESOURCES Input Capture 2 Output Compare 1 Output Compare 2 Yes Yes Yes Yes Yes Yes No Partially 2) Not Recommended1) 3) Not Recommended No No 1) See note 4 in Section 0.1.3.5 One Pulse Mode 2) See note 5 in Section 0.1.3.5 One Pulse Mode 3) See note 4 in Section 0.1.3.6 Pulse Width Modulation Mode 71/167 1 ST72324B 16-BIT TIMER (Cont’d) 10.3.7 Register Description Each Timer is associated with three control and status registers, and with six pairs of data registers (16-bit values) relating to the two input captures, the two output compares, the counter and the alternate counter. CONTROL REGISTER 1 (CR1) Read/Write Reset Value: 0000 0000 (00h) 7 0 Bit 4 = FOLV2 Forced Output Compare 2. This bit is set and cleared by software. 0: No effect on the OCMP2 pin. 1: Forces the OLVL2 bit to be copied to the OCMP2 pin, if the OC2E bit is set and even if there is no successful comparison. Bit 3 = FOLV1 Forced Output Compare 1. This bit is set and cleared by software. 0: No effect on the OCMP1 pin. 1: Forces OLVL1 to be copied to the OCMP1 pin, if the OC1E bit is set and even if there is no successful comparison. ICIE OCIE TOIE FOLV2 FOLV1 OLVL2 IEDG1 OLVL1 Bit 7 = ICIE Input Capture Interrupt Enable. 0: Interrupt is inhibited. 1: A timer interrupt is generated whenever the ICF1 or ICF2 bit of the SR register is set. Bit 6 = OCIE Output Compare Interrupt Enable. 0: Interrupt is inhibited. 1: A timer interrupt is generated whenever the OCF1 or OCF2 bit of the SR register is set. Bit 5 = TOIE Timer Overflow Interrupt Enable. 0: Interrupt is inhibited. 1: A timer interrupt is enabled whenever the TOF bit of the SR register is set. 72/167 1 Bit 2 = OLVL2 Output Level 2. This bit is copied to the OCMP2 pin whenever a successful comparison occurs with the OC2R register and OCxE is set in the CR2 register. This value is copied to the OCMP1 pin in One Pulse Mode and Pulse Width Modulation mode. Bit 1 = IEDG1 Input Edge 1. This bit determines which type of level transition on the ICAP1 pin will trigger the capture. 0: A falling edge triggers the capture. 1: A rising edge triggers the capture. Bit 0 = OLVL1 Output Level 1. The OLVL1 bit is copied to the OCMP1 pin whenever a successful comparison occurs with the OC1R register and the OC1E bit is set in the CR2 register. ST72324B 16-BIT TIMER (Cont’d) CONTROL REGISTER 2 (CR2) Read/Write Reset Value: 0000 0000 (00h) 7 0 OC1E OC2E OPM PWM CC1 CC0 IEDG2 EXEDG Bit 7 = OC1E Output Compare 1 Pin Enable. This bit is used only to output the signal from the timer on the OCMP1 pin (OLV1 in Output Compare mode, both OLV1 and OLV2 in PWM and one-pulse mode). Whatever the value of the OC1E bit, the Output Compare 1 function of the timer remains active. 0: OCMP1 pin alternate function disabled (I/O pin free for general-purpose I/O). 1: OCMP1 pin alternate function enabled. Bit 6 = OC2E Output Compare 2 Pin Enable. This bit is used only to output the signal from the timer on the OCMP2 pin (OLV2 in Output Compare mode). Whatever the value of the OC2E bit, the Output Compare 2 function of the timer remains active. 0: OCMP2 pin alternate function disabled (I/O pin free for general-purpose I/O). 1: OCMP2 pin alternate function enabled. Bit 5 = OPM One Pulse Mode. 0: One Pulse Mode is not active. 1: One Pulse Mode is active, the ICAP1 pin can be used to trigger one pulse on the OCMP1 pin; the active transition is given by the IEDG1 bit. The length of the generated pulse depends on the contents of the OC1R register. Bit 4 = PWM Pulse Width Modulation. 0: PWM mode is not active. 1: PWM mode is active, the OCMP1 pin outputs a programmable cyclic signal; the length of the pulse depends on the value of OC1R register; the period depends on the value of OC2R register. Bit 3, 2 = CC[1:0] Clock Control. The timer clock mode depends on these bits: Table 16. Clock Control Bits Timer Clock fCPU / 4 fCPU / 2 fCPU / 8 External Clock (where available) CC1 0 0 1 CC0 0 1 0 1 1 Note: If the external clock pin is not available, programming the external clock configuration stops the counter. Bit 1 = IEDG2 Input Edge 2. This bit determines which type of level transition on the ICAP2 pin will trigger the capture. 0: A falling edge triggers the capture. 1: A rising edge triggers the capture. Bit 0 = EXEDG External Clock Edge. This bit determines which type of level transition on the external clock pin EXTCLK will trigger the counter register. 0: A falling edge triggers the counter register. 1: A rising edge triggers the counter register. 73/167 1 ST72324B 16-BIT TIMER (Cont’d) CONTROL/STATUS REGISTER (CSR) Read/Write (bits 7:3 read only) Reset Value: xxxx x0xx (xxh) Note: Reading or writing the ACLR register does not clear TOF. 7 ICF1 0 OCF1 TOF ICF2 OCF2 TIMD 0 0 Bit 7 = ICF1 Input Capture Flag 1. 0: No input capture (reset value). 1: An input capture has occurred on the ICAP1 pin or the counter has reached the OC2R value in PWM mode. To clear this bit, first read the SR register, then read or write the low byte of the IC1R (IC1LR) register. Bit 6 = OCF1 Output Compare Flag 1. 0: No match (reset value). 1: The content of the free running counter has matched the content of the OC1R register. To clear this bit, first read the SR register, then read or write the low byte of the OC1R (OC1LR) register. Bit 5 = TOF Timer Overflow Flag. 0: No timer overflow (reset value). 1: The free running counter rolled over from FFFFh to 0000h. To clear this bit, first read the SR register, then read or write the low byte of the CR (CLR) register. 74/167 1 Bit 4 = ICF2 Input Capture Flag 2. 0: No input capture (reset value). 1: An input capture has occurred on the ICAP2 pin. To clear this bit, first read the SR register, then read or write the low byte of the IC2R (IC2LR) register. Bit 3 = OCF2 Output Compare Flag 2. 0: No match (reset value). 1: The content of the free running counter has matched the content of the OC2R register. To clear this bit, first read the SR register, then read or write the low byte of the OC2R (OC2LR) register. Bit 2 = TIMD Timer disable. This bit is set and cleared by software. When set, it freezes the timer prescaler and counter and disabled the output functions (OCMP1 and OCMP2 pins) to reduce power consumption. Access to the timer registers is still available, allowing the timer configuration to be changed, or the counter reset, while it is disabled. 0: Timer enabled 1: Timer prescaler, counter and outputs disabled Bits 1:0 = Reserved, must be kept cleared. ST72324B 16-BIT TIMER (Cont’d) INPUT CAPTURE 1 HIGH REGISTER (IC1HR) Read Only Reset Value: Undefined This is an 8-bit read only register that contains the high part of the counter value (transferred by the input capture 1 event). OUTPUT COMPARE 1 HIGH REGISTER (OC1HR) Read/Write Reset Value: 1000 0000 (80h) This is an 8-bit register that contains the high part of the value to be compared to the CHR register. 7 0 7 0 MSB LSB MSB LSB INPUT CAPTURE 1 LOW REGISTER (IC1LR) Read Only Reset Value: Undefined This is an 8-bit read only register that contains the low part of the counter value (transferred by the input capture 1 event). OUTPUT COMPARE 1 LOW REGISTER (OC1LR) Read/Write Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the low part of the value to be compared to the CLR register. 7 0 7 0 MSB LSB MSB LSB 75/167 1 ST72324B 16-BIT TIMER (Cont’d) OUTPUT COMPARE 2 HIGH REGISTER (OC2HR) Read/Write Reset Value: 1000 0000 (80h) This is an 8-bit register that contains the high part of the value to be compared to the CHR register. ALTERNATE COUNTER HIGH REGISTER (ACHR) Read Only Reset Value: 1111 1111 (FFh) This is an 8-bit register that contains the high part of the counter value. 7 0 7 0 MSB LSB MSB LSB OUTPUT COMPARE 2 LOW REGISTER (OC2LR) Read/Write Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the low part of the value to be compared to the CLR register. 7 0 MSB LSB COUNTER HIGH REGISTER (CHR) Read Only Reset Value: 1111 1111 (FFh) This is an 8-bit register that contains the high part of the counter value. 7 0 MSB LSB COUNTER LOW REGISTER (CLR) Read Only Reset Value: 1111 1100 (FCh) This is an 8-bit register that contains the low part of the counter value. A write to this register resets the counter. An access to this register after accessing the CSR register clears the TOF bit. 7 0 MSB LSB 76/167 1 ALTERNATE COUNTER LOW REGISTER (ACLR) Read Only Reset Value: 1111 1100 (FCh) This is an 8-bit register that contains the low part of the counter value. A write to this register resets the counter. An access to this register after an access to CSR register does not clear the TOF bit in the CSR register. 7 0 MSB LSB INPUT CAPTURE 2 HIGH REGISTER (IC2HR) Read Only Reset Value: Undefined This is an 8-bit read only register that contains the high part of the counter value (transferred by the Input Capture 2 event). 7 0 MSB LSB INPUT CAPTURE 2 LOW REGISTER (IC2LR) Read Only Reset Value: Undefined This is an 8-bit read only register that contains the low part of the counter value (transferred by the Input Capture 2 event). 7 0 MSB LSB ST72324B 16-BIT TIMER (Cont’d) Table 17. 16-Bit Timer Register Map and Reset Values Address (Hex.) Register Label 7 6 5 4 3 2 1 0 Timer A: 32 Timer B: 42 Timer A: 31 Timer B: 41 Timer A: 33 Timer B: 43 Timer A: 34 Timer B: 44 Timer A: 35 Timer B: 45 Timer A: 36 Timer B: 46 Timer A: 37 Timer B: 47 Timer A: 3E Timer B: 4E Timer A: 3F Timer B: 4F Timer A: 38 Timer B: 48 Timer A: 39 Timer B: 49 Timer A: 3A Timer B: 4A Timer A: 3B Timer B: 4B Timer A: 3C Timer B: 4C Timer A: 3D Timer B: 4D CR1 Reset Value CR2 Reset Value CSR Reset Value IC1HR Reset Value IC1LR Reset Value OC1HR Reset Value OC1LR Reset Value OC2HR Reset Value OC2LR Reset Value CHR Reset Value CLR Reset Value ACHR Reset Value ACLR Reset Value IC2HR Reset Value IC2LR Reset Value ICIE 0 OC1E 0 ICF1 x MSB x MSB x MSB 1 MSB 0 MSB 1 MSB 0 MSB 1 MSB 1 MSB 1 MSB 1 MSB x MSB x OCIE 0 OC2E1 0 OCF1 x TOIE 0 OPM 0 TOF x FOLV2 0 PWM 0 ICF2 x FOLV1 0 CC1 0 OCF2 x OLVL2 0 CC0 0 TIMD 0 IEDG1 0 IEDG2 0 x x x x x x x x x x x x x 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 1 1 0 x x x x x x x x x x x x OLVL1 0 EXEDG 0 x LSB x LSB x LSB 0 LSB 0 LSB 0 LSB 0 LSB 1 LSB 0 LSB 1 LSB 0 LSB x LSB x 77/167 1 ST72324B 10.4 SERIAL PERIPHERAL INTERFACE (SPI) 10.4.1 Introduction The Serial Peripheral Interface (SPI) allows fullduplex, synchronous, serial communication with external devices. An SPI system may consist of a master and one or more slaves however the SPI interface can not be a master in a multi-master system. 10.4.2 Main Features ■ Full duplex synchronous transfers (on 3 lines) ■ Simplex synchronous transfers (on 2 lines) ■ Master or slave operation ■ Six master mode frequencies (fCPU/4 max.) ■ fCPU/2 max. slave mode frequency (see note) ■ SS Management by software or hardware ■ Programmable clock polarity and phase ■ End of transfer interrupt flag ■ Write collision, Master Mode Fault and Overrun flags Note: In slave mode, continuous transmission is not possible at maximum frequency due to the software overhead for clearing status flags and to initiate the next transmission sequence. 10.4.3 General Description Figure 46 shows the serial peripheral interface (SPI) block diagram. There are 3 registers: – SPI Control Register (SPICR) – SPI Control/Status Register (SPICSR) – SPI Data Register (SPIDR) The SPI is connected to external devices through 4 pins: – MISO: Master In / Slave Out data – MOSI: Master Out / Slave In data – SCK: Serial Clock out by SPI masters and input by SPI slaves Figure 46. Serial Peripheral Interface Block Diagram Data/Address Bus SPIDR Read Interrupt request Read Buffer MOSI MISO 8-Bit Shift Register SPICSR 7 SPIF WCOL OVR MODF SOD bit SS SPI STATE CONTROL 7 SPIE MASTER CONTROL SERIAL CLOCK GENERATOR 78/167 1 SOD SSM SSI Write SCK SS 0 0 1 0 SPICR 0 SPE SPR2 MSTR CPOL CPHA SPR1 SPR0 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) – SS: Slave select: This input signal acts as a ‘chip select’ to let the SPI master communicate with slaves individually and to avoid contention on the data lines. Slave SS inputs can be driven by standard I/O ports on the master MCU. 10.4.3.1 Functional Description A basic example of interconnections between a single master and a single slave is illustrated in Figure 47. The MOSI pins are connected together and the MISO pins are connected together. In this way data is transferred serially between master and slave (most significant bit first). The communication is always initiated by the master. When the master device transmits data to a slave device via MOSI pin, the slave device responds by sending data to the master device via the MISO pin. This implies full duplex communication with both data out and data in synchronized with the same clock signal (which is provided by the master device via the SCK pin). To use a single data line, the MISO and MOSI pins must be connected at each node ( in this case only simplex communication is possible). Four possible data/clock timing relationships may be chosen (see Figure 50) but master and slave must be programmed with the same timing mode. Figure 47. Single Master/ Single Slave Application SLAVE MASTER MSBit LSBit 8-BIT SHIFT REGISTER SPI CLOCK GENERATOR MSBit MISO MISO MOSI MOSI SCK SS LSBit 8-BIT SHIFT REGISTER SCK +5V SS Not used if SS is managed by software 79/167 1 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) 10.4.3.2 Slave Select Management As an alternative to using the SS pin to control the Slave Select signal, the application can choose to manage the Slave Select signal by software. This is configured by the SSM bit in the SPICSR register (see Figure 49) In software management, the external SS pin is free for other application uses and the internal SS signal level is driven by writing to the SSI bit in the SPICSR register. In Master mode: – SS internal must be held high continuously In Slave Mode: There are two cases depending on the data/clock timing relationship (see Figure 48): If CPHA=1 (data latched on 2nd clock edge): – SS internal must be held low during the entire transmission. This implies that in single slave applications the SS pin either can be tied to VSS, or made free for standard I/O by managing the SS function by software (SSM= 1 and SSI=0 in the in the SPICSR register) If CPHA=0 (data latched on 1st clock edge): – SS internal must be held low during byte transmission and pulled high between each byte to allow the slave to write to the shift register. If SS is not pulled high, a Write Collision error will occur when the slave writes to the shift register (see Section 10.4.5.3). Figure 48. Generic SS Timing Diagram MOSI/MISO Byte 1 Byte 2 Master SS Slave SS (if CPHA=0) Slave SS (if CPHA=1) Figure 49. Hardware/Software Slave Select Management SSM bit 80/167 1 SSI bit 1 SS external pin 0 SS internal Byte 3 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) 10.4.3.3 Master Mode Operation In master mode, the serial clock is output on the SCK pin. The clock frequency, polarity and phase are configured by software (refer to the description of the SPICSR register). Note: The idle state of SCK must correspond to the polarity selected in the SPICSR register (by pulling up SCK if CPOL=1 or pulling down SCK if CPOL=0). To operate the SPI in master mode, perform the following steps in order: 1. Write to the SPICR register: – Select the clock frequency by configuring the SPR[2:0] bits. – Select the clock polarity and clock phase by configuring the CPOL and CPHA bits. Figure 50 shows the four possible configurations. Note: The slave must have the same CPOL and CPHA settings as the master. 2. Write to the SPICSR register: – Either set the SSM bit and set the SSI bit or clear the SSM bit and tie the SS pin high for the complete byte transmit sequence. 3. Write to the SPICR register: – Set the MSTR and SPE bits Note: MSTR and SPE bits remain set only if SS is high). Important note: if the SPICSR register is not written first, the SPICR register setting (MSTR bit) may be not taken into account. The transmit sequence begins when software writes a byte in the SPIDR register. 10.4.3.4 Master Mode Transmit Sequence When software writes to the SPIDR register, the data byte is loaded into the 8-bit shift register and then shifted out serially to the MOSI pin most significant bit first. When data transfer is complete: – The SPIF bit is set by hardware – An interrupt request is generated if the SPIE bit is set and the interrupt mask in the CCR register is cleared. Clearing the SPIF bit is performed by the following software sequence: 1. An access to the SPICSR register while the SPIF bit is set 2. A read to the SPIDR register. Note: While the SPIF bit is set, all writes to the SPIDR register are inhibited until the SPICSR register is read. 10.4.3.5 Slave Mode Operation In slave mode, the serial clock is received on the SCK pin from the master device. To operate the SPI in slave mode: 1. Write to the SPICSR register to perform the following actions: – Select the clock polarity and clock phase by configuring the CPOL and CPHA bits (see Figure 50). Note: The slave must have the same CPOL and CPHA settings as the master. – Manage the SS pin as described in Section 10.4.3.2 and Figure 48. If CPHA=1 SS must be held low continuously. If CPHA=0 SS must be held low during byte transmission and pulled up between each byte to let the slave write in the shift register. 2. Write to the SPICR register to clear the MSTR bit and set the SPE bit to enable the SPI I/O functions. 10.4.3.6 Slave Mode Transmit Sequence When software writes to the SPIDR register, the data byte is loaded into the 8-bit shift register and then shifted out serially to the MISO pin most significant bit first. The transmit sequence begins when the slave device receives the clock signal and the most significant bit of the data on its MOSI pin. When data transfer is complete: – The SPIF bit is set by hardware – An interrupt request is generated if SPIE bit is set and interrupt mask in the CCR register is cleared. Clearing the SPIF bit is performed by the following software sequence: 1. An access to the SPICSR register while the SPIF bit is set. 2. A write or a read to the SPIDR register. Notes: While the SPIF bit is set, all writes to the SPIDR register are inhibited until the SPICSR register is read. The SPIF bit can be cleared during a second transmission; however, it must be cleared before the second SPIF bit in order to prevent an Overrun condition (see Section 10.4.5.2). 81/167 1 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) 10.4.4 Clock Phase and Clock Polarity Four possible timing relationships may be chosen by software, using the CPOL and CPHA bits (See Figure 50). Note: The idle state of SCK must correspond to the polarity selected in the SPICSR register (by pulling up SCK if CPOL=1 or pulling down SCK if CPOL=0). The combination of the CPOL clock polarity and CPHA (clock phase) bits selects the data capture clock edge Figure 50, shows an SPI transfer with the four combinations of the CPHA and CPOL bits. The diagram may be interpreted as a master or slave timing diagram where the SCK pin, the MISO pin, the MOSI pin are directly connected between the master and the slave device. Note: If CPOL is changed at the communication byte boundaries, the SPI must be disabled by resetting the SPE bit. Figure 50. Data Clock Timing Diagram CPHA =1 SCK (CPOL = 1) SCK (CPOL = 0) MISO (from master) MOSI (from slave) MSBit Bit 6 Bit 5 Bit 4 Bit3 Bit 2 Bit 1 LSBit MSBit Bit 6 Bit 5 Bit 4 Bit3 Bit 2 Bit 1 LSBit SS (to slave) CAPTURE STROBE CPHA =0 SCK (CPOL = 1) SCK (CPOL = 0) MISO (from master) MOSI (from slave) MSBit MSBit Bit 6 Bit 5 Bit 4 Bit3 Bit 2 Bit 1 LSBit Bit 6 Bit 5 Bit 4 Bit3 Bit 2 Bit 1 LSBit SS (to slave) CAPTURE STROBE Note: This figure should not be used as a replacement for parametric information. Refer to the Electrical Characteristics chapter. 82/167 1 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) 10.4.5 Error Flags 10.4.5.1 Master Mode Fault (MODF) Master mode fault occurs when the master device has its SS pin pulled low. When a Master mode fault occurs: – The MODF bit is set and an SPI interrupt request is generated if the SPIE bit is set. – The SPE bit is reset. This blocks all output from the device and disables the SPI peripheral. – The MSTR bit is reset, thus forcing the device into slave mode. Clearing the MODF bit is done through a software sequence: 1. A read access to the SPICSR register while the MODF bit is set. 2. A write to the SPICR register. Notes: To avoid any conflicts in an application with multiple slaves, the SS pin must be pulled high during the MODF bit clearing sequence. The SPE and MSTR bits may be restored to their original state during or after this clearing sequence. Hardware does not allow the user to set the SPE and MSTR bits while the MODF bit is set except in the MODF bit clearing sequence. 