INTEGRATED CIRCUITS P89C60X2/61X2 80C51 8-bit Flash microcontroller family 64KB Flash 512B/1024B RAM Product data Supersedes data of 2002 Jul 23 2003 Sep 11 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM In addition, the devices are static designs which offer a wide range of operating frequencies down to zero. Two software selectable modes of power reduction — idle mode and power-down mode — are available. The idle mode freezes the CPU while allowing the RAM, timers, serial port, and interrupt system to continue functioning. The power-down mode saves the RAM contents but freezes the oscillator, causing all other chip functions to be inoperative. Since the design is static, the clock can be stopped without loss of user data. Then the execution can be resumed from the point the clock was stopped. DESCRIPTION The Philips microcontrollers described in this data sheet are high-performance static 80C51 designs. They are manufactured in an advanced CMOS process and contain a non-volatile Flash program memory that is programmable in parallel (via a parallel programmer) or In-System Programmable (ISP) via boot loader. They support both 12-clock and 6-clock operation. The P89C60X2 and P89C61X2 contain 512 bytes RAM and 1024 bytes RAM respectively, 32 I/O lines, three 16-bit counter/timers, a six-source, four-priority level nested interrupt structure, a serial I/O port for either multi-processor communications, I/O expansion or full duplex UART, and on-chip oscillator and clock circuits. PWM PCA WD UART I 2C CAN SPI ADC bits/ch. I/O Pins Interrupts (External) Program Security Default Clock Rate Optional Clock Rate Max. Freq. at 6-clk / 12-clk (MHz) P89C60X2 512B – – 64K 3 – – n n – – – – 32 6 (2) n 12–clk 6-clk 20/33 – 0–20/33 P89C61X2 1024B – – 64K 3 – – n n – – – – 32 6 (2) n 12–clk 6-clk 20/33 – 0–20/33 RAM # of Timers Serial Interfaces Flash Timers OTP Memory For applications requiring more RAM, as well as more on-chip peripherals, see the P89C66x and P89C51Rx2 data sheets. ROM Type SELECTION TABLE Freq. Range at 3V (MHz) Freq. Range at 5V (MHz) NOTE: 1. I2C = Inter-Integrated Circuit Bus; CAN = Controller Area Network; SPI = Serial Peripheral Interface; PCA = Programmable Counter Array; ADC = Analog-to-Digital Converter; PWM = Pulse Width Modulation 2003 Sep 11 2 853-2400 30250 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM • LQFP, PLCC, and DIP packages • Dual Data Pointers • Three security bits • Four interrupt priority levels • Six interrupt sources • Four 8-bit I/O ports • Full-duplex enhanced UART FEATURES • 80C51 Central Processing Unit – 64 kbytes Flash – 512 bytes RAM (P89C60X2) – 1024 bytes RAM (P89C61X2) – Boolean processor – Fully static operation • In-System Programmable (ISP) Flash memory • 12-clock operation with selectable 6-clock operation (via software – Framing error detection or via parallel programmer) – Automatic address recognition • Memory addressing capability • Three 16-bit timers/counters T0, T1 (standard 80C51) and – Up to 64 kbytes ROM and 64 kbytes RAM additional T2 (capture and compare) • Power control modes: • Programmable clock-out pin • Watchdog timer • Asynchronous port reset • Low EMI (inhibit ALE, 6-clock mode) • Wake-up from Power Down by an external interrupt – Clock can be stopped and resumed – Idle mode – Power-down mode • Two speed ranges – 0 to 20 MHz with 6-clock operation – 0 to 33 MHz with 12-clock operation 2003 Sep 11 3 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM P89C60X2 ORDERING INFORMATION Type number Package Name Description Version Temperature R Range (°C) P89C60X2BA/00 PLCC44 plastic leaded chip carrier; 44 leads SOT187-2 0 to +70 P89C60X2BN/00 DIP40 plastic dual in-line package; 40 leads SOT129-1 0 to +70 P89C60X2BBD/00 LQFP44 plastic low profile quad flat package; 44 leads SOT389-1 0 to +70 P89C61X2 ORDERING INFORMATION Type number Package Name Description Version Temperature R Range (°C) P89C61X2BA/00 PLCC44 plastic lead chip carrier; 44 leads SOT187-2 0 to +70 P89C61X2BN/00 DIP40 plastic dual in-line package; 40 leads SOT129-1 0 to +70 P89C61X2BBD/00 LQFP44 plastic low profile quad flat package; 44 leads SOT389-1 0 to +70 ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁ PART NUMBER DERIVATION Memory P89C60X2 9 = Flash 0 = 512 bytes RAM 64 kbytes FLASH 1= 1024 bytes RAM 64 kbytes FLASH Temperature Range Package B = 0 °C to +70 °C A = PLCC BD = LQFP X2 = 6-clock mode available The following table illustrates the correlation between operating mode, power supply and maximum external clock frequency: Operating Mode Power Supply Maximum Clock Frequency 6-clock 5 V ± 10% 20 MHz 12-clock 5 V ± 10% 33 MHz 2003 Sep 11 4 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM BLOCK DIAGRAM 1 ACCELERATED 80C51 CPU (12-CLK MODE, 6-CLK MODE) 64 KBYTE CODE FLASH FULL-DUPLEX ENHANCED UART 512 / 1024 BYTE DATA RAM TIMER 0 TIMER 1 PORT 3 CONFIGURABLE I/Os TIMER 2 PORT 2 CONFIGURABLE I/Os WATCHDOG TIMER PORT 1 CONFIGURABLE I/Os PORT 0 CONFIGURABLE I/Os CRYSTAL OR RESONATOR OSCILLATOR su01664 2003 Sep 11 5 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM BLOCK DIAGRAM 2 (CPU-ORIENTED) P0.0–P0.7 P2.0–P2.7 PORT 0 DRIVERS PORT 2 DRIVERS VCC VSS RAM ADDR REGISTER PORT 0 LATCH RAM PORT 2 LATCH FLASH 8 B REGISTER STACK POINTER ACC PROGRAM ADDRESS REGISTER TMP1 TMP2 BUFFER ALU SFRs PC INCREMENTER TIMERS PSW 8 16 PSEN ALE/PROG EA / VPP TIMING AND CONTROL RST INSTRUCTION REGISTER PROGRAM COUNTER PD DPTR’S MULTIPLE PORT 1 LATCH PORT 3 LATCH PORT 1 DRIVERS PORT 3 DRIVERS P1.0–P1.7 P3.0–P3.7 OSCILLATOR XTAL1 XTAL2 SU01671 2003 Sep 11 6 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM LOGIC SYMBOL LOW PROFILE QUAD FLAT PACK PIN FUNCTIONS VCC VSS 44 34 PORT 0 XTAL1 ADDRESS AND 1 33 DATA BUS LQFP XTAL2 T2 T2EX PSEN PORT 2 RxD TxD INT0 INT1 T0 T1 WR RD Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ADDRESS BUS SU01672 PLASTIC LEADED CHIP CARRIER PIN FUNCTIONS 6 1 40 7 39 Pin 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Pin 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 * NO INTERNAL CONNECTION 28 Function P3.4/T0 P3.5/T1 P3.6/WR P3.7/RD XTAL2 XTAL1 VSS NIC* P2.0/A8 P2.1/A9 P2.2/A10 P2.3/A11 P2.4/A12 P2.5/A13 P2.6/A14 Pin 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Function P2.7/A15 PSEN ALE NIC* EA/VPP P0.7/AD7 P0.6/AD6 P0.5/AD5 P0.4/AD4 P0.3/AD3 P0.2/AD2 P0.1/AD1 P0.0/AD0 VCC T2EX/P1.1 2 39 P0.0/AD0 P1.2 3 38 P0.1/AD1 P1.3 4 37 P0.2/AD2 P1.4 5 36 P0.3/AD3 P1.5 6 35 P0.4/AD4 P1.6 7 34 P0.5/AD5 P1.7 8 33 P0.6/AD6 32 P0.7/AD7 RST 9 RxD/P3.0 10 TxD/P3.1 11 SU01062 DUAL IN-LINE PACKAGE 31 EA/VPP 30 ALE/PROG INT0/P3.2 12 29 PSEN INT1/P3.3 13 28 P2.7/A15 T0/P3.4 14 27 P2.6/A14 T1/P3.5 15 26 P2.5/A13 WR/P3.6 16 25 P2.4/A12 RD/P3.7 17 24 P2.3/A11 XTAL2 18 23 P2.2/A10 XTAL1 19 22 P2.1/A9 VSS 20 21 P2.0/A8 SU01780 2003 Sep 11 Pin 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Function P0.6/AD6 P0.5/AD5 P0.4/AD4 P0.3/AD3 P0.2/AD2 P0.1/AD1 P0.0/AD0 VCC NIC* P1.0/T2 P1.1/T2EX P1.2 P1.3 P1.4 SU01487 40 VCC 29 18 22 Function VSS NIC* P2.0/A8 P2.1/A9 P2.2/A10 P2.3/A11 P2.4/A12 P2.5/A13 P2.6/A14 P2.7/A15 PSEN ALE NIC* EA/VPP P0.7/AD7 PLASTIC DUAL IN-LINE PACKAGE PIN FUNCTIONS T2/P1.0 1 17 Function NIC* P1.0/T2 P1.1/T2EX P1.2 P1.3 P1.4 P1.5 P1.6 P1.7 RST P3.0/RxD NIC* P3.1/TxD P3.2/INT0 P3.3/INT1 Function P1.5 P1.6 P1.7 RST P3.0/RxD NIC* P3.1/TxD P3.2/INT0 P3.3/INT1 P3.4/T0 P3.5/T1 P3.6/WR P3.7/RD XTAL2 XTAL1 * NO INTERNAL CONNECTION PLCC Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 23 12 ALE/PROG PORT 3 SECONDARY FUNCTIONS 11 PORT 1 RST EA/VPP 7 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM PIN DESCRIPTIONS PIN NUMBER MNEMONIC VSS VCC PLCC 22 44 DIP 20 40 LQFP 16 38 TYPE I I P0.0-0.7 43–36 39–32 37–30 I/O 2–9 1–8 40–44, 1–3 I/O 2 1 40 I/O 3 24–31 2 21–28 41 18–25 I I/O 11, 13–19 10–17 5, 7–13 I/O RST 11 13 14 15 16 17 18 19 10 10 11 12 13 14 15 16 17 9 5 7 8 9 10 11 12 13 4 I O I I I I O O I ALE/PROG 33 30 27 O PSEN 32 29 26 O EA/VPP 35 31 29 I P1.0–P1.7 P2.0–P2.7 P3.0–P3.7 2003 Sep 11 NAME AND FUNCTION Ground: 0 V reference. Power Supply: This is the power supply voltage for normal, idle, and power-down operation. Port 0: Port 0 is an open-drain, bidirectional I/O port. Port 0 pins that have 1s written to them float and can be used as high-impedance inputs. Port 0 is also the multiplexed low-order address and data bus during accesses to external program and data memory. In this application, it uses strong internal pull-ups when emitting 1s. Port 0 