10.4.5.2 Overrun Condition (OVR) An overrun condition occurs, when the master device has sent a data byte and the slave device has not cleared the SPIF bit issued from the previously transmitted byte. When an Overrun occurs: – The OVR bit is set and an interrupt request is generated if the SPIE bit is set. In this case, the receiver buffer contains the byte sent after the SPIF bit was last cleared. A read to the SPIDR register returns this byte. All other bytes are lost. The OVR bit is cleared by reading the SPICSR register. 10.4.5.3 Write Collision Error (WCOL) A write collision occurs when the software tries to write to the SPIDR register while a data transfer is taking place with an external device. When this happens, the transfer continues uninterrupted; and the software write will be unsuccessful. Write collisions can occur both in master and slave mode. See also Section 10.4.3.2 Slave Select Management. Note: a "read collision" will never occur since the received data byte is placed in a buffer in which access is always synchronous with the MCU operation. The WCOL bit in the SPICSR register is set if a write collision occurs. No SPI interrupt is generated when the WCOL bit is set (the WCOL bit is a status flag only). Clearing the WCOL bit is done through a software sequence (see Figure 51). Figure 51. Clearing the WCOL bit (Write Collision Flag) Software Sequence Clearing sequence after SPIF = 1 (end of a data byte transfer) 1st Step Read SPICSR RESULT 2nd Step Read SPIDR SPIF =0 WCOL=0 Clearing sequence before SPIF = 1 (during a data byte transfer) 1st Step Read SPICSR RESULT 2nd Step Read SPIDR WCOL=0 Note: Writing to the SPIDR register instead of reading it does not reset the WCOL bit 83/167 1 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) 10.4.5.4 Single Master Systems A typical single master system may be configured, using an MCU as the master and four MCUs as slaves (see Figure 52). The master device selects the individual slave devices by using four pins of a parallel port to control the four SS pins of the slave devices. The SS pins are pulled high during reset since the master device ports will be forced to be inputs at that time, thus disabling the slave devices. Note: To prevent a bus conflict on the MISO line the master allows only one active slave device during a transmission. For more security, the slave device may respond to the master with the received data byte. Then the master will receive the previous byte back from the slave device if all MISO and MOSI pins are connected and the slave has not written to its SPIDR register. Other transmission security methods can use ports for handshake lines or data bytes with command fields. Figure 52. Single Master / Multiple Slave Configuration SS SCK Slave MCU Slave MCU MOSI MISO MOSI MISO SCK Master MCU 5V 84/167 1 SS Ports MOSI MISO SS SS SCK SS SCK Slave MCU SCK Slave MCU MOSI MISO MOSI MISO ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) 10.4.6 Low Power Modes Mode WAIT HALT Description No effect on SPI. SPI interrupt events cause the device to exit from WAIT mode. SPI registers are frozen. In HALT mode, the SPI is inactive. SPI operation resumes when the MCU is woken up by an interrupt with “exit from HALT mode” capability. The data received is subsequently read from the SPIDR register when the software is running (interrupt vector fetching). If several data are received before the wakeup event, then an overrun error is generated. This error can be detected after the fetch of the interrupt routine that woke up the device. Note: When waking up from Halt mode, if the SPI remains in Slave mode, it is recommended to perform an extra communications cycle to bring the SPI from Halt mode state to normal state. If the SPI exits from Slave mode, it returns to normal state immediately. Caution: The SPI can wake up the ST7 from Halt mode only if the Slave Select signal (external SS pin or the SSI bit in the SPICSR register) is low when the ST7 enters Halt mode. So if Slave selection is configured as external (see Section 10.4.3.2), make sure the master drives a low level on the SS pin when the slave enters Halt mode. 10.4.7 Interrupts Interrupt Event 10.4.6.1 Using the SPI to wakeup the MCU from Halt mode In slave configuration, the SPI is able to wakeup the ST7 device from HALT mode through a SPIF interrupt. The data received is subsequently read from the SPIDR register when the software is running (interrupt vector fetch). If multiple data transfers have been performed before software clears the SPIF bit, then the OVR bit is set by hardware. SPI End of Transfer Event Master Mode Fault Event Overrun Error Event Flag Enable Control Bit SPIF MODF OVR SPIE Exit from Wait Exit from Halt Yes Yes Yes No Yes No Note: The SPI interrupt events are connected to the same interrupt vector (see Interrupts chapter). They generate an interrupt if the corresponding Enable Control Bit is set and the interrupt mask in 85/167 1 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) 10.4.8 Register Description CONTROL REGISTER (SPICR) Read/Write Reset Value: 0000 xxxx (0xh) 7 SPIE 0 SPE SPR2 MSTR CPOL CPHA SPR1 SPR0 Bit 7 = SPIE Serial Peripheral Interrupt Enable. This bit is set and cleared by software. 0: Interrupt is inhibited 1: An SPI interrupt is generated whenever SPIF=1, MODF=1 or OVR=1 in the SPICSR register Bit 6 = SPE Serial Peripheral Output Enable. This bit is set and cleared by software. It is also cleared by hardware when, in master mode, SS=0 (see Section 10.4.5.1 Master Mode Fault (MODF)). The SPE bit is cleared by reset, so the SPI peripheral is not initially connected to the external pins. 0: I/O pins free for general purpose I/O 1: SPI I/O pin alternate functions enabled Bit 5 = SPR2 Divider Enable. This bit is set and cleared by software and is cleared by reset. It is used with the SPR[1:0] bits to set the baud rate. Refer to Table 18 SPI Master mode SCK Frequency. 0: Divider by 2 enabled 1: Divider by 2 disabled Note: This bit has no effect in slave mode. Bit 4 = MSTR Master Mode. This bit is set and cleared by software. It is also cleared by hardware when, in master mode, SS=0 (see Section 10.4.5.1 Master Mode Fault (MODF)). 0: Slave mode 1: Master mode. The function of the SCK pin changes from an input to an output and the functions of the MISO and MOSI pins are reversed. 86/167 1 Bit 3 = CPOL Clock Polarity. This bit is set and cleared by software. This bit determines the idle state of the serial Clock. The CPOL bit affects both the master and slave modes. 0: SCK pin has a low level idle state 1: SCK pin has a high level idle state Note: If CPOL is changed at the communication byte boundaries, the SPI must be disabled by resetting the SPE bit. Bit 2 = CPHA Clock Phase. This bit is set and cleared by software. 0: The first clock transition is the first data capture edge. 1: The second clock transition is the first capture edge. Note: The slave must have the same CPOL and CPHA settings as the master. Bits 1:0 = SPR[1:0] Serial Clock Frequency. These bits are set and cleared by software. Used with the SPR2 bit, they select the baud rate of the SPI serial clock SCK output by the SPI in master mode. Note: These 2 bits have no effect in slave mode. Table 18. SPI Master mode SCK Frequency Serial Clock SPR2 SPR1 SPR0 fCPU/4 1 0 0 fCPU/8 0 0 0 fCPU/16 0 0 1 fCPU/32 1 1 0 fCPU/64 0 1 0 fCPU/128 0 1 1 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) CONTROL/STATUS REGISTER (SPICSR) Read/Write (some bits Read Only) Reset Value: 0000 0000 (00h) 7 SPIF Bit 3 = Reserved, must be kept cleared. 0 WCOL OVR MODF - SOD SSM SSI Bit 7 = SPIF Serial Peripheral Data Transfer Flag (Read only). This bit is set by hardware when a transfer has been completed. An interrupt is generated if SPIE=1 in the SPICR register. It is cleared by a software sequence (an access to the SPICSR register followed by a write or a read to the SPIDR register). 0: Data transfer is in progress or the flag has been cleared. 1: Data transfer between the device and an external device has been completed. Note: While the SPIF bit is set, all writes to the SPIDR register are inhibited until the SPICSR register is read. Bit 6 = WCOL Write Collision status (Read only). This bit is set by hardware when a write to the SPIDR register is done during a transmit sequence. It is cleared by a software sequence (see Figure 51). 0: No write collision occurred 1: A write collision has been detected Bit 2 = SOD SPI Output Disable. This bit is set and cleared by software. When set, it disables the alternate function of the SPI output (MOSI in master mode / MISO in slave mode) 0: SPI output enabled (if SPE=1) 1: SPI output disabled Bit 1 = SSM SS Management. This bit is set and cleared by software. When set, it disables the alternate function of the SPI SS pin and uses the SSI bit value instead. See Section 10.4.3.2 Slave Select Management. 0: Hardware management (SS managed by external pin) 1: Software management (internal SS signal controlled by SSI bit. External SS pin free for general-purpose I/O) Bit 0 = SSI SS Internal Mode. This bit is set and cleared by software. It acts as a ‘chip select’ by controlling the level of the SS slave select signal when the SSM bit is set. 0 : Slave selected 1 : Slave deselected DATA I/O REGISTER (SPIDR) Read/Write Reset Value: Undefined 7 Bit 5 = OVR SPI Overrun error (Read only). This bit is set by hardware when the byte currently being received in the shift register is ready to be transferred into the SPIDR register while SPIF = 1 (See Section 10.4.5.2). An interrupt is generated if SPIE = 1 in SPICR register. The OVR bit is cleared by software reading the SPICSR register. 0: No overrun error 1: Overrun error detected Bit 4 = MODF Mode Fault flag (Read only). This bit is set by hardware when the SS pin is pulled low in master mode (see Section 10.4.5.1 Master Mode Fault (MODF)). An SPI interrupt can be generated if SPIE=1 in the SPICSR register. This bit is cleared by a software sequence (An access to the SPICR register while MODF=1 followed by a write to the SPICR register). 0: No master mode fault detected 1: A fault in master mode has been detected D7 0 D6 D5 D4 D3 D2 D1 D0 The SPIDR register is used to transmit and receive data on the serial bus. In a master device, a write to this register will initiate transmission/reception of another byte. Notes: During the last clock cycle the SPIF bit is set, a copy of the received data byte in the shift register is moved to a buffer. When the user reads the serial peripheral data I/O register, the buffer is actually being read. While the SPIF bit is set, all writes to the SPIDR register are inhibited until the SPICSR register is read. Warning: A write to the SPIDR register places data directly into the shift register for transmission. A read to the SPIDR register returns the value located in the buffer and not the content of the shift register (see Figure 46). 87/167 1 ST72324B SERIAL PERIPHERAL INTERFACE (Cont’d) Table 19. SPI Register Map and Reset Values Address (Hex.) 0021h 0022h 0023h 88/167 1 Register Label 7 6 5 4 3 2 1 0 SPIDR Reset Value SPICR Reset Value SPICSR Reset Value MSB x SPIE 0 SPIF 0 x SPE 0 WCOL 0 x SPR2 0 OR 0 x MSTR 0 MODF 0 x CPOL x x CPHA x SOD 0 x SPR1 x SSM 0 LSB x SPR0 x SSI 0 0 ST72324B 10.5 SERIAL COMMUNICATIONS INTERFACE (SCI) 10.5.1 Introduction The Serial Communications Interface (SCI) offers a flexible means of full-duplex data exchange with external equipment requiring an industry standard NRZ asynchronous serial data format. The SCI offers a very wide range of baud rates using two baud rate generator systems. 10.5.2 Main Features ■ Full duplex, asynchronous communications ■ NRZ standard format (Mark/Space) ■ Dual baud rate generator systems ■ Independently programmable transmit and receive baud rates up to 500K baud. ■ Programmable data word length (8 or 9 bits) ■ Receive buffer full, Transmit buffer empty and End of Transmission flags ■ Two receiver wake-up modes: – Address bit (MSB) – Idle line ■ Muting function for multiprocessor configurations ■ Separate enable bits for Transmitter and Receiver ■ Four error detection flags: – Overrun error – Noise error – Frame error – Parity error ■ Five interrupt sources with flags: – Transmit data register empty – Transmission complete – Receive data register full – Idle line received – Overrun error detected ■ Parity control: – Transmits parity bit – Checks parity of received data byte ■ Reduced power consumption mode 10.5.3 General Description The interface is externally connected to another device by two pins (see Figure 2.): – TDO: Transmit Data Output. When the transmitter and the receiver are disabled, the output pin returns to its I/O port configuration. When the transmitter and/or the receiver are enabled and nothing is to be transmitted, the TDO pin is at high level. – RDI: Receive Data Input is the serial data input. Oversampling techniques are used for data recovery by discriminating between valid incoming data and noise. Through these pins, serial data is transmitted and received as frames comprising: – An Idle Line prior to transmission or reception – A start bit – A data word (8 or 9 bits) least significant bit first – A Stop bit indicating that the frame is complete. This interface uses two types of baud rate generator: – A conventional type for commonly-used baud rates, – An extended type with a prescaler offering a very wide range of baud rates even with non-standard oscillator frequencies. 89/167 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) Figure 53. SCI Block Diagram Write Read (DATA REGISTER) DR Received Data Register (RDR) Transmit Data Register (TDR) TDO Received Shift Register Transmit Shift Register RDI CR1 R8 TRANSMIT WAKE UP CONTROL UNIT T8 SCID M WAKE PCE PS PIE RECEIVER CLOCK RECEIVER CONTROL CR2 SR TIE TCIE RIE ILIE TE RE RWU SBK TDRE TC RDRF IDLE OR NF FE SCI INTERRUPT CONTROL TRANSMITTER CLOCK TRANSMITTER RATE fCPU CONTROL /16 /PR BRR SCP1 SCP0 SCT2 SCT1 SCT0 SCR2 SCR1SCR0 RECEIVER RATE CONTROL CONVENTIONAL BAUD RATE GENERATOR 90/167 1 PE ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) 10.5.4 Functional Description The block diagram of the Serial Control Interface, is shown in Figure 1.. It contains 6 dedicated registers: – Two control registers (SCICR1 & SCICR2) – A status register (SCISR) – A baud rate register (SCIBRR) – An extended prescaler receiver register (SCIERPR) – An extended prescaler transmitter register (SCIETPR) Refer to the register descriptions in Section 0.1.7 for the definitions of each bit. 10.5.4.1 Serial Data Format Word length may be selected as being either 8 or 9 bits by programming the M bit in the SCICR1 register (see Figure 1.). The TDO pin is in low state during the start bit. The TDO pin is in high state during the stop bit. An Idle character is interpreted as an entire frame of “1”s followed by the start bit of the next frame which contains data. A Break character is interpreted on receiving “0”s for some multiple of the frame period. At the end of the last break frame the transmitter inserts an extra “1” bit to acknowledge the start bit. Transmission and reception are driven by their own baud rate generator. Figure 54. Word Length Programming 9-bit Word length (M bit is set) Possible Parity Bit Data Frame Start Bit Bit0 Bit2 Bit1 Bit3 Bit4 Bit5 Bit6 Start Bit Break Frame Extra ’1’ Possible Parity Bit Data Frame Bit0 Bit8 Next Stop Start Bit Bit Idle Frame 8-bit Word length (M bit is reset) Start Bit Bit7 Next Data Frame Bit1 Bit2 Bit3 Bit4 Bit5 Bit6 Bit7 Start Bit Next Data Frame Stop Bit Next Start Bit Idle Frame Start Bit Break Frame Extra Start Bit ’1’ 91/167 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) 10.5.4.2 Transmitter The transmitter can send data words of either 8 or 9 bits depending on the M bit status. When the M bit is set, word length is 9 bits and the 9th bit (the MSB) has to be stored in the T8 bit in the SCICR1 register. Character Transmission During an SCI transmission, data shifts out least significant bit first on the TDO pin. In this mode, the SCIDR register consists of a buffer (TDR) between the internal bus and the transmit shift register (see Figure 1.). Procedure – Select the M bit to define the word length. – Select the desired baud rate using the SCIBRR and the SCIETPR registers. – Set the TE bit to assign the TDO pin to the alternate function and to send a idle frame as first transmission. – Access the SCISR register and write the data to send in the SCIDR register (this sequence clears the TDRE bit). Repeat this sequence for each data to be transmitted. Clearing the TDRE bit is always performed by the following software sequence: 1. An access to the SCISR register 2. A write to the SCIDR register The TDRE bit is set by hardware and it indicates: – The TDR register is empty. – The data transfer is beginning. – The next data can be written in the SCIDR register without overwriting the previous data. This flag generates an interrupt if the TIE bit is set and the I bit is cleared in the CCR register. When a transmission is taking place, a write instruction to the SCIDR register stores the data in the TDR register and which is copied in the shift register at the end of the current transmission. When no transmission is taking place, a write instruction to the SCIDR register places the data directly in the shift register, the data transmission starts, and the TDRE bit is immediately set. 92/167 1 When a frame transmission is complete (after the stop bit) the TC bit is set and an interrupt is generated if the TCIE is set and the I bit is cleared in the CCR register. Clearing the TC bit is performed by the following software sequence: 1. An access to the SCISR register 2. A write to the SCIDR register Note: The TDRE and TC bits are cleared by the same software sequence. Break Characters Setting the SBK bit loads the shift register with a break character. The break frame length depends on the M bit (see Figure 2.). As long as the SBK bit is set, the SCI send break frames to the TDO pin. After clearing this bit by software the SCI insert a logic 1 bit at the end of the last break frame to guarantee the recognition of the start bit of the next frame. Idle Characters Setting the TE bit drives the SCI to send an idle frame before the first data frame. Clearing and then setting the TE bit during a transmission sends an idle frame after the current word. Note: Resetting and setting the TE bit causes the data in the TDR register to be lost. Therefore the best time to toggle the TE bit is when the TDRE bit is set i.e. before writing the next byte in the SCIDR. ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) 10.5.4.3 Receiver The SCI can receive data words of either 8 or 9 bits. When the M bit is set, word length is 9 bits and the MSB is stored in the R8 bit in the SCICR1 register. Character reception During a SCI reception, data shifts in least significant bit first through the RDI pin. In this mode, the SCIDR register consists or a buffer (RDR) between the internal bus and the received shift register (see Figure 1.). Procedure – Select the M bit to define the word length. – Select the desired baud rate using the SCIBRR and the SCIERPR registers. – Set the RE bit, this enables the receiver which begins searching for a start bit. When a character is received: – The RDRF bit is set. It indicates that the content of the shift register is transferred to the RDR. – An interrupt is generated if the RIE bit is set and the I bit is cleared in the CCR register. – The error flags can be set if a frame error, noise or an overrun error has been detected during reception. Clearing the RDRF bit is performed by the following software sequence done by: 1. An access to the SCISR register 2. A read to the SCIDR register. The RDRF bit must be cleared before the end of the reception of the next character to avoid an overrun error. Break Character When a break character is received, the SCI handles it as a framing error. Idle Character When a idle frame is detected, there is the same procedure as a data received character plus an interrupt if the ILIE bit is set and the I bit is cleared in the CCR register. Overrun Error An overrun error occurs when a character is received when RDRF has not been reset. Data can not be transferred from the shift register to the RDR register as long as the RDRF bit is not cleared. When a overrun error occurs: – The OR bit is set. – The RDR content will not be lost. – The shift register will be overwritten. – An interrupt is generated if the RIE bit is set and the I bit is cleared in the CCR register. The OR bit is reset by an access to the SCISR register followed by a SCIDR register read operation. Noise Error Oversampling techniques are used for data recovery by discriminating between valid incoming data and noise. Normal data bits are considered valid if three consecutive samples (8th, 9th, 10th) have the same bit value, otherwise the NF flag is set. In the case of start bit detection, the NF flag is set on the basis of an algorithm combining both valid edge detection and three samples (8th, 9th, 10th). Therefore, to prevent the NF flag getting set during start bit reception, there should be a valid edge detection as well as three valid samples. When noise is detected in a frame: – The NF flag is set at the rising edge of the RDRF bit. – Data is transferred from the Shift register to the SCIDR register. – No interrupt is generated. However this bit rises at the same time as the RDRF bit which itself generates an interrupt. The NF flag is reset by a SCISR register read operation followed by a SCIDR register read operation. During reception, if a false start bit is detected (e.g. 8th, 9th, 10th samples are 011,101,110), the frame is discarded and the receiving sequence is not started for this frame. There is no RDRF bit set for this frame and the NF flag is set internally (not accessible to the user). This NF flag is accessible along with the RDRF bit when a next valid frame is received. Note: If the application Start Bit is not long enough to match the above requirements, then the NF Flag may get set due to the short Start Bit. In this case, the NF flag may be ignored by the application software when the first valid byte is received. See also Section 0.1.4.10 . 93/167 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) Figure 55. SCI Baud Rate and Extended Prescaler Block Diagram TRANSMITTER CLOCK EXTENDED PRESCALER TRANSMITTER RATE CONTROL SCIETPR EXTENDED TRANSMITTER PRESCALER REGISTER SCIERPR EXTENDED RECEIVER PRESCALER REGISTER RECEIVER CLOCK EXTENDED PRESCALER RECEIVER RATE CONTROL EXTENDED PRESCALER fCPU TRANSMITTER RATE CONTROL /16 /PR SCIBRR SCP1 SCP0 SCT2 SCT1 SCT0 SCR2 SCR1SCR0 RECEIVER RATE CONTROL CONVENTIONAL BAUD RATE GENERATOR 94/167 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) Framing Error A framing error is detected when: – The stop bit is not recognized on reception at the expected time, following either a de-synchronization or excessive noise. – A break is received. When the framing error is detected: – the FE bit is set by hardware – Data is transferred from the Shift register to the SCIDR register. – No interrupt is generated. However this bit rises at the same time as the RDRF bit which itself generates an interrupt. The FE bit is reset by a SCISR register read operation followed by a SCIDR register read operation. 10.5.4.4 Conventional Baud Rate Generation The baud rate for the receiver and transmitter (Rx and Tx) are set independently and calculated as follows: Tx = fCPU (16*PR)*TR Rx = fCPU (16*PR)*RR with: PR = 1, 3, 4 or 13 (see SCP[1:0] bits) TR = 1, 2, 4, 8, 16, 32, 64,128 (see SCT[2:0] bits) RR = 1, 2, 4, 8, 16, 32, 64,128 (see SCR[2:0] bits) All these bits are in the SCIBRR register. Example: If fCPU is 8 MHz (normal mode) and if PR=13 and TR=RR=1, the transmit and receive baud rates are 38400 baud. Note: the baud rate registers MUST NOT be changed while the transmitter or the receiver is enabled. 10.5.4.5 Extended Baud Rate Generation The extended prescaler option gives a very fine tuning on the baud rate, using a 255 value prescaler, whereas the conventional Baud Rate Generator retains industry standard software compatibility. The extended baud rate generator block diagram is described in the Figure 3.. The output clock rate sent to the transmitter or to the receiver will be the output from the 16 divider divided by a factor ranging from 1 to 255 set in the SCIERPR or the SCIETPR register. Note: the extended prescaler is activated by setting the SCIETPR or SCIERPR register to a value other than zero. The baud rates are calculated as follows: fCPU fCPU Rx = Tx = 16*ERPR*(PR*RR) 16*ETPR*(PR*TR) with: ETPR = 1,..,255 (see SCIETPR register) ERPR = 1,.. 255 (see SCIERPR register) 10.5.4.6 Receiver Muting and Wake-up Feature In multiprocessor configurations it is often desirable that only the intended message recipient should actively receive the full message contents, thus reducing redundant SCI service overhead for all non addressed receivers. The non addressed devices may be placed in sleep mode by means of the muting function. Setting the RWU bit by software puts the SCI in sleep mode: All the reception status bits can not be set. All the receive interrupts are inhibited. A muted receiver may be awakened by one of the following two ways: – by Idle Line detection if the WAKE bit is reset, – by Address Mark detection if the WAKE bit is set. Receiver wakes-up by Idle Line detection when the Receive line has recognised an Idle Frame. Then the RWU bit is reset by hardware but the IDLE bit is not set. Receiver wakes-up by Address Mark detection when it received a “1” as the most significant bit of a word, thus indicating that the message is an address. The reception of this particular word wakes up the receiver, resets the RWU bit and sets the RDRF bit, which allows the receiver to receive this word normally and to use it as an address word. Caution: In Mute mode, do not write to the SCICR2 register. If the SCI is in Mute mode during the read operation (RWU=1) and a address mark wake up event occurs (RWU is reset) before the write operation, the RWU bit will be set again by this write operation. Consequently the address byte is lost and the SCI is not woken up from Mute mode. 95/167 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) 10.5.4.7 Parity Control Parity control (generation of parity bit in transmission and parity checking in reception) can be enabled by setting the PCE bit in the SCICR1 register. Depending on the frame length defined by the M bit, the possible SCI frame formats are as listed in Table 1. Table 20. Frame Formats M bit 0 0 1 1 PCE bit 0 1 0 1 SCI frame | SB | 8 bit data | STB | | SB | 7-bit data | PB | STB | | SB | 9-bit data | STB | | SB | 8-bit data PB | STB | Legend: SB = Start Bit, STB = Stop Bit, PB = Parity Bit Note: In case of wake up by an address mark, the MSB bit of the data is taken into account and not the parity bit Even parity: the parity bit is calculated to obtain an even number of “1s” inside the frame made of the 7 or 8 LSB bits (depending on whether M is equal to 0 or 1) and the parity bit. Ex: data=00110101; 4 bits set => parity bit will be 0 if even parity is selected (PS bit = 0). Odd parity: the parity bit is calculated to obtain an odd number of “1s” inside the frame made of the 7 or 8 LSB bits (depending on whether M is equal to 0 or 1) and the parity bit. Ex: data=00110101; 4 bits set => parity bit will be 1 if odd parity is selected (PS bit = 1). Transmission mode: If the PCE bit is set then the MSB bit of the data written in the data register is not transmitted but is changed by the parity bit. Reception mode: If the PCE bit is set then the interface checks if the received data byte has an 96/167 1 even number of “1s” if even parity is selected (PS=0) or an odd number of “1s” if odd parity is selected (PS=1). If the parity check fails, the PE flag is set in the SCISR register and an interrupt is generated if PIE is set in the SCICR1 register. 10.5.4.8 SCI Clock Tolerance During reception, each bit is sampled 16 times. The majority of the 8th, 9th and 10th samples is considered as the bit value. For a valid bit detection, all the three samples should have the same value otherwise the noise flag (NF) is set. For example: if the 8th, 9th and 10th samples are 0, 1 and 1 respectively, then the bit value will be “1”, but the Noise Flag bit is be set because the three samples values are not the same. Consequently, the bit length must be long enough so that the 8th, 9th and 10th samples have the desired bit value. This means the clock frequency should not vary more than 6/16 (37.5%) within one bit. The sampling clock is resynchronized at each start bit, so that when receiving 10 bits (one start bit, 1 data byte, 1 stop bit), the clock deviation must not exceed 3.75%. Note: The internal sampling clock of the microcontroller samples the pin value on every falling edge. Therefore, the internal sampling clock and the time the application expects the sampling to take place may be out of sync. For example: If the baud rate is 15.625 kbaud (bit length is 64µs), then the 8th, 9th and 10th samples will be at 28µs, 32µs & 36µs respectively (the first sample starting ideally at 0µs). But if the falling edge of the internal clock occurs just before the pin value changes, the samples would then be out of sync by ~4us. This means the entire bit length must be at least 40µs (36µs for the 10th sample + 4µs for synchronization with the internal sampling clock). ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) 10.5.4.9 Clock Deviation Causes The causes which contribute to the total deviation are: – DTRA: Deviation due to transmitter error (Local oscillator error of the transmitter or the transmitter is transmitting at a different baud rate). – DQUANT: Error due to the baud rate quantisation of the receiver. – DREC: Deviation of the local oscillator of the receiver: This deviation can occur during the reception of one complete SCI message assuming that the deviation has been compensated at the beginning of the message. – DTCL: Deviation due to the transmission line (generally due to the transceivers) All the deviations of the system should be added and compared to the SCI clock tolerance: DTRA + DQUANT + DREC + DTCL < 3.75% 10.5.4.10 Noise Error Causes See also description of Noise error in Section 0.1.4.3 . Start bit The noise flag (NF) is set during start bit reception if one of the following conditions occurs: 1. A valid falling edge is not detected. A falling edge is considered to be valid if the 3 consecutive samples before the falling edge occurs are detected as '1' and, after the falling edge occurs, during the sampling of the 16 samples, if one of the samples numbered 3, 5 or 7 is detected as a “1”. 2. During sampling of the 16 samples, if one of the samples numbered 8, 9 or 10 is detected as a “1”. Therefore, a valid Start Bit must satisfy both the above conditions to prevent the Noise Flag getting set. Data Bits The noise flag (NF) is set during normal data bit reception if the following condition occurs: – During the sampling of 16 samples, if all three samples numbered 8, 9 and10 are not the same. The majority of the 8th, 9th and 10th samples is considered as the bit value. Therefore, a valid Data Bit must have samples 8, 9 and 10 at the same value to prevent the Noise Flag getting set. Figure 56. Bit Sampling in Reception Mode RDI LINE sampled values Sample clock 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 6/16 7/16 7/16 One bit time 97/167 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) 10.5.5 Low Power Modes Mode Description No effect on SCI. WAIT SCI interrupts cause the device to exit from Wait mode. SCI registers are frozen. HALT In Halt mode, the SCI stops transmitting/receiving until Halt mode is exited. 10.5.6 Interrupts The SCI interrupt events are connected to the same interrupt vector. These events generate an interrupt if the corresponding Enable Control Bit is set and the inter- 98/167 1 Interrupt Event Enable Exit Event Control from Flag Bit Wait Transmit Data Register TDRE Empty Transmission ComTC plete Received Data Ready RDRF to be Read Overrun Error Detected OR Idle Line Detected IDLE Parity Error PE Exit from Halt TIE Yes No TCIE Yes No Yes No Yes Yes Yes No No No RIE ILIE PIE rupt mask in the CC register is reset (RIM instruction). ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) 10.5.7 Register Description Note: The IDLE bit will not be set again until the RDRF bit has been set itself (i.e. a new idle line ocSTATUS REGISTER (SCISR) curs). Read Only Reset Value: 1100 0000 (C0h) Bit 3 = OR Overrun error. 7 0 This bit is set by hardware when the word currently being received in the shift register is ready to be TDRE TC RDRF IDLE OR NF FE PE transferred into the RDR register while RDRF=1. An interrupt is generated if RIE=1 in the SCICR2 register. It is cleared by a software sequence (an Bit 7 = TDRE Transmit data register empty. access to the SCISR register followed by a read to This bit is set by hardware when the content of the the SCIDR register). TDR register has been transferred into the shift 0: No Overrun error register. An interrupt is generated if the TIE bit=1 1: Overrun error is detected in the SCICR2 register. It is cleared by a software sequence (an access to the SCISR register folNote: When this bit is set RDR register content will lowed by a write to the SCIDR register). not be lost but the shift register will be overwritten. 0: Data is not transferred to the shift register 1: Data is transferred to the shift register Bit 2 = NF Noise flag. Note: Data will not be transferred to the shift regThis bit is set by hardware when noise is detected ister unless the TDRE bit is cleared. on a received frame. It is cleared by a software sequence (an access to the SCISR register followed by a read to the SCIDR register). Bit 6 = TC Transmission complete. 0: No noise is detected This bit is set by hardware when transmission of a 1: Noise is detected frame containing Data is complete. An interrupt is generated if TCIE=1 in the SCICR2 register. It is Note: This bit does not generate interrupt as it apcleared by a software sequence (an access to the pears at the same time as the RDRF bit which itSCISR register followed by a write to the SCIDR self generates an interrupt. register). 0: Transmission is not complete 1: Transmission is complete Bit 1 = FE Framing error. This bit is set by hardware when a de-synchronizaNote: TC is not set after the transmission of a Pretion, excessive noise or a break character is deamble or a Break. tected. It is cleared by a software sequence (an access to the SCISR register followed by a read to Bit 5 = RDRF Received data ready flag. the SCIDR register). This bit is set by hardware when the content of the 0: No Framing error is detected RDR register has been transferred to the SCIDR 1: Framing error or break character is detected register. An interrupt is generated if RIE=1 in the Note: This bit does not generate interrupt as it apSCICR2 register. It is cleared by a software sepears at the same time as the RDRF bit which itquence (an access to the SCISR register followed self generates an interrupt. If the word currently by a read to the SCIDR register). being transferred causes both frame error and 0: Data is not received overrun error, it will be transferred and only the OR 1: Received data is ready to be read bit will be set. Bit 4 = IDLE Idle line detect. This bit is set by hardware when a Idle Line is detected. An interrupt is generated if the ILIE=1 in the SCICR2 register. It is cleared by a software sequence (an access to the SCISR register followed by a read to the SCIDR register). 0: No Idle Line is detected 1: Idle Line is detected Bit 0 = PE Parity error. This bit is set by hardware when a parity error occurs in receiver mode. It is cleared by a software sequence (a read to the status register followed by an access to the SCIDR data register). An interrupt is generated if PIE=1 in the SCICR1 register. 0: No parity error 1: Parity error 99/167 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) CONTROL REGISTER 1 (SCICR1) Read/Write Bit 3 = WAKE Wake-Up method. This bit determines the SCI Wake-Up method, it is Reset Value: x000 0000 (x0h) set or cleared by software. 0: Idle Line 7 0 1: Address Mark R8 T8 SCID M WAKE PCE PS PIE Bit 7 = R8 Receive data bit 8. This bit is used to store the 9th bit of the received word when M=1. Bit 6 = T8 Transmit data bit 8. This bit is used to store the 9th bit of the transmitted word when M=1. Bit 5 = SCID Disabled for low power consumption When this bit is set the SCI prescalers and outputs are stopped and the end of the current byte transfer in order to reduce power consumption.This bit is set and cleared by software. 0: SCI enabled 1: SCI prescaler and outputs disabled Bit 4 = M Word length. This bit determines the word length. It is set or cleared by software. 0: 1 Start bit, 8 Data bits, 1 Stop bit 1: 1 Start bit, 9 Data bits, 1 Stop bit Note: The M bit must not be modified during a data transfer (both transmission and reception). 100/167 1 Bit 2 = PCE Parity control enable. This bit selects the hardware parity control (generation and detection). When the parity control is enabled, the computed parity is inserted at the MSB position (9th bit if M=1; 8th bit if M=0) and parity is checked on the received data. This bit is set and cleared by software. Once it is set, PCE is active after the current byte (in reception and in transmission). 0: Parity control disabled 1: Parity control enabled Bit 1 = PS Parity selection. This bit selects the odd or even parity when the parity generation/detection is enabled (PCE bit set). It is set and cleared by software. The parity will be selected after the current byte. 0: Even parity 1: Odd parity Bit 0 = PIE Parity interrupt enable. This bit enables the interrupt capability of the hardware parity control when a parity error is detected (PE bit set). It is set and cleared by software. 0: Parity error interrupt disabled 1: Parity error interrupt enabled. ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) CONTROL REGISTER 2 (SCICR2) Notes: Read/Write – During transmission, a “0” pulse on the TE bit (“0” followed by “1”) sends a preamble (idle line) Reset Value: 0000 0000 (00h) after the current word. 7 0 – When TE is set there is a 1 bit-time delay before the transmission starts. TIE TCIE RIE ILIE TE RE RWU SBK Caution: The TDO pin is free for general purpose I/O only when the TE and RE bits are both cleared (or if TE is never set). Bit 7 = TIE Transmitter interrupt enable. This bit is set and cleared by software. 0: Interrupt is inhibited Bit 2 = RE Receiver enable. 1: An SCI interrupt is generated whenever This bit enables the receiver. It is set and cleared TDRE=1 in the SCISR register by software. 0: Receiver is disabled Bit 6 = TCIE Transmission complete interrupt ena1: Receiver is enabled and begins searching for a ble start bit This bit is set and cleared by software. 0: Interrupt is inhibited Bit 1 = RWU Receiver wake-up. 1: An SCI interrupt is generated whenever TC=1 in This bit determines if the SCI is in mute mode or the SCISR register not. It is set and cleared by software and can be cleared by hardware when a wake-up sequence is Bit 5 = RIE Receiver interrupt enable. recognized. This bit is set and cleared by software. 0: Receiver in Active mode 0: Interrupt is inhibited 1: Receiver in Mute mode 1: An SCI interrupt is generated whenever OR=1 Note: Before selecting Mute mode (setting the or RDRF=1 in the SCISR register RWU bit), the SCI must receive some data first, otherwise it cannot function in Mute mode with Bit 4 = ILIE Idle line interrupt enable. wakeup by idle line detection. This bit is set and cleared by software. 0: Interrupt is inhibited Bit 0 = SBK Send break. 1: An SCI interrupt is generated whenever IDLE=1 This bit set is used to send break characters. It is in the SCISR register. set and cleared by software. Bit 3 = TE Transmitter enable. This bit enables the transmitter. It is set and cleared by software. 0: Transmitter is disabled 1: Transmitter is enabled 0: No break character is transmitted 1: Break characters are transmitted Note: If the SBK bit is set to “1” and then to “0”, the transmitter will send a BREAK word at the end of the current word. 101/167 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) DATA REGISTER (SCIDR) Read/Write Reset Value: Undefined Contains the Received or Transmitted data character, depending on whether it is read from or written to. 7 0 DR7 DR6 DR5 DR4 DR3 DR2 DR1 DR0 The Data register performs a double function (read and write) since it is composed of two registers, one for transmission (TDR) and one for reception (RDR). The TDR register provides the parallel interface between the internal bus and the output shift register (see Figure 1.). The RDR register provides the parallel interface between the input shift register and the internal bus (see Figure 1.). BAUD RATE REGISTER (SCIBRR) Read/Write Reset Value: 0000 0000 (00h) 7 0 SCP1 SCP0 SCT2 SCT1 SCT0 SCR2 SCR1 SCR0 Bits 7:6= SCP[1:0] First SCI Prescaler These 2 prescaling bits allow several standard clock division ranges: PR Prescaling factor SCP1 SCP0 1 0 0 3 0 1 4 1 0 13 1 1 102/167 1 Bits 5:3 = SCT[2:0] SCI Transmitter rate divisor These 3 bits, in conjunction with the SCP1 & SCP0 bits define the total division applied to the bus clock to yield the transmit rate clock in conventional Baud Rate Generator mode. TR dividing factor SCT2 SCT1 SCT0 1 0 0 0 2 0 0 1 4 0 1 0 8 0 1 1 16 1 0 0 32 1 0 1 64 1 1 0 128 1 1 1 Bits 2:0 = SCR[2:0] SCI Receiver rate divisor. These 3 bits, in conjunction with the SCP[1:0] bits define the total division applied to the bus clock to yield the receive rate clock in conventional Baud Rate Generator mode. RR Dividing factor SCR2 SCR1 SCR0 1 0 0 0 2 0 0 1 4 0 1 0 8 0 1 1 16 1 0 0 32 1 0 1 64 1 1 0 128 1 1 1 ST72324B SERIAL COMMUNICATIONS INTERFACE (Cont’d) EXTENDED RECEIVE PRESCALER DIVISION REGISTER (SCIERPR) Read/Write Reset Value: 0000 0000 (00h) Allows setting of the Extended Prescaler rate division factor for the receive circuit. 7 0 EXTENDED TRANSMIT PRESCALER DIVISION REGISTER (SCIETPR) Read/Write Reset Value:0000 0000 (00h) Allows setting of the External Prescaler rate division factor for the transmit circuit. 7 ERPR ERPR ERPR ERPR ERPR ERPR ERPR ERPR 7 6 5 4 3 2 1 0 ETPR 7 Bits 7:0 = ERPR[7:0] 8-bit Extended Receive Prescaler Register. The extended Baud Rate Generator is activated when a value different from 00h is stored in this register. Therefore the clock frequency issued from the 16 divider (see Figure 3.) is divided by the binary factor set in the SCIERPR register (in the range 1 to 255). The extended baud rate generator is not used after a reset. 0 ETPR 6 ETPR 5 ETPR 4 ETPR 3 ETPR 2 ETPR ETPR 1 0 Bits 7:0 = ETPR[7:0] 8-bit Extended Transmit Prescaler Register. The extended Baud Rate Generator is activated when a value different from 00h is stored in this register. Therefore the clock frequency issued from the 16 divider (see Figure 3.) is divided by the binary factor set in the SCIETPR register (in the range 1 to 255). The extended baud rate generator is not used after a reset. Table 21. Baudrate Selection Conditions Symbol Parameter fCPU Accuracy vs. Standard ~0.16% fTx fRx Communication frequency 8MHz ~0.79% Prescaler Conventional Mode TR (or RR)=128, PR=13 TR (or RR)= 32, PR=13 TR (or RR)= 16, PR=13 TR (or RR)= 8, PR=13 TR (or RR)= 4, PR=13 TR (or RR)= 16, PR= 3 TR (or RR)= 2, PR=13 TR (or RR)= 1, PR=13 Extended Mode ETPR (or ERPR) = 35, TR (or RR)= 1, PR=1 Standard Baud Rate Unit 300 ~300.48 1200 ~1201.92 2400 ~2403.84 4800 ~4807.69 9600 ~9615.38 10400 ~10416.67 19200 ~19230.77 38400 ~38461.54 Hz 14400 ~14285.71 103/167 1 ST72324B SERIAL COMMUNICATION INTERFACE (Cont’d) Table 22. SCI Register Map and Reset Values Address (Hex.) 0050h 0051h 0052h 0053h 0054h 0055h 0057h 104/167 1 Register Label 7 6 5 4 3 2 1 0 SCISR Reset Value SCIDR Reset Value SCIBRR Reset Value SCICR1 Reset Value SCICR2 Reset Value SCIERPR Reset Value SCIPETPR Reset Value TDRE 1 MSB x SCP1 0 R8 x TIE 0 MSB 0 MSB 0 TC 1 RDRF 0 IDLE 0 OR 0 NF 0 FE 0 x SCP0 0 T8 0 TCIE 0 x SCT2 0 SCID 0 RIE 0 x SCT1 0 M 0 ILIE 0 x SCT0 0 WAKE 0 TE 0 x SCR2 0 PCE 0 RE 0 x SCR1 0 PS 0 RWU 0 0 0 0 0 0 0 0 0 0 0 0 0 PE 0 LSB x SCR0 0 PIE 0 SBK 0 LSB 0 LSB 0 ST72324B 10.6 10-BIT A/D CONVERTER (ADC) 10.6.1 Introduction The on-chip Analog to Digital Converter (ADC) peripheral is a 10-bit, successive approximation converter with internal sample and hold circuitry. This peripheral has up to 16 multiplexed analog input channels (refer to device pin out description) that allow the peripheral to convert the analog voltage levels from up to 16 different sources. The result of the conversion is stored in a 10-bit Data Register. The A/D converter is controlled through a Control/Status Register. 10.6.2 Main Features ■ 10-bit conversion ■ Up to 16 channels with multiplexed input ■ Linear successive approximation ■ Data register (DR) which contains the results ■ Conversion complete status flag ■ On/off bit (to reduce consumption) The block diagram is shown in Figure 57. Figure 57. ADC Block Diagram fCPU DIV 4 0 DIV 2 fADC 1 EOC SPEED ADON 0 CH3 CH2 CH1 CH0 ADCCSR 4 AIN0 AIN1 ANALOG TO DIGITAL ANALOG MUX CONVERTER AINx ADCDRH D9 D8 ADCDRL D7 0 D6 0 D5 0 D4 0 D3 0 D2 0 D1 D0 105/167 1 ST72324B 10-BIT A/D CONVERTER (ADC) (Cont’d) 10.6.3 Functional Description The conversion is monotonic, meaning that the result never decreases if the analog input does not and never increases if the analog input does not. If the input voltage (VAIN) is greater than VAREF (high-level voltage reference) then the conversion result is FFh in the ADCDRH register and 03h in the ADCDRL register (without overflow indication). If the input voltage (VAIN) is lower than VSSA (lowlevel voltage reference) then the conversion result in the ADCDRH and ADCDRL registers is 00 00h. The A/D converter is linear and the digital result of the conversion is stored in the ADCDRH and ADCDRL registers. The accuracy of the conversion is described in the Electrical Characteristics Section. RAIN is the maximum recommended impedance for an analog input signal. If the impedance is too high, this will result in a loss of accuracy due to leakage and sampling not being completed in the alloted time. 10.6.3.1 A/D Converter Configuration The analog input ports must be configured as input, no pull-up, no interrupt. Refer to the «I/O ports» chapter. Using these pins as analog inputs does not affect the ability of the port to be read as a logic input. In the ADCCSR register: – Select the CS[3:0] bits to assign the analog channel to convert. 10.6.3.2 Starting the Conversion In the ADCCSR register: – Set the ADON bit to enable the A/D converter and to start the conversion. From this time on, the ADC performs a continuous conversion of the selected channel. When a conversion is complete: – The EOC bit is set by hardware. – The result is in the ADCDR registers. A read to the ADCDRH resets the EOC bit. 106/167 1 To read the 10 bits, perform the following steps: 1. Poll the EOC bit 2. Read the ADCDRL register 3. Read the ADCDRH register. This clears EOC automatically. Note: The data is not latched, so both the low and the high data register must be read before the next conversion is complete, so it is recommended to disable interrupts while reading the conversion result. To read only 8 bits, perform the following steps: 1. Poll the EOC bit 2. Read the ADCDRH register. This clears EOC automatically. 10.6.3.3 Changing the conversion channel The application can change channels during conversion. When software modifies the CH[3:0] bits in the ADCCSR register, the current conversion is stopped, the EOC bit is cleared, and the A/D converter starts converting the newly selected channel. 10.6.4 Low Power Modes Note: The A/D converter may be disabled by resetting the ADON bit. This feature allows reduced power consumption when no conversion is needed. Mode WAIT HALT Description No effect on A/D Converter A/D Converter disabled. After wakeup from Halt mode, the A/D Converter requires a stabilization time tSTAB (see Electrical Characteristics) before accurate conversions can be performed. 10.6.5 Interrupts None. ST72324B 10-BIT A/D CONVERTER (ADC) (Cont’d) 10.6.6 Register Description CONTROL/STATUS REGISTER (ADCCSR) Read/Write (Except bit 7 read only) Reset Value: 0000 0000 (00h) 7 EOC SPEED ADON Bit 3:0 = CH[3:0] Channel Selection These bits are set and cleared by software. They select the analog input to convert. 0 0 CH3 CH2 CH1 CH0 Bit 7 = EOC End of Conversion This bit is set by hardware. It is cleared by hardware when software reads the ADCDRH register or writes to any bit of the ADCCSR register. 0: Conversion is not complete 1: Conversion complete Bit 6 = SPEED ADC clock selection This bit is set and cleared by software. 0: fADC = fCPU/4 1: fADC = fCPU/2 Bit 5 = ADON A/D Converter on This bit is set and cleared by software. 0: Disable ADC and stop conversion 1: Enable ADC and start conversion Bit 4 = Reserved. Must be kept cleared. Channel Pin* CH3 CH2 CH1 CH0 AIN0 AIN1 AIN2 AIN3 AIN4 AIN5 AIN6 AIN7 AIN8 AIN9 AIN10 AIN11 AIN12 AIN13 AIN14 AIN15 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 *The number of channels is device dependent. Refer to the device pinout description. DATA REGISTER (ADCDRH) Read Only Reset Value: 0000 0000 (00h) 7 D9 0 D8 D7 D6 D5 D4 D3 D2 Bit 7:0 = D[9:2] MSB of Converted Analog Value DATA REGISTER (ADCDRL) Read Only Reset Value: 0000 0000 (00h) 7 0 0 0 0 0 0 0 D1 D0 Bit 7:2 = Reserved. Forced by hardware to 0. Bit 1:0 = D[1:0] LSB of Converted Analog Value 107/167 1 ST72324B 10-BIT A/D CONVERTER (Cont’d) Table 23. ADC Register Map and Reset Values Address (Hex.) Register Label 7 6 5 4 3 2 1 0 0070h ADCCSR Reset Value EOC 0 SPEED 0 ADON 0 0 CH3 0 CH2 0 CH1 0 CH0 0 0071h ADCDRH Reset Value D9 0 D8 0 D7 0 D6 0 D5 0 D4 0 D3 0 D2 0 0072h ADCDRL Reset Value 0 0 0 0 0 0 D1 0 D0 0 108/167 1 ST72324B 11 INSTRUCTION SET 11.1 CPU ADDRESSING MODES The CPU features 17 different addressing modes which can be classified in 7 main groups: Addressing Mode Example Inherent nop Immediate ld A,#$55 Direct ld A,$55 Indexed ld A,($55,X) Indirect ld A,([$55],X) Relative jrne loop Bit operation bset byte,#5 The CPU Instruction set is designed to minimize the number of bytes required per instruction: To do so, most of the addressing modes may be subdivided in two sub-modes called long and short: – Long addressing mode is more powerful because it can use the full 64 Kbyte address space, however it uses more bytes and more CPU cycles. – Short addressing mode is less powerful because it can generally only access page zero (0000h 00FFh range), but the instruction size is more compact, and faster. All memory to memory instructions use short addressing modes only (CLR, CPL, NEG, BSET, BRES, BTJT, BTJF, INC, DEC, RLC, RRC, SLL, SRL, SRA, SWAP) The ST7 Assembler optimizes the use of long and short addressing modes. Table 24. CPU Addressing Mode Overview Mode Syntax Destination Pointer Address (Hex.) Pointer Size (Hex.) Length (Bytes) Inherent nop +0 Immediate ld A,#$55 +1 Short Direct ld A,$10 00..FF +1 Long Direct ld A,$1000 0000..FFFF +2 No Offset Direct Indexed ld A,(X) 00..FF +0 Short Direct Indexed ld A,($10,X) 00..1FE +1 Long Direct Indexed ld A,($1000,X) 0000..FFFF +2 Short Indirect ld A,[$10] 00..FF 00..FF byte +2 Long Indirect ld A,[$10.w] 0000..FFFF 00..FF word +2 Short Indirect Indexed ld A,([$10],X) 00..1FE 00..FF byte +2 Long Indirect Indexed ld A,([$10.w],X) 0000..FFFF 00..FF word +2 Relative Direct jrne loop PC+/-127 Relative Indirect jrne [$10] PC+/-127 Bit Direct bset $10,#7 00..FF Bit Indirect bset [$10],#7 00..FF Bit Direct Relative btjt $10,#7,skip 00..FF Bit Indirect Relative btjt [$10],#7,skip 00..FF +1 00..FF byte +2 +1 00..FF byte +2 +2 00..FF byte +3 109/167 1 ST72324B INSTRUCTION SET OVERVIEW (Cont’d) 11.1.1 Inherent All Inherent instructions consist of a single byte. The opcode fully specifies all the required information for the CPU to process the operation. Inherent Instruction Function NOP No operation TRAP S/W Interrupt WFI Wait For Interrupt (Low Power Mode) HALT Halt Oscillator (Lowest Power Mode) RET Sub-routine Return IRET Interrupt Sub-routine Return SIM Set Interrupt Mask (level 3) RIM Reset Interrupt Mask (level 0) SCF Set Carry Flag RCF Reset Carry Flag RSP Reset Stack Pointer LD Load CLR Clear PUSH/POP Push/Pop to/from the stack INC/DEC Increment/Decrement TNZ Test Negative or Zero CPL, NEG 1 or 2 Complement MUL Byte Multiplication SLL, SRL, SRA, RLC, RRC Shift and Rotate Operations SWAP Swap Nibbles 11.1.2 Immediate Immediate instructions have two bytes, the first byte contains the opcode, the second byte contains the operand value. Immediate Instruction LD CP Compare BCP Bit Compare AND, OR, XOR Logical Operations ADC, ADD, SUB, SBC Arithmetic Operations 110/167 1 Function Load 11.1.3 Direct In Direct instructions, the operands are referenced by their memory address. The direct addressing mode consists of two submodes: Direct (short) The address is a byte, thus requires only one byte after the opcode, but only allows 00 - FF addressing space. Direct (long) The address is a word, thus allowing 64 Kbyte addressing space, but requires 2 bytes after the opcode. 11.1.4 Indexed (No Offset, Short, Long) In this mode, the operand is referenced by its memory address, which is defined by the unsigned addition of an index register (X or Y) with an offset. The indirect addressing mode consists of three sub-modes: Indexed (No Offset) There is no offset, (no extra byte after the opcode), and allows 00 - FF addressing space. Indexed (Short) The offset is a byte, thus requires only one byte after the opcode and allows 00 - 1FE addressing space. Indexed (long) The offset is a word, thus allowing 64 Kbyte addressing space and requires 2 bytes after the opcode. 11.1.5 Indirect (Short, Long) The required data byte to do the operation is found by its memory address, located in memory (pointer). The pointer address follows the opcode. The indirect addressing mode consists of two sub-modes: Indirect (short) The pointer address is a byte, the pointer size is a byte, thus allowing 00 - FF addressing space, and requires 1 byte after the opcode. Indirect (long) The pointer address is a byte, the pointer size is a word, thus allowing 64 Kbyte addressing space, and requires 1 byte after the opcode. ST72324B INSTRUCTION SET OVERVIEW (Cont’d) 11.1.6 Indirect Indexed (Short, Long) This is a combination of indirect and short indexed addressing modes. The operand is referenced by its memory address, which is defined by the unsigned addition of an index register value (X or Y) with a pointer value located in memory. The pointer address follows the opcode. The indirect indexed addressing mode consists of two sub-modes: Indirect Indexed (Short) The pointer address is a byte, the pointer size is a byte, thus allowing 00 - 1FE addressing space, and requires 1 byte after the opcode. Indirect Indexed (Long) The pointer address is a byte, the pointer size is a word, thus allowing 64 Kbyte addressing space, and requires 1 byte after the opcode. Table 25. Instructions Supporting Direct, Indexed, Indirect and Indirect Indexed Addressing Modes Long and Short Instructions LD Available Relative Direct/Indirect Instructions Function JRxx Conditional Jump CALLR Call Relative The relative addressing mode consists of two submodes: Relative (Direct) The offset is following the opcode. Relative (Indirect) The offset is defined in memory, which address follows the opcode. Function Load CP Compare AND, OR, XOR Logical Operations ADC, ADD, SUB, SBC Arithmetic Additions/Substractions operations BCP Bit Compare Short Instructions Only CLR 11.1.7 Relative mode (Direct, Indirect) This addressing mode is used to modify the PC register value, by adding an 8-bit signed offset to it. Function Clear INC, DEC Increment/Decrement TNZ Test Negative or Zero CPL, NEG 1 or 2 Complement BSET, BRES Bit Operations BTJT, BTJF Bit Test and Jump Operations SLL, SRL, SRA, RLC, RRC Shift and Rotate Operations SWAP Swap Nibbles CALL, JP Call or Jump subroutine 111/167 1 ST72324B INSTRUCTION SET OVERVIEW (Cont’d) 11.2 INSTRUCTION GROUPS The ST7 family devices use an Instruction Set consisting of 63 instructions. The instructions may Load and Transfer LD CLR Stack operation PUSH POP Increment/Decrement INC DEC Compare and Tests CP TNZ BCP Logical operations AND OR XOR CPL NEG Bit Operation BSET BRES Conditional Bit Test and Branch BTJT BTJF Arithmetic operations ADC ADD SUB SBC MUL Shift and Rotates SLL SRL SRA RLC RRC SWAP SLA Unconditional Jump or Call JRA JRT JRF JP CALL CALLR NOP Conditional Branch JRxx Interruption management TRAP WFI HALT IRET Condition Code Flag modification SIM RIM SCF RCF Using a pre-byte The instructions are described with one to four opcodes. In order to extend the number of available opcodes for an 8-bit CPU (256 opcodes), three different prebyte opcodes are defined. These prebytes modify the meaning of the instruction they precede. The whole instruction becomes: PC-2 End of previous instruction PC-1 Prebyte PC opcode PC+1 Additional word (0 to 2) according to the number of bytes required to compute the effective address 112/167 1 be subdivided into 13 main groups as illustrated in the following table: RSP RET These prebytes enable instruction in Y as well as indirect addressing modes to be implemented. They precede the opcode of the instruction in X or the instruction using direct addressing mode. The prebytes are: PDY 90 Replace an X based instruction using immediate, direct, indexed, or inherent addressing mode by a Y one. PIX 92 Replace an instruction using direct, direct bit, or direct relative addressing mode to an instruction using the corresponding indirect addressing mode. It also changes an instruction using X indexed addressing mode to an instruction using indirect X indexed addressing mode. PIY 91 Replace an instruction using X indirect indexed addressing mode by a Y one. ST72324B INSTRUCTION SET OVERVIEW (Cont’d) Mnemo Description Function/Example Dst Src I1 H I0 N Z C ADC Add with Carry A=A+M+C A M H N Z C ADD Addition A=A+M A M H N Z C AND Logical And A=A.M A M N Z BCP Bit compare A, Memory tst (A . M) A M N Z BRES Bit Reset bres Byte, #3 M BSET Bit Set bset Byte, #3 M BTJF Jump if bit is false (0) btjf Byte, #3, Jmp1 M C BTJT Jump if bit is true (1) btjt Byte, #3, Jmp1 M C CALL Call subroutine CALLR Call subroutine relative CLR Clear CP Arithmetic Compare tst(Reg - M) reg CPL One Complement A = FFH-A DEC Decrement dec Y HALT Halt IRET Interrupt routine return Pop CC, A, X, PC INC Increment inc X JP Absolute Jump jp [TBL.w] JRA Jump relative always JRT Jump relative JRF Never jump jrf * JRIH Jump if ext. INT pin = 1 (ext. INT pin high) JRIL Jump if ext. INT pin = 0 (ext. INT pin low) JRH Jump if H = 1 H=1? JRNH Jump if H = 0 H=0? JRM Jump if I1:0 = 11 I1:0 = 11 ? JRNM Jump if I1:0 <> 11 I1:0 <> 11 ? JRMI Jump if N = 1 (minus) N=1? JRPL Jump if N = 0 (plus) N=0? reg, M 0 1 N Z C reg, M N Z 1 reg, M N Z N Z N Z M 1 JREQ Jump if Z = 1 (equal) Z=1? JRNE Jump if Z = 0 (not equal) Z=0? JRC Jump if C = 1 C=1? JRNC Jump if C = 0 C=0? JRULT Jump if C = 1 Unsigned < JRUGE Jump if C = 0 Jmp if unsigned >= JRUGT Jump if (C + Z = 0) Unsigned > I1 reg, M 0 H I0 C 113/167 1 ST72324B INSTRUCTION SET OVERVIEW (Cont’d) Mnemo Description Dst Src JRULE Jump if (C + Z = 1) Unsigned <= LD Load dst <= src reg, M M, reg MUL Multiply X,A = X * A A, X, Y X, Y, A NEG Negate (2's compl) neg $10 reg, M NOP No Operation OR OR operation A=A+M A M POP Pop from the Stack pop reg reg M pop CC CC M PUSH Push onto the Stack push Y M reg, CC RCF Reset carry flag C=0 RET Subroutine Return RIM Enable Interrupts I1:0 = 10 (level 0) RLC Rotate left true C C <= A <= C reg, M N Z C RRC Rotate right true C C => A => C reg, M N Z C RSP Reset Stack Pointer S = Max allowed SBC Substract with Carry A=A-M-C N Z C SCF Set carry flag C=1 SIM Disable Interrupts I1:0 = 11 (level 3) SLA Shift left Arithmetic C <= A <= 0 reg, M N Z C SLL Shift left Logic C <= A <= 0 reg, M N Z C SRL Shift right Logic 0 => A => C reg, M 0 Z C SRA Shift right Arithmetic A7 => A => C reg, M N Z C SUB Substraction A=A-M A N Z C SWAP SWAP nibbles A7-A4 <=> A3-A0 reg, M N Z TNZ Test for Neg & Zero tnz lbl1 N Z TRAP S/W trap S/W interrupt WFI Wait for Interrupt XOR Exclusive OR N Z 114/167 1 Function/Example A = A XOR M I1 H I0 N Z N Z 0 I1 H C 0 I0 N Z N Z N Z C C 0 1 A 0 M 1 1 A 1 M M 1 1 1 0 ST72324B 12 ELECTRICAL CHARACTERISTICS 12.1 PARAMETER CONDITIONS Unless otherwise specified, all voltages are referred to VSS. 12.1.1 Minimum and Maximum values Unless otherwise specified the minimum and maximum values are guaranteed in the worst conditions of ambient temperature, supply voltage and frequencies by tests in production on 100% of the devices with an ambient temperature at TA=25°C and TA=TAmax (given by the selected temperature range). Data based on characterization results, design simulation and/or technology characteristics are indicated in the table footnotes and are not tested in production. Based on characterization, the minimum and maximum values refer to sample tests and represent the mean value plus or minus three times the standard deviation (mean±3Σ). 12.1.2 Typical values Unless otherwise specified, typical data are based on TA=25°C, VDD=5V. They are given only as design guidelines and are not tested. 12.1.3 Typical curves Unless otherwise specified, all typical curves are given only as design guidelines and are not tested. 12.1.4 Loading capacitor The loading conditions used for pin parameter measurement are shown in Figure 58. 12.1.5 Pin input voltage The input voltage measurement on a pin of the device is described in Figure 59. Figure 59. Pin input voltage ST7 PIN VIN Figure 58. Pin loading conditions ST7 PIN CL 115/167 1 ST72324B 12.2 ABSOLUTE MAXIMUM RATINGS Stresses above those listed as “absolute maximum ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device under these condi12.2.1 Voltage Characteristics Symbol tions is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. Ratings Maximum value VDD - VSS Supply voltage 6.5 VPP - VSS Programming Voltage 13 VIN 1) & 2) Input Voltage on true open drain pin VSS-0.3 to 6.5 |VSSA - VSSx| V VSS-0.3 to VDD+0.3 Input voltage on any other pin |∆VDDx| and |∆VSSx| Unit Variations between different digital power pins 50 Variations between digital and analog ground pins 50 VESD(HBM) Electro-static discharge voltage (Human Body Model) VESD(MM) Electro-static discharge voltage (Machine Model) mV see Section 12.8.3 on page 132 12.2.2 Current Characteristics Symbol Ratings Maximum value IVDD Total current into VDD power lines (source) 3) 32-pin devices 75 44-pin devices 150 IVSS Total current out of VSS ground lines (sink) 3) 32-pin devices 75 44-pin devices 150 Output current sunk by any standard I/O and control pin 25 IIO Output current sunk by any high sink I/O pin Output current source by any I/Os and control pin IINJ(PIN) 2) & 4) ΣIINJ(PIN) 2) Unit mA mA 50 - 25 Injected current on VPP pin ±5 Injected current on RESET pin ±5 Injected current on OSC1 and OSC2 pins ±5 Injected current on Flash device pin PB0 +5 Injected current on any other pin 5) & 6) ±5 Total injected current (sum of all I/O and control pins) 5) ± 25 mA Notes: 1. Directly connecting the RESET and I/O pins to VDD or VSS could damage the device if an unintentional internal reset is generated or an unexpected change of the I/O configuration occurs (for example, due to a corrupted program counter). To guarantee safe operation, this connection has to be done through a pull-up or pull-down resistor (typical: 4.7kΩ for RESET, 10kΩ for I/Os). For the same reason, unused I/O pins must not be directly tied to VDD or VSS. 2. IINJ(PIN) must never be exceeded. This is implicitly insured if VIN maximum is respected. If VIN maximum cannot be respected, the injection current must be limited externally to the IINJ(PIN) value. A positive injection is induced by VIN>VDD while a negative injection is induced by VIN<VSS. For true open-drain pads, there is no positive injection current, and the corresponding VIN maximum must always be respected 3. All power (VDD) and ground (VSS) lines must always be connected to the external supply. 4. Negative injection disturbs the analog performance of the device. See note in “ADC Accuracy” on page 146. For best reliability, it is recommended to avoid negative injection of more than 1.6mA. 5. When several inputs are submitted to a current injection, the maximum ΣIINJ(PIN) is the absolute sum of the positive and negative injected currents (instantaneous values). These results are based on characterisation with ΣIINJ(PIN) maximum current injection on four I/O port pins of the device. 6. True open drain I/O port pins do not accept positive injection. 116/167 1 ST72324B 12.2.3 Thermal Characteristics Symbol TSTG TJ Ratings Storage temperature range Value Unit -65 to +150 °C Maximum junction temperature (see Section 13.2 THERMAL CHARACTERISTICS) 12.3 OPERATING CONDITIONS 12.3.1 Operating Conditions Symbol Parameter Conditions fCPU Internal clock frequency VDD Operating voltage (except Flash Write/ Erase) Operating Voltage for Flash Write/Erase TA Ambient temperature range Min Max Unit 0 8 MHz 3.8 5.5 4.5 5.5 1 Suffix Version 0 70 5 Suffix Version -10 85 6 or A Suffix Versions -40 85 7 or B Suffix Versions -40 105 3 or C Suffix Version -40 125 VPP = 11.4 to 12.6V V °C Figure 60. fCPU Max Versus VDD fCPU [MHz] FUNCTIONALITY GUARANTEED IN THIS AREA (UNLESS OTHERWISE SPECIFIED IN THE TABLES OF PARAMETRIC DATA) 8 FUNCTIONALITY NOT GUARANTEED IN THIS AREA 6 4 2 1 0 3.5 3.8 4.0 4.5 5.5 SUPPLY VOLTAGE [V] Note: Some temperature ranges are only available with a specific package and memory size. Refer to Ordering Information. Warning: Do not connect 12V to VPP before VDD is powered on, as this may damage the device. 117/167 1 ST72324B OPERATING CONDITIONS (Cont’d) 12.4 LVD/AVD CHARACTERISTICS 12.4.1 Operating Conditions with Low Voltage Detector (LVD) Subject to general operating conditions for TA Symbol VIT+(LVD) VIT-(LVD) Vhys(LVD) Parameter Reset release threshold (VDD rise) Min Typ Max 4.0 1) 4.2 4.5 VD level = Med. in option byte2) 3.55 1) 3.75 4.01) 3.15 3.351) 4.0 4.25 1) VD level = Med. in option byte2) 3.351) 3.55 3.751) VD level = Low in option byte2) 2.81) 3.0 3.15 1) VIT+(LVD)-VIT-(LVD) 150 200 250 100 ms/V VD level = Low in option byte 2) 2.95 VD level = High in option byte Reset generation threshold (VDD fall) LVD voltage threshold hysteresis Conditions VD level = High in option byte 1) 1) 3.8 Flash devices VtPOR VDD rise time 1) tg(VDD) Filtered glitch delay on VDD 1) 8/16K ROM devices Unit V mV 20 ms/V 6µs/V ∝ ms/V 32K ROM devices Not detected by the LVD 40 ns Notes: 1. Data based on characterization results, tested in production for ROM devices only. 2. If the medium or low thresholds are selected, the detection may occur outside the specified operating voltage range. 12.4.2 Auxiliary Voltage Detector (AVD) Thresholds Subject to general operating conditions for TA Symbol Parameter Min Typ Max VD level = High in option byte Conditions 4.4 1) 4.6 4.9 VD level = Med. in option byte VD level = Low in option byte 3.95 1) 3.4 1) 4.15 3.6 4.41) 3.81) VD level = High in option byte 4.2 4.4 4.65 1) VD level = Med. in option byte VD level = Low in option byte 3.751) 3.21) 4.0 3.4 4.2 1) 3.6 1) Unit VIT+(AVD) 1⇒0 AVDF flag toggle threshold (VDD rise) VIT-(AVD) 0⇒1 AVDF flag toggle threshold (VDD fall) Vhys(AVD) AVD voltage threshold hysteresis VIT+(AVD)-VIT-(AVD) 200 mV ∆VIT- Voltage drop between AVD flag set and LVD reset activated VIT-(AVD)-VIT-(LVD) 450 mV 1. Data based on characterization results, tested in production for ROM devices only. 118/167 1 V ST72324B 12.5 SUPPLY CURRENT CHARACTERISTICS The following current consumption specified for the ST7 functional operating modes over temperature range does not take into account the clock source current consumption. To get the total device consumption, the two current values must be added (except for HALT mode for which the clock is stopped). 12.5.1 ROM CURRENT CONSUMPTION Symbol Parameter Supply current in RUN mode Conditions 2) fOSC=2MHz, fCPU=1MHz fOSC=4MHz, fCPU=2MHz fOSC=8MHz, fCPU=4MHz fOSC=16MHz, fCPU=8MHz fOSC=2MHz, fCPU=62.5kHz Supply current in SLOW mode fOSC=4MHz, fCPU=125kHz 2) fOSC=8MHz, fCPU=250kHz fOSC=16MHz, fCPU=500kHz IDD Supply current in WAIT mode 2) fOSC=2MHz, fCPU=1MHz fOSC=4MHz, fCPU=2MHz fOSC=8MHz, fCPU=4MHz fOSC=16MHz, fCPU=8MHz fOSC=2MHz, fCPU=62.5kHz Supply current in SLOW WAIT fOSC=4MHz, fCPU=125kHz fOSC=8MHz, fCPU=250kHz mode 2) fOSC=16MHz, fCPU=500kHz Supply current in HALT mode -40°C≤TA≤+85°C 3) -40°C≤TA≤+125°C IDD Supply current in ACTIVEHALT mode 4) fOSC=2MHz fOSC=4MHz fOSC=8MHz fOSC =16MHz 32K ROM Devices 16K/8K ROM Devices Unit Typ Max 1) Typ Max 1) 0.55 1.10 2.20 4.38 0.87 1.75 3.5 7.0 0.46 0.93 1.9 3.7 0.69 1.4 2.7 5.5 mA 53 100 194 380 87 175 350 700 30 70 150 310 60 120 250 500 µA 0.31 0.61 1.22 2.44 0.5 1.0 2.0 4.0 0.22 0.45 0.91 1.82 0.37 0.75 1.5 3 mA 36 69 133 260 63 125 250 500 20 40 90 190 40 90 180 350 µA <1 10 <1 10 <1 50 <1 50 15 28 55 107 20 38 75 200 11 22 43 85 15 30 60 150 µA Notes: 1. Data based on characterization results, tested in production at VDD max. and fCPU max. 2. Measurements are done in the following conditions: - Progam executed from RAM, CPU running with RAM access. - All I/O pins in input mode with a static value at VDD or VSS (no load) - All peripherals in reset state. - LVD disabled. - Clock input (OSC1) driven by external square wave. - In SLOW and SLOW WAIT mode, fCPU is based on fOSC divided by 32. To obtain the total current consumption of the device, add the clock source (Section 12.6.3) and the peripheral power consumption (Section 12.5.4). 3. All I/O pins in push-pull 0 mode (when applicable) with a static value at VDD or VSS (no load), LVD disabled. Data based on characterization results, tested in production at VDD max. and fCPU max. 4. Data based on characterisation results, not tested in production. All I/O pins in push-pull 0 mode (when applicable) with a static value at VDD or VSS (no load); clock input (OSC1) driven by external square wave, LVD disabled. To obtain the total current consumption of the device, add the clock source consumption (Section 12.6.3). 119/167 1 ST72324B 12.5.2 FLASH CURRENT CONSUMPTION ST72F324B Symbol Parameter Conditions Supply current in RUN mode 2) Supply current in SLOW mode IDD Supply current in WAIT mode 2) 2) IDD Supply current in ACTIVE-HALT mode 4) 16/8K Flash Unit Typ Max 1) Typ Max 1) fOSC=2MHz, fCPU=1MHz fOSC=4MHz, fCPU=2MHz fOSC=8MHz, fCPU=4MHz fOSC=16MHz, fCPU=8MHz 1.3 2.0 3.6 7.1 3.0 5.0 8.0 15.0 1 1.4 2.4 4.4 2.3 3.5 5.3 7.0 mA fOSC=2MHz, fCPU=62.5kHz fOSC=4MHz, fCPU=125kHz fOSC=8MHz, fCPU=250kHz fOSC=16MHz, fCPU=500kHz 0.6 0.7 0.8 1.1 2.7 3.0 3.6 4.0 0.48 0.53 0.63 0.80 1 1.1 1.2 1.4 mA fOSC=2MHz, fCPU=1MHz fOSC=4MHz, fCPU=2MHz fOSC=8MHz, fCPU=4MHz fOSC=16MHz, fCPU=8MHz 0.8 1.2 2.0 3.5 3.0 4.0 5.0 7.0 0.6 0.9 1.3 2.3 1.8 2.2 2.6 3.6 mA 580 650 770 1050 1200 1300 1800 2000 430 470 530 660 950 1000 1050 1200 µA -40°C≤TA≤+85°C <1 10 <1 10 -40°C≤TA≤+125°C 5 50 <1 50 80 160 325 650 TBD TBD TBD TBD 60 100 180 340 fOSC=2MHz, fCPU=62.5kHz Supply current in SLOW WAIT mode fOSC=4MHz, fCPU=125kHz 2) fOSC=8MHz, fCPU=250kHz fOSC=16MHz, fCPU=500kHz Supply current in HALT mode 3) 32K Flash ST72F324B fOSC=2MHz fOSC=4MHz fOSC=8MHz fOSC =16MHz µA TBD Notes: 1. Data based on characterization results, tested in production at VDD max. and fCPU max. 2. Measurements are done in the following conditions: - Progam executed from RAM, CPU running with RAM access. The increase in consumption when executing from Flash is 50%. - All I/O pins in input mode with a static value at VDD or VSS (no load) - All peripherals in reset state. - LVD disabled. - Clock input (OSC1) driven by external square wave. - In SLOW and SLOW WAIT mode, fCPU is based on fOSC divided by 32. To obtain the total current consumption of the device, add the clock source (Section 12.6.3) and the peripheral power consumption (Section 12.5.4). 3. All I/O pins in push-pull 0 mode (when applicable) with a static value at VDD or VSS (no load), LVD disabled. Data based on characterization results, tested in production at VDD max. and fCPU max. 4. Data based on characterisation results, not tested in production. All I/O pins in push-pull 0 mode (when applicable) with a static value at VDD or VSS (no load); clock input (OSC1) driven by external square wave, LVD disabled. To obtain the total current consumption of the device, add the clock source consumption (Section 12.6.3). 120/167 1 ST72324B SUPPLY CURRENT CHARACTERISTICS (Cont’d) 12.5.3 Supply and Clock Managers The previous current consumption specified for the ST7 functional operating modes over temperature range does not take into account the clock source current consumption. To get the total device consumption, the two current values must be added (except for HALT mode). Symbol Parameter Conditions IDD(RCINT) Supply current of internal RC oscillator Typ Max Unit 625 see Section 12.6.3 on page 124 IDD(RES) Supply current of resonator oscillator 1) & 2) IDD(PLL) PLL supply current VDD= 5V 360 IDD(LVD) LVD supply current VDD= 5V 150 µA µA 300 Notes: 1. Data based on characterization results done with the external components specified in Section 12.6.3 , not tested in production. 2. As the oscillator is based on a current source, the consumption does not depend on the voltage. 121/167 1 ST72324B SUPPLY CURRENT CHARACTERISTICS (Cont’d) 12.5.4 On-Chip Peripherals TA = 25°C fCPU=4MHz. Symbol Parameter Conditions Typ IDD(TIM) 16-bit Timer supply current 1) VDD=5.0V 50 IDD(SPI) SPI supply current 2) VDD=5.0V 400 IDD(SCI) SCI supply current 3) VDD=5.0V 400 IDD(ADC) ADC supply current when converting 4) VDD=5.0V 400 Unit µA Notes: 1. Data based on a differential IDD measurement between reset configuration (timer counter running at fCPU/4) and timer counter stopped (only TIMD bit set). Data valid for one timer. 2. Data based on a differential IDD measurement between reset configuration (SPI disabled) and a permanent SPI master communication at maximum speed (data sent equal to 55h). This measurement includes the pad toggling consumption. 3. Data based on a differential IDD measurement between SCI low power state (SCID=1) and a permanent SCI data transmit sequence. 4. Data based on a differential IDD measurement between reset configuration and continuous A/D conversions. 122/167 1 ST72324B 12.6 CLOCK AND TIMING CHARACTERISTICS Subject to general operating conditions for VDD, fCPU, and TA. 12.6.1 General Timings Symbol tc(INST) tv(IT) Parameter Conditions Instruction cycle time Interrupt reaction time tv(IT) = ∆tc(INST) + 10 fCPU=8MHz 2) fCPU=8MHz Min Typ 1) Max Unit 2 3 12 tCPU 250 375 1500 ns 10 22 tCPU 1.25 2.75 µs Max Unit 12.6.2 External Clock Source Symbol Parameter Conditions Min Typ VOSC1H OSC1 input pin high level voltage VDD-1 VDD VOSC1L OSC1 input pin low level voltage VSS VSS+1 tw(OSC1H) tw(OSC1L) OSC1 high or low time 3) tr(OSC1) tf(OSC1) OSC1 rise or fall time 3) IL see Figure 61 V 5 ns 15 VSS≤VIN≤VDD OSC1 Input leakage current ±1 µA Figure 61. Typical Application with an External Clock Source 90% VOSC1H 10% VOSC1L tr(OSC1) tf(OSC1) OSC2 tw(OSC1H) tw(OSC1L) Not connected internally fOSC EXTERNAL CLOCK SOURCE OSC1 IL ST72XXX Notes: 1. Data based on typical application software. 2. Time measured between interrupt event and interrupt vector fetch. ∆tc(INST) is the number of tCPU cycles needed to finish the current instruction execution. 3. Data based on design simulation and/or technology characteristics, not tested in production. 123/167 1 ST72324B CLOCK AND TIMING CHARACTERISTICS (Cont’d) 12.6.3 Crystal and Ceramic Resonator Oscillators The ST7 internal clock can be supplied with four different Crystal/Ceramic resonator oscillators. All the information given in this paragraph are based on characterization results with specified typical external components. In the application, the resonator and the load capacitors have to be placed as 12.6.3.1 8/16K Flash and ROM devices Symbol Parameter fOSC Oscillator Frequency 1) RF Feedback resistor2) CL1 CL2 close as possible to the oscillator pins in order to minimize output distortion and start-up stabilization time. Refer to the crystal/ceramic resonator manufacturer for more details (frequency, package, accuracy...). Recommended load capacitance versus equivalent serial resistance of the crystal or ceramic resonator (RS) Symbol Min Max Unit LP: Low power oscillator MP: Medium power oscillator MS: Medium speed oscillator HS: High speed oscillator Conditions 1 >2 >4 >8 2 4 8 16 MHz 20 40 kΩ RS=200Ω RS=200Ω RS=200Ω RS=100Ω 22 22 18 15 56 46 33 33 pF Typ Max Unit 80 160 310 610 150 250 460 910 µA Parameter LP oscillator MP oscillator MS oscillator HS oscillator Conditions VIN=VSS LP oscillator MP oscillator MS oscillator HS oscillator OSC2 driving current i2 Figure 62. Typical Application with a Crystal or Ceramic Resonator (8/16K Flash and ROM devices) WHEN RESONATOR WITH INTEGRATED CAPACITORS i2 fOSC CL1 OSC1 RESONATOR CL2 RF OSC2 ST72XXX Notes: 1. The oscillator selection can be optimized in terms of supply current using an high quality resonator with small RS value. Refer to crystal/ceramic resonator manufacturer for more details. 2. Data based on characterisation results, not tested in production. 124/167 1 ST72324B 12.6.3.2 32K Flash and ROM devices Symbol Parameter fOSC Oscillator Frequency RF Feedback resistor2) CL1 CL2 Conditions Recommended load capacitance versus equivalent serial resistance of the crystal or ceramic resonator (RS)3) Symbol Min Max Unit 1) fOSC= 1 to 2 MHz fOSC= 2 to 4 MHz fOSC= 4 to 8 MHz fOSC= 8 to 16 MHz Parameter Conditions 1 16 MHz 20 40 kΩ 20 20 15 15 60 50 35 35 pF Typ Max Unit 80 160 310 610 150 250 460 910 VIN=VSS i2 fOSC= 1 to 2 MHz fOSC= 2 to 4 MHz fOSC= 4 to 8 MHz fOSC= 8 to 16 MHz OSC2 driving current µA Figure 63. Typical Application with a Crystal or Ceramic Resonator (32K Flash and ROM devices) WHEN RESONATOR WITH INTEGRATED CAPACITORS CL1 fOSC POWER DOWN LOGIC OSC1 LINEAR AMPLIFIER RESONATOR RF CL2 VDD/2 Ref FEEDBACK LOOP i2 OSC2 ST72XXX Notes: 1. The oscillator selection can be optimized in terms of supply current using an high quality resonator with small RS value. Refer to crystal/ceramic resonator manufacturer for more details. 2. Data based on characterisation results, not tested in production. The relatively low value of the RF resistor, offers a good protection against issues resulting from use in a humid environment, due to the induced leakage and the bias condition change. However, it is recommended to take this point into account if the µC is used in tough humidity conditions. 3. For CL1 and CL2 it is recommended to use high-quality ceramic capacitors in the 5-pF to 25-pF range (typ.) designed for high-frequency applications and selected to match the requirements of the crystal or resonator. CL1 and CL2, are usually the same size. The crystal manufacturer typically specifies a load capacitance which is the series combination of CL1 and CL2. PCB and MCU pin capacitance must be included when sizing CL1 and CL2 (10 pF can be used as a rough estimate of the combined pin and board capacitance). 125/167 1 ST72324B CLOCK AND TIMING CHARACTERISTICS (Cont’d) Murata Supplier fOSC Typical Ceramic Resonators (MHz) Reference2) Recommended OSCRANGE Option bit configuration 2 CSTCC2M00G56A-R0 MP Mode3) 4 CSTCR4M00G55B-R0 MS Mode 8 CSTCE8M00G52A-R0 HS Mode 16 CSTCE16M0V51A-R0 HS Mode Notes: 1. Resonator characteristics given by the ceramic resonator manufacturer. 2. SMD = [-R0: Plastic tape package (∅ =180mm), -B0: Bulk] LEAD = [-A0: Flat pack package (Radial taping Ho= 18mm), -B0: Bulk] 3. LP mode is not recommended for 2 MHz resonator because the peak to peak amplitude is too small (>0.8V) For more information on these resonators, please consult www.murata.com 126/167 1 ST72324B CLOCK CHARACTERISTICS (Cont’d) 12.6.4 RC Oscillators Symbol fOSC (RCINT) Parameter Conditions Internal RC oscillator frequency TA=25°C, VDD=5V See Figure 64 Figure 64. Typical fOSC(RCINT) vs TA Min Typ Max Unit 2 3.5 5.6 MHz Note: To reduce disturbance to the RC oscillator, it is recommended to place decoupling capacitors between VDD and VSS as shown in Figure 83 fOSC(RCINT) (MHz) 4 Vdd = 5V 3.8 Vdd = 5.5V 3.6 3.4 3.2 3 -45 0 25 70 130 TA(°C) 127/167 1 ST72324B CLOCK CHARACTERISTICS (Cont’d) 12.6.5 PLL Characteristics Symbol Parameter fOSC Conditions PLL input frequency range Instantaneous PLL jitter 1) ∆ fCPU/ fCPU Min Typ 2 fOSC = 4 MHz. 0.7 Max Unit 4 MHz 2 % Note: 1. Data characterized but not tested. The user must take the PLL jitter into account in the application (for example in serial communication or sampling of high frequency signals). The PLL jitter is a periodic effect, which is integrated over several CPU cycles. Therefore the longer the period of the application signal, the less it will be impacted by the PLL jitter. Figure 65 shows the PLL jitter integrated on application signals in the range 125kHz to 2MHz. At frequencies of less than 125KHz, the jitter is negligible. Figure 65. Integrated PLL Jitter vs signal frequency1 +/-Jitter (%) 1.2 Max 1 Typ 0.8 0.6 0.4 0.2 0 4 MHz 2 MHz 1 MHz 500 kHz 250 kHz 125 kHz Application Frequency Note 1: Measurement conditions: fCPU = 8MHz. 128/167 1 ST72324B 12.7 MEMORY CHARACTERISTICS 12.7.1 RAM and Hardware Registers Symbol VRM Parameter Data retention mode 1) Conditions HALT mode (or RESET) Min Typ Max 1.6 Unit V 12.7.2 FLASH Memory DUAL VOLTAGE HDFLASH MEMORY Symbol Parameter fCPU Operating frequency VPP IDD Programming voltage 3) Supply current4) IPP VPP current4) tVPP Internal VPP stabilization time tRET NRW TPROG TERASE Data retention Write erase cycles Programming or erasing temperature range Conditions Read mode Write / Erase mode 4.5V ≤ VDD ≤ 5.5V Write / Erase Read (VPP=12V) Write / Erase Min 2) 0 1 11.4 Typ Max 2) 8 8 12.6 0 200 30 10 TA=85°C TA=105°C TA=125°C TA=25°C 40 25 10 100 -40 Unit MHz V mA µA mA µs years cycles 25 85 °C Notes: 1. Minimum VDD supply voltage without losing data stored in RAM (in HALT mode or under RESET) or in hardware registers (only in HALT mode). Not tested in production. 2. Data based on characterization results, not tested in production. 3. VPP must be applied only during the programming or erasing operation and not permanently for reliability reasons. 4. Data based on simulation results, not tested in production. 129/167 1 ST72324B 12.8 EMC CHARACTERISTICS Susceptibility tests are performed on a sample basis during product characterization. 12.8.1 Functional EMS (Electro Magnetic Susceptibility) Based on a simple running application on the product (toggling 2 LEDs through I/O ports), the product is stressed by two electro magnetic events until a failure occurs (indicated by the LEDs). ■ ESD: Electro-Static Discharge (positive and negative) is applied on all pins of the device until a functional disturbance occurs. This test conforms with the IEC 1000-4-2 standard. ■ FTB: A Burst of Fast Transient voltage (positive and negative) is applied to VDD and VSS through a 100pF capacitor, until a functional disturbance occurs. This test conforms with the IEC 1000-44 standard. A device reset allows normal operations to be resumed. The test results are given in the table below based on the EMS levels and classes defined in application note AN1709. 12.8.1.1 Designing hardened software to avoid noise problems EMC characterization and optimization are performed at component level with a typical application environment and simplified MCU software. It Symbol Parameter should be noted that good EMC performance is highly dependent on the user application and the software in particular. Therefore it is recommended that the user applies EMC software optimization and prequalification tests in relation with the EMC level requested for his application. Software recommendations: The software flowchart must include the management of runaway conditions such as: – Corrupted program counter – Unexpected reset – Critical Data corruption (control registers...) Prequalification trials: Most of the common failures (unexpected reset and program counter corruption) can be reproduced by manually forcing a low state on the RESET pin or the Oscillator pins for 1 second. To complete these trials, ESD stress can be applied directly on the device, over the range of specification values. When unexpected behaviour is detected, the software can be hardened to prevent unrecoverable errors occurring (see application note AN1015) . Conditions 32K Flash or ROM device, VDD=5V, TA=+25°C, fOSC=8MHz conforms to IEC 1000-4-2 VFESD Voltage limits to be applied on any I/O pin to induce a 8 or 16K ROM device, VDD=5V, TA=+25°C, functional disturbance fOSC=8MHz conforms to IEC 1000-4-2 8 or 16K Flash device, VDD=5V, TA=+25°C, fOSC=8MHz conforms to IEC 1000-4-2 VFFTB 130/167 1 Fast transient voltage burst limits to be applied V =5V, TA=+25°C, fOSC=8MHz through 100pF on VDD and VDD pins to induce a func- DD conforms to IEC 1000-4-4 tional disturbance Level/ Class 3B 4A 4B 4A ST72324B EMC CHARACTERISTICS (Cont’d) 12.8.2 Electro Magnetic Interference (EMI) Based on a simple application running on the product (toggling 2 LEDs through the I/O ports), the product is monitored in terms of emission. This emission test is in line with the norm SAE J 1752/ 3 which specifies the board and the loading of each pin. Symbol Parameter Conditions Device/ Package2) 8/16K Flash/ TQFP44 32K Flash/TQFP44 SEMI 1) Peak level VDD=5V, TA=+25°C conforming to SAE J 1752/3 32K ROM/TQFP44 8/16K ROM/ TQFP44 Monitored Frequency Band Max vs. [fOSC/fCPU] 8/4MHz 16/8MHz 0.1MHz to 30MHz 12 18 30MHz to 130MHz 19 25 130MHz to 1GHz 15 22 SAE EMI Level 3 3.5 0.1MHz to 30MHz 13 14 30MHz to 130MHz 20 25 130MHz to 1GHz 16 21 SAE EMI Level 3.0 3.5 0.1MHz to 30MHz 16 21 30MHz to 130MHz 24 29 130MHz to 1GHz 14 21 SAE EMI Level 3.0 3.5 0.1MHz to 30MHz 12 15 30MHz to 130MHz 23 26 130MHz to 1GHz 15 20 SAE EMI Level 3.0 3.5 Unit dBµV dBµV dBµV dBµV - Notes: 1. Not tested in production. 2. Refer to Application Note AN1709 for data on other package types. 131/167 1 ST72324B EMC CHARACTERISTICS (Cont’d) 12.8.3 Absolute Maximum Ratings (Electrical Sensitivity) Based on three different tests (ESD, LU and DLU) using specific measurement methods, the product is stressed in order to determine its performance in terms of electrical sensitivity. For more details, refer to the application note AN1181. 12.8.3.1 Electro-Static Discharge (ESD) Electro-Static Discharges (a positive then a negative pulse separated by 1 second) are applied to the pins of each sample according to each pin combination. The sample size depends on the number of supply pins in the device (3 parts*(n+1) supply pin). Two models can be simulated: Human Body Model and Machine Model. This test conforms to the JESD22-A114A/A115A standard. Absolute Maximum Ratings Symbol Ratings Conditions Maximum value 1) Unit VESD(HBM) Electro-static discharge voltage (Human Body Model) TA=+25°C 2000 VESD(MM) Electro-static discharge voltage (Machine Model) TA=+25°C 200 VESD(CDM) Electro-static discharge voltage (Charged Device Model) TA=+25°C 750 V Notes: 1. Data based on characterization results, not tested in production. 12.8.3.2 Static and Dynamic Latch-Up ■ LU: 3 complementary static tests are required on 10 parts to assess the latch-up performance. A supply overvoltage (applied to each power supply pin) and a current injection (applied to each input, output and configurable I/O pin) are performed on each sample. This test conforms to the EIA/JESD 78 IC latch-up standard. For more details, refer to the application note AN1181. ■ DLU: Electro-Static Discharges (one positive then one negative test) are applied to each pin of 3 samples when the micro is running to assess the latch-up performance in dynamic mode. Power supplies are set to the typical values, the oscillator is connected as near as possible to the pins of the micro and the component is put in reset mode. This test conforms to the IEC1000-4-2 and SAEJ1752/3 standards. For more details, refer to the application note AN1181. Electrical Sensitivities Symbol LU DLU 132/167 1 Parameter Conditions Static latch-up class TA=+25°C TA=+85°C TA=+125°C Dynamic latch-up class VDD=5.5V, fOSC=4MHz, TA=+25°C Test Specification Test Result EIA/JESD 78 Passed IEC1000-4-2 and SAEJ1752/3 Passed ST72324B 12.9 I/O PORT PIN CHARACTERISTICS 12.9.1 General Characteristics Subject to general operating conditions for VDD, fOSC, and TA unless otherwise specified. Symbol Parameter Conditions VIL Input low level voltage (standard voltage devices)1) VIH Input high level voltage 1) Vhys Schmitt trigger voltage hysteresis 2) IINJ(PIN)3) Max Unit 0.3xVDD V Injected Current on other I/O pins 0 +4 ±4 VDD=5V VSS ≤ VIN ≤ VDD Input leakage current IS Static current consumption induced by each Floating input floating input pin mode4)5) Weak pull-up equivalent resistor 6) CIO I/O pin capacitance VIN=VSS VDD=5V ±1 tr(IO)out Output low to high level rise time tw(IT)in External interrupt pulse time 7) 1) µA 200 50 120 5 1) mA ±25 Ilkg RPU V 0.7 Injected Current on Flash device pin PB0 Output high to low level fall time Typ 0.7xVDD Total injected current (sum of all I/O and ΣIINJ(PIN)3) control pins) tf(IO)out Min CL=50pF Between 10% and 90% 250 kΩ pF 25 25 1 ns tCPU Notes: 1. Data based on characterization results, not tested in production. 2. Hysteresis voltage between Schmitt trigger switching levels. Based on characterization results, not tested. 3. When the current limitation is not possible, the VIN maximum must be respected, otherwise refer to IINJ(PIN) specification. A positive injection is induced by VIN>VDD while a negative injection is induced by VIN<VSS. Refer to Section 12.2.2 on page 116 for more details. 4. Configuration not recommended, all unused pins must be kept at a fixed voltage: using the output mode of the I/O for example and leaving the I/O unconnected on the board or an external pull-up or pull-down resistor (see Figure 66). Current peak value based on design simulation and technology characteristics, not tested in production, and depending on VDD and temperature values. 5. The Schmitt trigger that is connected to every I/O port is disabled for analog inputs only when ADON bit is ON and the particular ADC channel is selected (with port configured in input floating mode)". When the ADON bit OFF static current consumption is induced. 6. The RPU pull-up equivalent resistor is based on a resistive transistor (corresponding IPU current characteristics described in Figure 67). 7. To generate an external interrupt, a minimum pulse width has to be applied on an I/O port pin configured as an external interrupt source. 133/167 1 ST72324B Figure 66. Unused I/O Pins configured as input VDD ST7XXX 10kΩ UNUSED I/O PORT UNUSED I/O PORT 10kΩ ST7XXX Note: I/O can be left unconnected if it is configured as output (0 or 1) by the software. This has the advantage of greater EMC robustness and lower cost. Figure 67. Typical IPU vs. VDD with VIN=VSS 90 Ta=1 40°C 80 Ta=9 5°C 70 Ta=2 5°C Ta=-45 °C Ipu(uA ) 60 50 40 30 20 10 0 2 134/167 1 2.5 3 3.5 4 4.5 Vdd(V) 5 5.5 6 ST72324B I/O PORT PIN CHARACTERISTICS (Cont’d) 12.9.2 Output Driving Current Subject to general operating conditions for VDD, fCPU, and TA unless otherwise specified. Symbol Parameter Conditions VOL 1) Output low level voltage for a high sink I/O pin when 4 pins are sunk at same time (see Figure 69 and Figure 71) Output high level voltage for an I/O pin when 4 pins are sourced at same time (see Figure 70 and Figure 73) VOH 2) Figure 68. Typical VOL at VDD=5V (std. ports) VDD=5V Output low level voltage for a standard I/O pin when 8 pins are sunk at same time (see Figure 68) Max IIO=+5mA 1.2 IIO=+2mA 0.5 IIO=+20mA, TA≤85°C TA>85°C 1.3 1.5 IIO=+8mA 0.6 Unit V IIO=-5mA, TA≤85°C VDD-1.4 TA>85°C VDD-1.6 VDD-0.7 IIO=-2mA Figure 70. Typical VOH at VDD=5V 5.5 1.2 5 1 Vdd-V oh (V ) at Vdd=5V Vol (V) at V dd=5V Min 0.8 0.6 Ta =14 0°C " 0.4 Ta =95 °C Ta =25 °C 0.2 Ta =-45 °C 4.5 4 3.5 V dd= 5V 1 40°C m in 3 V dd= 5v 95°C m in V dd= 5v 25°C m in 2.5 0 0 5 0.005 10 0.01 15 0.015 (mA) IIOIio(A) 2 V dd= 5v -4 5°C m in -10 -0.01 -8 -6 -4 -0.008 -0.006 -0.004 -2 -0.002 0 0 IIO (mA) Iio (A) Figure 69. Typ. VOL at VDD=5V (high-sink ports) 1 0.9 V ol(V ) at Vdd=5V 0.8 0.7 0.6 0.5 0.4 Ta= 140 °C 0.3 Ta= 95 °C 0.2 Ta= 25 °C 0.1 Ta= -45°C 0 0 10 0.01 20 0.02 IIO (mA) Iio(A) 30 0.03 Notes: 1. The IIO current sunk must always respect the absolute maximum rating specified in Section 12.2.2 and the sum of IIO (I/O ports and control pins) must not exceed IVSS. 2. The IIO current sourced must always respect the absolute maximum rating specified in Section 12.2.2 and the sum of IIO (I/O ports and control pins) must not exceed IVDD. True open drain I/O pins do not have VOH. 135/167 1 ST72324B I/O PORT PIN CHARACTERISTICS (Cont’d) Figure 71. Typical VOL vs. VDD (std. ports) 1 0.45 Ta= -4 5°C 0.9 Ta= 95°C Ta=2 5°C Ta=9 5°C 0.35 Ta= 140 °C 0.7 Vol(V) at Iio=2mA V ol(V ) at Iio=5m A 0.8 Ta=-4 5°C 0.4 Ta= 25°C 0.6 0.5 0.4 0.3 Ta=1 40°C 0.3 0.25 0.2 0.15 0.2 0.1 0.1 0.05 0 2 2.5 3 3.5 4 4.5 5 5.5 0 6 2 Vdd(V ) 2.5 3 3.5 4 4.5 5 5.5 6 Vdd(V) Figure 72. Typical VOL vs. VDD (high-sink ports) 1 .6 0 .6 Ta = 140 °C 1 .4 0 .5 Ta =95 °C 1 .2 Ta =25 °C Ta =-45°C Vol(V ) at Iio=20m A Vol(V ) at Iio=8m A 0 .4 0 .3 0 .2 1 0 .8 0 .6 Ta= 14 0°C 0 .4 Ta=9 5°C 0 .1 Ta=2 5°C 0 .2 Ta=-45 °C 0 0 2 2.5 3 3.5 4 4.5 5 5.5 2 6 2.5 3 3.5 4 4.5 5 5.5 6 V dd(V ) V dd (V ) Figure 73. Typical VOH vs. VDD 5.5 6 Ta= -4 5°C 5 4.5 Vdd-Voh(V) at Iio=-5mA Vdd-Voh(V) at Iio=-2m A 5 4 3.5 Ta= -4 5°C 3 Ta= 25°C Ta= 140°C 4 3 2 1 Ta= 140°C 2 2 2.5 3 3.5 4 Vdd(V) 1 Ta= 95°C Ta= 95°C 2.5 136/167 Ta= 25°C 4.5 5 5.5 6 0 2 2.5 3 3.5 4 Vdd(V) 4.5 5 5.5 6 ST72324B 12.10 CONTROL PIN CHARACTERISTICS 12.10.1 Asynchronous RESET Pin Subject to general operating conditions for VDD, fCPU, and TA unless otherwise specified. Symbol Parameter Conditions VIL Input low level voltage VIH Input high level voltage 1) Vhys Schmitt trigger voltage hysteresis 2) VOL Output low level voltage 3) IIO RON Min Typ 1) Filtered glitch duration 5) V IIO=+2mA 0.2 0.5 V 2 tw(RSTL)out Generated reset pulse duration External reset pulse hold time 0.3xVDD 2.5 VDD=5V Weak pull-up equivalent resistor th(RSTL)in Unit 0.7xVDD Driving current on RESET pin tg(RSTL)in Max 4) mA VDD=5V 20 30 120 kΩ Internal reset sources 20 30 426) µs µs 2.5 200 ns Notes: 1. Data based on characterization results, not tested in production. 2. Hysteresis voltage between Schmitt trigger switching levels. 3. The IIO current sunk must always respect the absolute maximum rating specified in Section 12.2.2 and the sum of IIO (I/O ports and control pins) must not exceed IVSS. 4. To guarantee the reset of the device, a minimum pulse has to be applied to the RESET pin. All short pulses applied on the RESET pin with a duration below th(RSTL)in can be ignored. 5. The reset network (the resistor and two capacitors) protects the device against parasitic resets, especially in noisy environments. 6. Data guaranteed by design, not tested in production. 137/167 1 ST72324B CONTROL PIN CHARACTERISTICS (Cont’d) Figure 74. RESET pin protection when LVD is enabled.1)2) VDD Recommended Optional (note 2.2) ST72XXX RON EXTERNAL RESET INTERNAL RESET Filter 0.01µF 1MΩ PULSE GENERATOR WATCHDOG LVD RESET Figure 75. RESET pin protection when LVD is disabled.1) Recommended VDD VDD USER EXTERNAL RESET CIRCUIT ST72XXX VDD 0.01µF 4.7kΩ RON INTERNAL RESET Filter 0.01µF PULSE GENERATOR WATCHDOG Required Note 1: 1.1 The reset network protects the device against parasitic resets. 1.2 The output of the external reset circuit must have an open-drain output to drive the ST7 reset pad. Otherwise the device can be damaged when the ST7 generates an internal reset (LVD or watchdog). 1.3 Whatever the reset source is (internal or external), the user must ensure that the level on the RESET pin can go below the VIL max. level specified in Section 12.10.1 . Otherwise the reset will not be taken into account internally. 1.4 Because the reset circuit is designed to allow the internal RESET to be output in the RESET pin, the user must ensure that the current sunk on the RESET pin (by an external pull-up for example) is less than the absolute maximum value specified for IINJ(RESET) in Section 12.2.2 on page 116. Note 2: 2.1 When the LVD is enabled, it is mandatory not to connect a pull-up resistor. A 10nF pull-down capacitor is recommended to filter noise on the reset line. 2.2. In case a capacitive power supply is used, it is recommended to connect a1MW pull-down resistor to the RESET pin to discharge any residual voltage induced by this capacitive power supply (this will add 5µA to the power consumption of the MCU). 2.3. Tips when using the LVD: – 1. Check that all recommendations related to reset circuit have been applied (see notes above) – 2. Check that the power supply is properly decoupled (100nF + 10µF close to the MCU). Refer to AN1709. If this cannot be done, it is recommended to put a 100nF + 1MW pull-down on the RESET pin. – 3. The capacitors connected on the RESET pin and also the power supply are key to avoiding any start-up marginality. In most cases, steps 1 and 2 above are sufficient for a robust solution. Otherwise: replace 10nF pull-down on the RESET pin with a 5µF to 20µF capacitor.” 138/167 1 ST72324B CONTROL PIN CHARACTERISTICS (Cont’d) 12.10.2 ICCSEL/VPP Pin Subject to general operating conditions for VDD, fCPU, and TA unless otherwise specified. Symbol Parameter Conditions Min Max VSS 0.2 ROM versions VSS 0.3xVDD VIL Input low level voltage 1) FLASH versions VIH Input high level voltage 1) FLASH versions VDD-0.1 12.6 ROM versions 0.7xVDD VDD IL Input leakage current VIN=VSS ±1 Unit V µA Figure 76. Two typical Applications with ICCSEL/VPP Pin 2) ICCSEL/VPP ST72XXX VPP PROGRAMMING TOOL 10kΩ ST72XXX Notes: 1. Data based on design simulation and/or technology characteristics, not tested in production. 2. When ICC mode is not required by the application ICCSEL/VPP pin must be tied to VSS. 139/167 1 ST72324B 12.11 TIMER PERIPHERAL CHARACTERISTICS Subject to general operating conditions for VDD, fOSC, and TA unless otherwise specified. Refer to I/O port characteristics for more details on the input/output alternate function characteristics (output compare, input capture, external clock, PWM output...). Data based on design simulation and/or characterisation results, not tested in production. 12.11.1 16-Bit Timer Symbol Parameter Conditions tw(ICAP)in Input capture pulse time tres(PWM) PWM resolution time Typ Max Unit 1 tCPU 2 tCPU 250 ns fEXT Timer external clock frequency 0 fCPU/4 MHz fPWM PWM repetition rate 0 fCPU/4 MHz 16 bit ResPWM PWM resolution 140/167 1 fCPU=8MHz Min ST72324B 12.12 COMMUNICATION INTERFACE CHARACTERISTICS 12.12.1 SPI - Serial Peripheral Interface Subject to general operating conditions for VDD, fCPU, and TA unless otherwise specified. Data based on design simulation and/or characterisation results, not tested in production. When no communication is on-going the data output line of the SPI (MOSI in master mode, MISO in slave mode) has its alternate function capability released. In this case, the pin status depends on the I/O port configuration. Refer to I/O port characteristics for more details on the input/output alternate function characteristics (SS, SCK, MOSI, MISO). Symbol Parameter Conditions Master fSCK 1/tc(SCK) fCPU=8MHz SPI clock frequency Slave fCPU=8MHz Min Max fCPU/128 0.0625 fCPU/4 2 0 fCPU/2 4 tr(SCK) tf(SCK) SPI clock rise and fall time tsu(SS) SS setup time Slave 120 th(SS) SS hold time Slave 120 SCK high and low time Master Slave 100 90 tsu(MI) tsu(SI) Data input setup time Master Slave 100 100 th(MI) th(SI) Data input hold time Master Slave 100 100 ta(SO) Data output access time Slave 0 tdis(SO) Data output disable time Slave tw(SCKH) tw(SCKL) tv(SO) Data output valid time th(SO) Data output hold time tv(MO) Data output valid time th(MO) Data output hold time Unit MHz see I/O port pin description ns 120 240 90 Slave (after enable edge) 0 Master (before capture edge) 0.25 tCPU 0.25 Figure 77. SPI Slave Timing Diagram with CPHA=0 1) SS INPUT SCK INPUT tsu(SS) tc(SCK) th(SS) CPHA=0 CPOL=0 CPHA=0 CPOL=1 ta(SO) MISO OUTPUT tw(SCKH) tw(SCKL) MSB OUT see note 2 tsu(SI) MOSI INPUT tv(SO) th(SO) BIT6 OUT tdis(SO) tr(SCK) tf(SCK) LSB OUT see note 2 th(SI) MSB IN BIT1 IN LSB IN Notes: 1. Measurement points are done at CMOS levels: 0.3xVDD and 0.7xVDD. 141/167 1 ST72324B COMMUNICATION INTERFACE CHARACTERISTICS (Cont’d) Figure 78. SPI Slave Timing Diagram with CPHA=11) SS INPUT SCK INPUT tsu(SS) tc(SCK) th(SS) CPHA=1 CPOL=0 CPHA=1 CPOL=1 tw(SCKH) tw(SCKL) ta(SO) MISO OUTPUT see note 2 tv(SO) th(SO) MSB OUT HZ tsu(SI) BIT6 OUT LSB OUT see note 2 th(SI) MSB IN MOSI INPUT tdis(SO) tr(SCK) tf(SCK) BIT1 IN LSB IN Figure 79. SPI Master Timing Diagram 1) SS INPUT tc(SCK) SCK INPUT CPHA=0 CPOL=0 CPHA=0 CPOL=1 CPHA=1 CPOL=0 CPHA=1 CPOL=1 tw(SCKH) tw(SCKL) tsu(MI) MISO INPUT MOSI OUTPUT th(MI) MSB IN tv(MO) see note 2 tr(SCK) tf(SCK) BIT6 IN LSB IN th(MO) MSB OUT BIT6 OUT LSB OUT see note 2 Notes: 1. Measurement points are done at CMOS levels: 0.3xVDD and 0.7xVDD. 2. When no communication is on-going the data output line of the SPI (MOSI in master mode, MISO in slave mode) has its alternate function capability released. In this case, the pin status depends of the I/O port configuration. 142/167 1 ST72324B 12.13 10-BIT ADC CHARACTERISTICS Subject to general operating conditions for VDD, fCPU, and TA unless otherwise specified. Symbol fADC VAREF VAIN Parameter Conditions ADC clock frequency 0.7*VDD ≤VAREF ≤VDD Analog reference voltage Conversion voltage range 1) Min Max Unit 0.4 Typ 2 MHz 3.8 VDD VSSA VAREF Positive input leakage current for analog -40°C≤TA≤+85°C input +85°C≤TA≤+125°C Ilkg Negative input leakage current on robust analog pins RAIN External input impedance CAIN External capacitor on analog input fAIN Variation freq. of analog input signal VIN<VSS, | IIN |< 400µA on adjacent robust analog pin 5 V ±250 nA ±1 µA 6 µA see Figure 80 and Figure 812)3)4) kΩ pF Hz CADC Internal sample and hold capacitor 12 pF tADC Conversion time (Sample+Hold) fCPU=8MHz, SPEED=0 fADC=2MHz 7.5 µs tADC - No of sample capacitor loading cycles - No. of Hold conversion cycles 4 11 1/fADC Notes: 1. Any added external serial resistor will downgrade the ADC accuracy (especially for resistance greater than 10kΩ). Data based on characterization results, not tested in production. 143/167 1 ST72324B ADC CHARACTERISTICS (Cont’d) Figure 80. RAIN max. vs fADC with CAIN=0pF1) Figure 81. Recommended CAIN & RAIN values.2) 45 1000 Cain 10 nF 2 MHz 35 30 1 MHz 25 Cain 22 nF 100 Max. R AIN (Kohm) Max. R AIN (Kohm) 40 20 15 10 Cain 47 nF 10 1 5 0 0.1 0 10 30 70 0.01 0.1 CPARASITIC (pF) 1 10 fAIN(KHz) Figure 82. Typical A/D Converter Application VDD RAIN AINx ST72XXX VT 0.6V 2kΩ(max) VAIN CAIN VT 0.6V IL ±1µA 10-Bit A/D Conversion CADC 12pF Notes: 1. CPARASITIC represents the capacitance of the PCB (dependent on soldering and PCB layout quality) plus the pad capacitance (3pF). A high CPARASITIC value will downgrade conversion accuracy. To remedy this, fADC should be reduced. 2. This graph shows that depending on the input signal variation (fAIN), CAIN can be increased for stabilization time and decreased to allow the use of a larger serial resistor (RAIN). 144/167 1 ST72324B ADC CHARACTERISTICS (Cont’d) 12.13.1 Analog Power Supply and Reference Pins Depending on the MCU pin count, the package may feature separate VAREF and VSSA analog power supply pins. These pins supply power to the A/D converter cell and function as the high and low reference voltages for the conversion. In some packages, VAREF and VSSA pins are not available (refer to Section 2 on page 8). In this case the analog supply and reference pads are internally bonded to the VDD and VSS pins. Separation of the digital and analog power pins allow board designers to improve A/D performance. Conversion accuracy can be impacted by voltage drops and noise in the event of heavily loaded or badly decoupled power supply lines (see Section 12.13.2 General PCB Design Guidelines). 12.13.2 General PCB Design Guidelines To obtain best results, some general design and layout rules should be followed when designing the application PCB to shield the noise-sensitive, analog physical interface from noise-generating CMOS logic signals. – Use separate digital and analog planes. The analog ground plane should be connected to the digital ground plane via a single point on the PCB. – Filter power to the analog power planes. It is recommended to connect capacitors, with good high frequency characteristics, between the power and ground lines, placing 0.1µF and optionally, if needed 10pF capacitors as close as possible to the ST7 power supply pins and a 1 to 10µF capacitor close to the power source (see Figure 83). – The analog and digital power supplies should be connected in a star nework. Do not use a resistor, as VAREF is used as a reference voltage by the A/D converter and any resistance would cause a voltage drop and a loss of accuracy. – Properly place components and route the signal traces on the PCB to shield the analog inputs. Analog signals paths should run over the analog ground plane and be as short as possible. Isolate analog signals from digital signals that may switch while the analog inputs are being sampled by the A/D converter. Do not toggle digital outputs on the same I/O port as the A/D input being converted. Figure 83. Power Supply Filtering ST72XXX 1 to 10µF 0.1µF ST7 DIGITAL NOISE FILTERING VSS VDD VDD POWER SUPPLY SOURCE 0.1µF EXTERNAL NOISE FILTERING VAREF VSSA 145/167 1 ST72324B 10-BIT ADC CHARACTERISTICS (Cont’d) 12.13.3 ADC Accuracy Conditions: VDD=5V 1) Symbol Parameter |ET| Total unadjusted error |EO| Offset error 1) |EG| Gain Error Conditions 1) 1) |ED| Differential linearity error 1) CPU in run mode @ fADC 2 MHz. |EL| Integral linearity error 1) CPU in run mode @ fADC 2 MHz. Typ Max2) 3 4 2 3 0.5 3 1 2 1 2 Unit LSB Notes: 1. ADC Accuracy vs. Negative Injection Current: Injecting negative current may reduce the accuracy of the conversion being performed on another analog input. The effect of negative injection current on robust pins is specified in Section 12.13. Any positive injection current within the limits specified for IINJ(PIN) and ΣIINJ(PIN) in Section 12.9 does not affect the ADC accuracy. 2. Data based on characterization results, monitored in production to guarantee 99.73% within ± max value from -40°C to 125°C ( ± 3σ distribution limits). Figure 84. ADC Accuracy Characteristics Digital Result ADCDR EG 1023 1022 1LSB 1021 IDEAL V –V AREF SSA = -------------------------------------------- 1024 (2) ET ET=Total Unadjusted Error: maximum deviation between the actual and the ideal transfer curves. EO=Offset Error: deviation between the first actual transition and the first ideal one. EG=Gain Error: deviation between the last ideal transition and the last actual one. ED=Differential Linearity Error: maximum deviation between actual steps and the ideal one. EL=Integral Linearity Error: maximum deviation between any actual transition and the end point correlation line. (3) 7 (1) 6 5 EO 4 EL 3 ED 2 1 LSBIDEAL 1 0 1 VSSA 146/167 1 (1) Example of an actual transfer curve (2) The ideal transfer curve (3) End point correlation line Vin (LSBIDEAL) 2 3 4 5 6 7 1021 1022 1023 1024 VAREF ST72324B 13 PACKAGE CHARACTERISTICS 13.1 PACKAGE MECHANICAL DATA Figure 85. 44-Pin Thin Quad Flat Package Dim. A A2 D D1 b e c L1 inches Max Min Typ Max 1.60 0.063 0.15 0.002 0.006 A1 0.05 A2 1.35 1.40 1.45 0.053 0.055 0.057 b 0.30 0.37 0.45 0.012 0.015 0.018 C 0.09 0.20 0.004 0.000 0.008 D 12.00 0.472 D1 10.00 0.394 E 12.00 0.472 E1 10.00 0.394 e 0.80 0.031 θ 0° 3.5° L 0.45 0.60 L1 L Typ A A1 E1 E mm Min 7° 0° 1.00 h 3.5° 7° 0.75 0.018 0.024 0.030 0.039 Number of Pins N 44 Figure 86. 32-Pin Thin Quad Flat Package Dim. mm Min Typ inches Max Min Typ Max D A A D1 A2 A1 0.05 A2 1.35 1.40 1.45 0.053 0.055 0.057 b 0.30 0.37 0.45 0.012 0.015 0.018 C 0.09 A1 e E1 E b c L1 L h 1.60 0.063 0.15 0.002 0.006 0.20 0.004 0.008 D 9.00 0.354 D1 7.00 0.276 E 9.00 0.354 E1 7.00 0.276 e 0.80 0.031 θ 0° 3.5° L 0.45 0.60 L1 7° 0° 3.5° 7° 0.75 0.018 0.024 0.030 1.00 0.039 Number of Pins N 32 147/167 1 ST72324B PACKAGE MECHANICAL DATA (Cont’d) Figure 87. 42-Pin Plastic Dual In-Line Package, Shrink 600-mil Width - Dim. E mm Min Typ A A A2 A1 b2 L c e b E1 eA eB D E 0.015 GAGE PLANE eC inches Max Min Typ 5.08 Max 0.200 A1 0.51 0.020 A2 3.05 3.81 4.57 0.120 0.150 0.180 b 0.38 0.46 0.56 0.015 0.018 0.022 b2 0.89 1.02 1.14 0.035 0.040 0.045 c 0.23 0.25 0.38 0.009 0.010 0.015 D 36.58 36.83 37.08 1.440 1.450 1.460 E 15.24 E1 12.70 13.72 14.48 0.500 0.540 0.570 16.00 0.600 e 1.78 eA 15.24 0.630 0.070 0.600 eB 18.54 0.730 eC 1.52 0.000 0.060 eB L 2.54 3.30 3.56 0.100 0.130 0.140 Number of Pins N 42 Figure 88. 32-Pin Plastic Dual In-Line Package, Shrink 400-mil Width Dim. E A2 A A1 L C b b2 D e E1 eA eB mm inches Min Typ Max A 3.56 3.76 5.08 0.140 0.148 0.200 A1 0.51 A2 3.05 3.56 4.57 0.120 0.140 0.180 eC Min Typ 0.020 b 0.36 0.46 0.58 0.014 0.018 0.023 b1 0.76 1.02 1.40 0.030 0.040 0.055 C 0.20 0.25 D 27.43 E 9.91 10.41 11.05 0.390 0.410 0.435 E1 7.62 0.36 0.008 0.010 0.014 28.45 1.080 1.100 1.120 8.89 9.40 0.300 0.350 0.370 e 1.78 0.070 eA 10.16 0.400 eB 12.70 0.500 eC 1.40 0.055 L 2.54 3.05 3.81 0.100 0.120 0.150 Number of Pins N 148/167 1 Max 32 ST72324B 13.2 THERMAL CHARACTERISTICS Symbol Ratings Value RthJA Package thermal resistance (junction to ambient) TQFP44 10x10 TQFP32 7x7 SDIP42 600mil SDIP32 200mil 52 70 55 50 Power dissipation 1) 500 mW 150 °C PD TJmax Maximum junction temperature 2) Unit °C/W Notes: 1. The maximum chip-junction temperature is based on technology characteristics. 2. The maximum power dissipation is obtained from the formula PD = (TJ -TA) / RthJA. The power dissipation of an application can be defined by the user with the formula: PD=PINT+PPORT where PINT is the chip internal power (IDD x VDD) and PPORT is the port power dissipation depending on the ports used in the application. 149/167 1 ST72324B 13.3 SOLDERING INFORMATION In accordance with the RoHS European directive, all STMicroelectronics packages will be converted in 2005 to lead-free technology, named ECOPACKTM (for a detailed roadmap, please refer to PCN CRP/04/744 "Lead-free Conversion Program - Compliance with RoHS", issued November 18th, 2004). TM ■ ECOPACK packages are qualified according to the JEDEC STD-020B compliant soldering profile. ■ Detailed information on the STMicroelectronic ECOPACKTM transition program is available on www.st.com/stonline/leadfree/, with specific technical Application notes covering the main technical aspects related to lead-free conversion (AN2033, AN2034, AN2035, AN2036). Backward and forward compatibility: The main difference between Pb and Pb-free soldering process is the temperature range. – ECOPACKTM TQFP, SDIP and SO packages are fully compatible with Lead (Pb) containing soldering process (see application note AN2034) – TQFP, SDIP and SO Pb-packages are compatible with Lead-free soldering process, nevertheless it's the customer's duty to verify that the Pbpackages maximum temperature (mentioned on the Inner box label) is compatible with their Leadfree soldering temperature. Table 26. Soldering Compatibility (wave and reflow soldering process) Package SDIP & PDIP TQFP and SO Plating material devices Sn (pure Tin) NiPdAu (Nickel-palladium-Gold) Pb solder paste Yes Yes Pb-free solder paste Yes * Yes * * Assemblers must verify that the Pb-package maximum temperature (mentioned on the Inner box label) is compatible with their Lead-free soldering process. 150/167 1 ST72324B 14 ST72324B DEVICE CONFIGURATION AND ORDERING INFORMATION Each device is available for production in user programmable versions (FLASH) as well as in factory coded versions (ROM). ST72324B devices are ROM versions. ST72P324B devices are Factory Advanced Service Technique ROM (FASTROM) versions: they are factory-programmed HDFlash devices. FLASH devices are shipped to customers with a default content (FFh), while ROM factory coded parts contain the code supplied by the customer. This implies that FLASH devices have to be configured by the customer using the Option Bytes while the ROM devices are factory-configured. 14.1 FLASH OPTION BYTES STATIC OPTION BYTE 0 STATIC OPTION BYTE 1 0 0 1 1 1 1 1 VD The option bytes allows the hardware configuration of the microcontroller to be selected. They have no address in the memory map and can be accessed only in programming mode (for example using a standard ST7 programming tool). The default content of the FLASH is fixed to FFh. To program directly the FLASH devices using ICP, FLASH devices are shipped to customers with the internal RC clock source. In masked ROM devices, the option bytes are fixed in hardware by the ROM code (see option list). OPTION BYTE 0 OPT7= WDG HALT Watchdog reset on HALT This option bit determines if a RESET is generated when entering HALT mode while the Watchdog is active. 0: No Reset generation when entering Halt mode 1: Reset generation when entering Halt mode OPT6= WDG SW Hardware or software watchdog This option bit selects the watchdog type. 0: Hardware (watchdog always enabled) 1: Software (watchdog to be enabled by software) OPT5 = Reserved, must be kept at default value. OPT4:3= VD[1:0] Voltage detection These option bits enable the voltage detection block (LVD, and AVD) with a selected threshold for OSCTYPE OSCRANGE 1 0 2 1 0 PLLOFF 1 RSTC 1 PKG1 1 0 FMP_R Default 0 Reserved Reserved 1 WDG 7 Reserved SW 0 HALT 7 1 0 1 1 1 1 Selected Low Voltage Detector VD1 VD0 LVD and AVD Off Lowest Voltage Threshold (VDD~3V) Medium Voltage Threshold (VDD~3.5V) Highest Voltage Threshold (VDD~4V) 1 1 0 0 1 0 1 0 Caution: If the medium or low thresholds are selected, the detection may occur outside the specified operating voltage range. Below 3.8V, device operation is not guaranteed. For details on the AVD and LVD threshold levels refer to Section 12.4.1 on page 118 OPT2:1 = Reserved, must be kept at default value. OPT0= FMP_R Flash memory read-out protection Read-out protection, when selected, provides a protection against Program Memory content extraction and against write access to Flash memory. Erasing the option bytes when the FMP_R option is selected causes the whole user memory to be erased first, and the device can be reprogrammed. Refer to Section 7.3.1 on page 37 and the ST7 Flash Programming Reference Manual for more details. 0: Read-out protection enabled 1: Read-out protection disabled 151/167 1 ST72324B ST72324B DEVICE CONFIGURATION AND ORDERING INFORMATION (Cont’d) OPTION BYTE 1 OPT7= PKG1 Pin package selection bit This option bit selects the package. Version Selected Package PKG1 J TQFP44 / SDIP42 1 K TQFP32 / SDIP32 0 Note: On the chip, each I/O port has 8 pads. Pads that are not bonded to external pins are in input pull-up configuration after reset. The configuration of these pads must be kept at reset state to avoid added current consumption. OPT6 = RSTC RESET clock cycle selection This option bit selects the number of CPU cycles applied during the RESET phase and when exiting HALT mode. For resonator oscillators, it is advised to select 4096 due to the long crystal stabilization time. 0: Reset phase with 4096 CPU cycles 1: Reset phase with 256 CPU cycles OPT5:4 = OSCTYPE[1:0] Oscillator Type These option bits select the ST7 main clock source type. OSCTYPE Clock Source 1 0 Resonator Oscillator 0 0 Reserved 0 1 Internal RC Oscillator 1 0 External Source 1 1 OPT3:1 = OSCRANGE[2:0] Oscillator range When the resonator oscillator type is selected, 152/167 1 these option bits select the resonator oscillator current source corresponding to the frequency range of the used resonator. Otherwise, these bits are used to select the normal operating frequency range. OSCRANGE Typ. Freq. Range 2 1 0 LP 1~2MHz 0 0 0 MP 2~4MHz 0 0 1 MS 4~8MHz 0 1 0 HS 8~16MHz 0 1 1 OPT0 = PLL OFF PLL activation This option bit activates the PLL which allows multiplication by two of the main input clock frequency. The PLL must not be used with the internal RC oscillator. The PLL is guaranteed only with an input frequency between 2 and 4MHz. 0: PLL x2 enabled 1: PLL x2 disabled CAUTION: the PLL can be enabled only if the “OSC RANGE” (OPT3:1) bits are configured to “MP - 2~4MHz”. Otherwise, the device functionality is not guaranteed. ST72324B ST72324B DEVICE CONFIGURATION AND ORDERING INFORMATION (Cont’d) 14.2 ROM DEVICE ORDERING INFORMATION AND TRANSFER OF CUSTOMER CODE ROM devices can be ordered in any combination of memory size and temperature range with the types given in Figure 89 and by completing the option list on the next page. Flash devices are available only in the types listed in Table 27 and Table 28. ROM customer code is made up of the ROM contents and the list of the selected options (if any). The ROM contents are to be sent with the S19 hexadecimal file generated by the development tool. All unused bytes must be set to FFh. Refer to application note AN1635 for information on the counter listing returned by ST after code has been transferred. The STMicroelectronics Sales Organization will be pleased to provide detailed information on contractual points. Figure 89. ROM Factory Coded Device Types DEVICE PACKAGE VERSION / XXX Code name (defined by STMicroelectronics) 1= Standard 0 to +70 °C 5= Standard -10 to +85 °C 6= Standard -40 to +85 °C 7= Standard -40 to +105 °C 3= Standard -40 to +125 °C A = Automotive -40 to +85 °C B = Automotive -40 to +105 °C C = Automotive -40 to +125 °C T= Plastic Thin Quad Flat Pack B= Plastic Dual in Line ST72324BJ6, ST72324BJ4, ST72324BJ2 ST72324BK6, ST72324BK4, ST72324BK2 153/167 1 ST72324B ST72324B DEVICE CONFIGURATION AND ORDERING INFORMATION (Cont’d) ST72324B (5V) MICROCONTROLLER OPTION LIST (Last updated December 2005) Customer: ................................... Address: ................................... ................................... Contact: ................................... Phone No: ................................... Reference/ROM Code* : . . . . . . . . . . . . . . . . . . . . . . . . . . . *The ROM code name is assigned by STMicroelectronics. ROM code must be sent in .S19 format. .Hex extension cannot be processed. Device Type/Memory Size/Package (check only one option): --------------------------------------------------------------------|| ROM DEVICE: 32K --------------------------------------------------------------------TQFP32: | [ ] ST72324BK6T DIP32: | [ ] ST72324BK6B TQFP44 : | [ ] ST72324BJ6T DIP42: | [ ] ST72324BJ6B ----------------------------------------------------------------------DIE FORM: || 32K ----------------------------------------------------------------------32-pin: | [] 44-pin: | [] Conditioning (check only one option): -----------------------------------------------------------------------Packaged Product -----------------------------------------------------------------------TQFP: [ ] Tape & Reel [ ] Tray DIP: [ ] Tube || | | | | || | | ------------------------------------16K ------------------------------------[ ] ST72324BK4T [ ] ST72324BK4B [ ] ST72324BJ4T [ ] ST72324BJ4B --------------------------------------16K --------------------------------------[] [] || | | | | || | | --------------------------------8K --------------------------------[ ] ST72324BK2T [ ] ST72324BK2B [ ] ST72324BJ2T [ ] ST72324BJ2B ---------------------------------8K ---------------------------------[] [] | ----------------------------------------------------Die Product (dice tested at 25°C only) | ----------------------------------------------------| [ ] Tape & Reel | [ ] Inked wafer | [ ] Sawn wafer on sticky foil Power Supply Range: [ ] 3.8 to 5.5V Version/Temp. Range (do not check for die product). Please refer to datasheet for specific sales conditions: ---------------------------------------------------------------------------| Automotive || Standard Temp. Range ---------------------------------------------------------------------------[] | | 0°C to +70°C [] | | -10°C to +85°C [] | [] | -40°C to +85°C [] | [] | -40°C to +105°C [] | [] | -40°C to +125°C Special Marking: [ ] No [ ] Yes "_ _ _ _ _ _ _ _ _ _ " (TQFP32 7 char., other pkg. 10 char. max) Authorized characters are letters, digits, '.', '-', '/' and spaces only. Clock Source Selection: [ ] Resonator: [ ] LP: Low power resonator (1 to 2 MHz) [ ] MP: Medium power resonator (2 to 4 MHz) [ ] MS: Medium speed resonator (4 to 8 MHz) [ ] HS: High speed resonator (8 to 16 MHz) [ ] Internal RC: [ ] External Clock PLL LVD Reset [ ] Disabled Reset Delay [ ] Disabled [ ] Enabled [ ] High threshold [ ] Med. threshold [ ] Low threshold [ ] 256 Cycles [ ] 4096 Cycles Watchdog Selection: Watchdog Reset on Halt: [ ] Software Activation [ ] Reset [ ] Hardware Activation [ ] No Reset Readout Protection: [ ] Disabled [ ] Enabled Date ................................ Signature ................................ Note: CSS option disabled (set to 1) by ST at ROM code entry. Caution: The Readout Protection binary value is inverted between ROM and FLASH products. The option byte checksum will differ between ROM and FLASH. 154/167 1 ST72324B DEVICE CONFIGURATION AND ORDERING INFORMATION (Cont’d) 14.3 FLASH DEVICE ORDERING INFORMATiON Refer to the following tables for guidance on ordering. Standard and Industrial Versions ■ For existing and new designs select the ST72F324B devices from Table 27. ■ For running production orders of earlier ST72F324 devices, refer to ordering information in the separate datasheet. Automotive applications ■ For existing and new designs in Automotive applications select the devices from Table 28. Table 27. Standard and Industrial ST72F324B Flash Order Codes Part Number Package Flash Memory (KBytes) ST72F324BK2B5 8 ST72F324BK4B5 16 ST72F324BK6B5 32 ST72F324BK2B6 SDIP32 16 ST72F324BK6B6 32 ST72F324BJ2B5 8 ST72F324BJ4B5 16 ST72F324BJ6B5 32 SDIP42 16 ST72F324BJ6B6 32 ST72F324BK2T5 32 ST72F324BK2T6 8 ST72F324BK6T6 16 TQFP32 8 ST72F324BK4T3 16 ST72F324BK6T3 32 ST72F324BJ2T5 32 ST72F324BJ2T6 8 ST72F324BJ4T6 16 TQFP44 -10°C +85°C -40°C +85°C -10°C +85°C -40°C +85°C 32 ST72F324BK2T3 ST72F324BJ6T6 -40°C +85°C 8 ST72F324BJ4B6 ST72F324BK4T6 -10°C +85°C 8 ST72F324BK4B6 ST72F324BJ2B6 Temp. Range -40°C +125°C -10°C +85°C -40°C +85°C 32 ST72F324BJ2T3 8 ST72F324BJ4T3 16 ST72F324BJ6T3 32 -40°C +125°C 155/167 1 ST72324B Table 28. Automotive Flash Order Codes Part Number Package ST72F324K2TA ST72F324K4TA ST72F324K6TA Flash Memory (KBytes) TQFP32 ST72F324K6TC 16 32 8 ST72F324J4TA 16 TQFP44 ST72F324J6TC -40°C +85°C 32 ST72F324J2TA ST72F324J6TA Temp. Range 8 -40°C +125°C -40°C +85°C 32 32 -40°C +125°C Automotive applications: ST72F324B part numbers are recommended for new designs. Please contact your local STMicroelectronics sales office for qualification details. 14.4 VERSION-SPECIFIC SALES CONDITIONS To satisfy the different customer requirements and to ensure that ST Standard Microcontrollers will consistently meet or exceed the expectations of each Market Segment, the Codification System for Standard Microcontrollers clearly distinguishes products intended for use in automotive environ- 156/167 1 ments, from products intended for use in non-automotive environments. It is the responsibility of the Customer to select the appropriate product for his application. ST72324B 14.5 SILICON IDENTIFICATION The various ST72F324, ST72F324B and ST72324B devices are identifiable both by the last letter of the Trace code marked on the device package and by the last 3 digits of the Internal Sales Type printed on the box label. Table 29. Silicon Identification (Automotive versions) Device Status ST72F324xxxx ST72324Bxxxx ST72324Bxxxx Fab Rousset Current production ST72F324xxxx Phoenix Phoenix Phoenix Under Qualification ST72F324Bxxxx Phoenix Memory 8K to 32K Flash 32K ROM 8K/16K ROM 8K to 32K Flash 8K/16K Flash 32K Flash Trace Code marked on device Internal Sales Types on box label “xxxxxxxxxW” 72F324xxxx$x5 “xxxxxxxxxA” “xxxxxxxxxB” 72324Bx6xx$x1 72324Bxxxx$x3 “xxxxxxxxx1” 72F324x6xx$x7 “xxxxxxxxx1” “xxxxxxxxxY” 72F324Bxxxx$x1 72F324Bxxxx$x4 Table 30. Silicon Identification (Standard and Industrial Versions) Device ST72F324xxxx Status Fab End of production Rousset Dec. 2005 Not recommended Phoenix for new designs ST72F324Bxxxx Phoenix Current production. Recommended for new designs ST72324Bxxxx Phoenix Memory Trace Code marked on device Internal Sales Types on box label “xxxxxxxxxW” 72F324xxxx$x5 “xxxxxxxxx1” 72F324xxxx$x7 8K/16K Flash “xxxxxxxxx1” 72F324Bxxxx$x1 32K Flash “xxxxxxxxxY” 72F324Bxxxx$x4 32K ROM “xxxxxxxxxA” 72324Bxxxx$x1 8K/16K ROM “xxxxxxxxxB” 72324Bxxxx$x3 8K to 32K Flash 157/167 1 ST72324B 14.6 DEVELOPMENT TOOLS STMicroelectronics offers a range of hardware and software development tools for the ST7 microcontroller family. Full details of tools available for the ST7 from third party manufacturers can be obtain from the STMicroelectronics Internet site: ➟ http//:mcu.st.com. Tools from these manufacturers include C compliers, emulators and gang programmers. Emulators Two types of emulators are available from ST for the ST72324 family: ■ ST7 DVP3 entry-level emulator offers a flexible and modular debugging and programming solution. SDIP42 & SDIP32 probes/adapters are included, other packages need a specific connection kit (refer to Table 31) ■ ST7 EMU3 high-end emulator is delivered with everything (probes, TEB, adapters etc.) needed to start emulating the ST72324 family. To configure it to emulate other ST7 subfamily devices, the active probe for the ST7EMU3 can be changed and the ST7EMU3 probe is designed for easy interchange of TEBs (Target Emulation Board). See Table 31. In-circuit Debugging Kit Two configurations are available from ST: ■ STXF521-IND/USB: Low-cost In-Circuit Debugging kit from Softec Microsystems. Includes STX-InDART/USB board (USB port) and a specific demo board for ST72521 (TQFP64) ■ ST7232X-SK/RAIS Low-cost in-circuit debugging/programming tool from Raisonance. Flash Programming tools ST7-STICK ST7 In-circuit Communication Kit, a complete software/hardware package for programming ST7 Flash devices. It connects to a host PC parallel port and to the target board or socket board via ST7 ICC connector. ■ ICC Socket Boards provide an easy to use and flexible means of programming ST7 Flash devices. They can be connected to any tool that supports the ST7 ICC interface, such as ST7 EMU3, ST7-DVP3, inDART, ST7-STICK, or many third-party development tools. Evaluation board ■ ST7232x-EVAL with ICC connector for programming capability. Provides direct connection to ST7-DVP3 emulator. Supplied with daughter boards (core module) for ST72F321, ST72F324 & ST72F521 (the ST72F321 & ST72F324 chips are not included) ■ Table 31. STMicroelectronics Development Tools Emulation Supported Products ST7 DVP3 Series Emulator Connection kit ST72324BJ, ST72F324J, ST72F324BJ ST7MDT20-DVP3 ST7MDT20-T44/ DVP ST72324BK, ST72F324K, ST72F324BK ST7MDT20-DVP3 ST7MDT20-T32/ DVP Programming ST7 EMU3 series Emulator Active Probe & T.E.B. ICC Socket Board ST7MDT20JEMU3 ST7MDT20J-TEB ST7SB20J/xx1 Note 1: Add suffix /EU, /UK, /US for the power supply of your region. 158/167 1 ST72324B 14.6.1 Socket and Emulator Adapter Information For information on the type of socket that is supplied with the emulator, refer to the suggested list of sockets in Table 32. Note: Before designing the board layout, it is recommended to check the overall dimensions of the socket as they may be greater than the dimensions of the device. For footprint and other mechanical information about these sockets and adapters, refer to the manufacturer’s datasheet (www.yamaichi.de for TQFP44 10 x 10 and www.ironwoodelectronics.com for TQFP32 7 x 7). Table 32. Suggested List of Socket Types Device Socket (supplied with ST7MDT20J-EMU3) Emulator Adapter (supplied with ST7MDT20J-EMU3) TQFP32 7 X 7 IRONWOOD SF-QFE32SA-L-01 IRONWOOD SK-UGA06/32A-01 TQFP44 10 X10 YAMAICHI IC149-044-*52-*5 YAMAICHI ICP-044-5 159/167 1 ST72324B 14.7 ST7 APPLICATION NOTES Table 33. ST7 Application Notes IDENTIFICATION DESCRIPTION APPLICATION EXAMPLES AN1658 SERIAL NUMBERING IMPLEMENTATION AN1720 MANAGING THE READ-OUT PROTECTION IN FLASH MICROCONTROLLERS AN1755 A HIGH RESOLUTION/PRECISION THERMOMETER USING ST7 AND NE555 EXAMPLE DRIVERS AN 969 SCI COMMUNICATION BETWEEN ST7 AND PC AN 970 SPI COMMUNICATION BETWEEN ST7 AND EEPROM AN 972 ST7 SOFTWARE SPI MASTER COMMUNICATION AN 973 SCI SOFTWARE COMMUNICATION WITH A PC USING ST72251 16-BIT TIMER AN 974 REAL TIME CLOCK WITH ST7 TIMER OUTPUT COMPARE AN 976 DRIVING A BUZZER THROUGH ST7 TIMER PWM FUNCTION AN 979 DRIVING AN ANALOG KEYBOARD WITH THE ST7 ADC AN 980 ST7 KEYPAD DECODING TECHNIQUES, IMPLEMENTING WAKE-UP ON KEYSTROKE AN1041 USING ST7 PWM SIGNAL TO GENERATE ANALOG OUTPUT (SINUSOÏD) AN1044 MULTIPLE INTERRUPT SOURCES MANAGEMENT FOR ST7 MCUS AN1046 UART EMULATION SOFTWARE AN1047 MANAGING RECEPTION ERRORS WITH THE ST7 SCI PERIPHERALS AN1048 ST7 SOFTWARE LCD DRIVER AN1078 PWM DUTY CYCLE SWITCH IMPLEMENTING TRUE 0% & 100% DUTY CYCLE AN1445 EMULATED 16 BIT SLAVE SPI AN1504 STARTING A PWM SIGNAL DIRECTLY AT HIGH LEVEL USING THE ST7 16-BIT TIMER GENERAL PURPOSE AN1476 LOW COST POWER SUPPLY FOR HOME APPLIANCES AN1709 EMC DESIGN FOR ST MICROCONTROLLERS AN1752 ST72324 QUICK REFERENCE NOTE PRODUCT EVALUATION AN1150 BENCHMARK ST72 VS PIC16 AN1151 PERFORMANCE COMPARISON BETWEEN ST72254 & PC16F876 AN1278 LIN (LOCAL INTERCONNECT NETWORK) SOLUTIONS PRODUCT MIGRATION AN1131 MIGRATING APPLICATIONS FROM ST72511/311/214/124 TO ST72521/321/324 PRODUCT OPTIMIZATION AN 982 USING ST7 WITH CERAMIC RESONATOR AN1014 HOW TO MINIMIZE THE ST7 POWER CONSUMPTION AN1015 SOFTWARE TECHNIQUES FOR IMPROVING MICROCONTROLLER EMC PERFORMANCE AN1070 ST7 CHECKSUM SELF-CHECKING CAPABILITY AN1181 ELECTROSTATIC DISCHARGE SENSITIVE MEASUREMENT AN1502 EMULATED DATA EEPROM WITH ST7 HDFLASH MEMORY ACCURATE TIMEBASE FOR LOW-COST ST7 APPLICATIONS WITH INTERNAL RC OSCILLAAN1530 TOR AN1636 UNDERSTANDING AND MINIMIZING ADC CONVERSION ERRORS PROGRAMMING AND TOOLS AN 978 ST7 VISUAL DEVELOP SOFTWARE KEY DEBUGGING FEATURES AN 983 KEY FEATURES OF THE COSMIC ST7 C-COMPILER PACKAGE AN 985 EXECUTING CODE IN ST7 RAM 160/167 1 ST72324B Table 33. ST7 Application Notes IDENTIFICATION DESCRIPTION AN 986 USING THE INDIRECT ADDRESSING MODE WITH ST7 AN 987 ST7 SERIAL TEST CONTROLLER PROGRAMMING AN 988 STARTING WITH ST7 ASSEMBLY TOOL CHAIN AN 989 GETTING STARTED WITH THE ST7 HIWARE C TOOLCHAIN AN1039 ST7 MATH UTILITY ROUTINES AN1064 WRITING OPTIMIZED HIWARE C LANGUAGE FOR ST7 AN1106 TRANSLATING ASSEMBLY CODE FROM HC05 TO ST7 AN1446 USING THE ST72521 EMULATOR TO DEBUG A ST72324 TARGET APPLICATION AN1478 PORTING AN ST7 PANTA PROJECT TO CODEWARRIOR IDE AN1575 ON-BOARD PROGRAMMING METHODS FOR XFLASH AND HDFLASH ST7 MCUS AN1576 IN-APPLICATION PROGRAMMING (IAP) DRIVERS FOR ST7 HDFLASH OR XFLASH MCUS AN1635 ST7 CUSTOMER ROM CODE RELEASE INFORMATION AN1754 DATA LOGGING PROGRAM FOR TESTING ST7 APPLICATIONS VIA ICC AN1796 FIELD UPDATES FOR FLASH BASED ST7 APPLICATIONS USING A PC COMM PORT SYSTEM OPTIMIZATION AN1711 SOFTWARE TECHNIQUES FOR COMPENSATING ST7 ADC ERRORS 161/167 1 ST72324B 15 KNOWN LIMITATIONS 15.1 ALL FLASH AND ROM DEVICES 15.1.1 Safe Connection of OSC1/OSC2 Pins The OSC1 and/or OSC2 pins must not be left unconnected otherwise the ST7 main oscillator may start and, in this configuration, could generate an fOSC clock frequency in excess of the allowed maximum (>16MHz.), putting the ST7 in an unsafe/undefined state. Refer to Section 6.2 on page 24. Note: For information on compatible devices, with safe connection of OSC1 and OSC2 and Clock security system feature please refer to the ST72325 datasheet. 15.1.2 External interrupt missed To avoid any risk if generating a parasitic interrupt, the edge detector is automatically disabled for one clock cycle during an access to either DDR and OR. Any input signal edge during this period will not be detected and will not generate an interrupt. This case can typically occur if the application refreshes the port configuration registers at intervals during runtime. Workaround The workaround is based on software checking the level on the interrupt pin before and after writing to the PxOR or PxDDR registers. If there is a level change (depending on the sensitivity programmed for this pin) the interrupt routine is invoked using the call instruction with three extra PUSH instructions before executing the interrupt routine (this is to make the call compatible with the IRET instruction at the end of the interrupt service routine). But detection of the level change does not make sure that edge occurs during the critical 1 cycle duration and the interrupt has been missed. This may lead to occurrence of same interrupt twice (one hardware and another with software call). To avoid this, a semaphore is set to '1' before checking the level change. The semaphore is changed to level '0' inside the interrupt routine. When a level change is detected, the semaphore status is checked and if it is '1' this means that the last interrupt has been missed. In this case, the interrupt routine is invoked with the call instruction. There is another possible case i.e. if writing to PxOR or PxDDR is done with global interrupts disabled (interrupt mask bit set). In this case, the semaphore is changed to '1' when the level 162/167 1 change is detected. Detecting a missed interrupt is done after the global interrupts are enabled (interrupt mask bit reset) and by checking the status of the semaphore. If it is '1' this means that the last interrupt was missed and the interrupt routine is invoked with the call instruction. To implement the workaround, the following software sequence is to be followed for writing into the PxOR/PxDDR registers. The example is for for Port PF1 with falling edge interrupt sensitivity. The software sequence is given for both cases (global interrupt disabled/enabled). Case 1: Writing to PxOR or PxDDR with Global Interrupts Enabled: LD A,#01 LD sema,A ; set the semaphore to '1' LD A,PFDR AND A,#02 LD X,A ; store the level before writing to PxOR/PxDDR LD A,#$90 LD PFDDR,A ; Write to PFDDR LD A,#$ff LD PFOR,A ; Write to PFOR LD A,PFDR AND A,#02 LD Y,A ; store the level after writing to PxOR/PxDDR LD A,X ; check for falling edge cp A,#02 jrne OUT TNZ Y jrne OUT LD A,sema ; check the semaphore status if edge is detected CP A,#01 jrne OUT call call_routine; call the interrupt routine OUT:LD A,#00 LD sema,A .call_routine ; entry to call_routine PUSH A PUSH X PUSH CC ST72324B .ext1_rt ; entry to interrupt routine LD A,#00 LD sema,A IRET Case 2: Writing to PxOR or PxDDR with Global Interrupts Disabled: SIM ; set the interrupt mask LD A,PFDR AND A,#$02 LD X,A ; store the level before writing to PxOR/PxDDR LD A,#$90 LD PFDDR,A; Write into PFDDR LD A,#$ff LD PFOR,A ; Write to PFOR LD A,PFDR AND A,#$02 LD Y,A ; store the level after writing to PxOR/ PxDDR LD A,X ; check for falling edge cp A,#$02 jrne OUT TNZ Y jrne OUT LD A,#$01 LD sema,A ; set the semaphore to '1' if edge is detected RIM ; reset the interrupt mask LD A,sema ; check the semaphore status CP A,#$01 jrne OUT call call_routine; call the interrupt routine RIM OUT: RIM JP while_loop .call_routine ; entry to call_routine PUSH A PUSH X PUSH CC .ext1_rt ; entry to interrupt routine LD A,#$00 LD sema,A IRET 15.1.3 Unexpected Reset Fetch If an interrupt request occurs while a "POP CC" instruction is executed, the interrupt controller does not recognise the source of the interrupt and, by default, passes the RESET vector address to the CPU. Workaround To solve this issue, a "POP CC" instruction must always be preceded by a "SIM" instruction. 15.1.4 Clearing active interrupts outside interrupt routine When an active interrupt request occurs at the same time as the related flag is being cleared, an unwanted reset may occur. Note: clearing the related interrupt mask will not generate an unwanted reset Concurrent interrupt context The symptom does not occur when the interrupts are handled normally, i.e. when: – The interrupt flag is cleared within its own interrupt routine – The interrupt flag is cleared within any interrupt routine – The interrupt flag is cleared in any part of the code while this interrupt is disabled If these conditions are not met, the symptom can be avoided by implementing the following sequence: Perform SIM and RIM operation before and after resetting an active interrupt request. Example: SIM reset interrupt flag RIM Nested interrupt context: The symptom does not occur when the interrupts are handled normally, i.e. when: – The interrupt flag is cleared within its own interrupt routine – The interrupt flag is cleared within any interrupt routine with higher or identical priority level – The interrupt flag is cleared in any part of the code while this interrupt is disabled If these conditions are not met, the symptom can be avoided by implementing the following sequence: 163/167 1 ST72324B PUSH CC SIM reset interrupt flag POP CC 15.1.5 16-bit Timer PWM Mode In PWM mode, the first PWM pulse is missed after writing the value FFFCh in the OC1R register (OC1HR, OC1LR). It leads to either full or no PWM during a period, depending on the OLVL1 and OLVL2 settings. 15.1.6 SCI Wrong Break duration Description A single break character is sent by setting and resetting the SBK bit in the SCICR2 register. In some cases, the break character may have a longer duration than expected: - 20 bits instead of 10 bits if M=0 - 22 bits instead of 11 bits if M=1. In the same way, as long as the SBK bit is set, break characters are sent to the TDO pin. This 164/167 1 may lead to generate one break more than expected. Occurrence The occurrence of the problem is random and proportional to the baudrate. With a transmit frequency of 19200 baud (fCPU=8MHz and SCIBRR=0xC9), the wrong break duration occurrence is around 1%. Workaround If this wrong duration is not compliant with the communication protocol in the application, software can request that an Idle line be generated before the break character. In this case, the break duration is always correct assuming the application is not doing anything between the idle and the break. This can be ensured by temporarily disabling interrupts. The exact sequence is: - Disable interrupts - Reset and Set TE (IDLE request) - Set and Reset SBK (Break Request) - Re-enable interrupts ST72324B 15.2 8/16K FLASH DEVICES ONLY Table 34. Port A and F Configuration: 15.2.1 39-Pulse ICC Entry Mode ICC mode entry using ST7 application clock (39 pulses) is not supported. External clock mode must be used (36 pulses). Refer to the ST7 Flash Programming Reference Manual. PLL PA3 PF4 PF1 OFF 0 1 0 ON 0 1 0 15.3 32K FLASH DEVICES ONLY 15.3.1 ADC Accuracy in 32K Flash Devices The ADC accuracy in 32K Flash Devices deviates from table in Section 12.13.3 on page 146 as follows: Symbol Max2) |ET| 6 |EO| 5 |EG| 4.5 |ED| 2 |EL| 3 Unit LSB Clock Disturbance Max. 2 clock cyTog- cles lost at each gling rising or falling edge of PF0 Max. 1 clock cycle 1 lost out of every 16 PF0 As a consequence, for cycle-accurate operations, these configurations are prohibited in either input or output mode. Workaround: To avoid this occurring, it is recommended to connect one of these pins to GND (PF4 or PF0) or VDD (PA3 or PF1). 15.5 32K ROM DEVICES ONLY The power consumption in Active Halt mode is 190µA typ. and 300µA max. 15.4 16K AND 8K ROM DEVICES ONLY 15.4.1 Read-Out Protection with LVD Read-out protection is not supported if the LVD is enabled. 15.4.2 I/O Port A and F Configuration When using an external quartz crystal or ceramic resonator, a few fOSC2 clock periods may be lost when the signal pattern in Table 34 occurs . This is because this pattern causes the device to enter test mode and return to user mode after a few clock periods. User program execution and I/O status are not changed, only a few clock cycles are lost. This happens with either one of the following configurations: PA3=0, PF4=1, PF1=0 while PLL option is disabled and PF0 is toggling PA3=0, PF4=1, PF1=0, PF0=1 while PLL option is enabled This is detailed in the following table 165/167 1 ST72324B 16 REVISION HISTORY Table 35. Revision History Date Revision Description of Changes Merged ST72F324 Flash with ST72324B ROM datasheet. Vt POR max modified in Section 12.4 on page 118 Added Figure 75 on page 138 05-May-2004 2.0 Modified VAREF min in “10-BIT ADC CHARACTERISTICS” on page 143 Modified I INJ for PB0 in Section 12.9 Added “Clearing active interrupts outside interrupt routine” on page 163 Modified “32K ROM DEVICES ONLY” on page 165 Removed Clock Security System (CSS) throughout document Added notes on ST72F324B 8K/16K Flash devices in Table 1 and Table 27 Corrected MCO description in Table 1 and Section 10.2 Modified VtPOR in Section 12.4 on page 118 Static current consumption modified in Section 12.9 on page 133 Updated footnote and Figure 74 and Figure 75 on page 138 30-Mar-2005 3 Modified Soldering information in Section 13.3 Updated Section 14 on page 151 Added Table 27 Modified Figure 7 and note 4 in “FLASH PROGRAM MEMORY” on page 17 Added limitation on ICC entry mode with 39 pulses to “KNOWN LIMITATIONS” on page 162 Added Section 16 on page 163 for ST72F324B 8K/16K Flash devices Modified “Internal Sales Types on box label” in Table 29 Removed notes related to ST72F324, refer to datasheet rev 3 for specifications on older devices. Note: This datasheet rev refers only to ST72F324B and ST72324B . Added oscillator diagram and table to Section 12.6.3 on page 124 12-Sep-2005 4 Increased Data retention max. parameter in Section 12.7.2 on page 129 Updated Current Consumption for in Section 12.5 on page 119 Updated Vt POR max in Section 12.4 on page 118 Added “external interrupt missed” in Section 15.1 on page 162 Updated ordering Section 14.3 on page 155 and Section 14.5 on page 157 Updated Development tools Section 14.6 on page 158 Added description of SICSR register at address 2Bh in “Hardware Register Map” on page 14 Highlighted note in SPI “Master Mode Operation” on page 81 06-Feb-2006 5 Changed description on port PF2 to added internal pull-up “Device Pin Description” on page 10 and “Port Configuration” on page 49 Added note 5 on analog input static current consumption “General Characteristics” on page 133 Changed “Static and Dynamic Latch-Up” on page 132 Updated notes in “THERMAL CHARACTERISTICS” on page 149 166/167 1 ST72324B Notes: Please Read Carefully: Information in this document is provided solely in connection with ST products. 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