also outputs the code bytes during program verification and received code bytes during Flash programming. External pull-ups are required during program verification. Port 1: Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. Port 1 pins that have 1s written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 1 pins that are externally pulled low will source current because of the internal pull-ups. (See DC Electrical Characteristics: IIL). Port 1 also receives the low-order address byte during program memory verification. Alternate functions for Port 1 include: T2 (P1.0): Timer/Counter 2 external count input/clockout (see Programmable Clock-Out) T2EX (P1.1): Timer/Counter 2 Reload/Capture/Direction control Port 2: Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. Port 2 pins that have 1s written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 2 pins that are externally being pulled low will source current because of the internal pull-ups. (See DC Electrical Characteristics: IIL). Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use 16-bit addresses (MOVX @DPTR). In this application, it uses strong internal pull-ups when emitting 1s. During accesses to external data memory that use 8-bit addresses (MOV @Ri), port 2 emits the contents of the P2 special function register. Some Port 2 pins receive the high order address bits during Flash programming and verification. Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. Port 3 pins that have 1s written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 3 pins that are externally being pulled low will source current because of the pull-ups. (See DC Electrical Characteristics: IIL). Port 3 also serves the special features of the 80C51 family, as listed below: RxD (P3.0): Serial input port TxD (P3.1): Serial output port INT0 (P3.2): External interrupt INT1 (P3.3): External interrupt T0 (P3.4): Timer 0 external input T1 (P3.5): Timer 1 external input WR (P3.6): External data memory write strobe RD (P3.7): External data memory read strobe Reset: A high on this pin for two machine cycles while the oscillator is running, resets the device. An internal diffused resistor to VSS permits a power-on reset using only an external capacitor to VCC. Address Latch Enable/Program Pulse: Output pulse for latching the low byte of the address during an access to external memory. In normal operation, ALE is emitted at a constant rate of 1/6 (12-clk) or 1/3 (6-clk Mode) the oscillator frequency, and can be used for external timing or clocking. Note that one ALE pulse is skipped during each access to external data memory. This pin is also the program pulse input (PROG) during Flash programming. ALE can be disabled by setting SFR auxiliary.0. With this bit set, ALE will be active only during a MOVX instruction. Program Store Enable: The read strobe to external program memory. When the device is executing code from the external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory. PSEN is not activated during fetches from internal program memory. External Access Enable/Programming Supply Voltage: EA must be externally held low to enable the device to fetch code from external program memory locations 0000H to FFFFH. If EA is held high, the device executes from internal program memory. This pin also receives the 5 V / 12 V programming supply voltage (VPP) during Flash programming. If security bit 1 is programmed, EA will be internally latched on Reset. 8 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM PIN NUMBER MNEMONIC XTAL1 PLCC 21 DIP 19 LQFP 15 TYPE NAME AND FUNCTION I Crystal 1: Input to the inverting oscillator amplifier and input to the internal clock generator circuits. O Crystal 2: Output from the inverting oscillator amplifier. XTAL2 20 18 14 NOTE: To avoid “latch-up” effect at power-on, the voltage on any pin at any time must not be higher than VCC + 0.5 V or VSS – 0.5 V, respectively. 2003 Sep 11 9 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM SPECIAL FUNCTION REGISTERS (see notes on next page) SYMBOL DESCRIPTION DIRECT ADDRESS ACC* AUXR# AUXR1# B* CKCON DPTR: DPH DPL Accumulator Auxiliary Auxiliary 1 B register Clock Control Register Data Pointer (2 bytes) Data Pointer High Data Pointer Low E0H 8EH A2H F0H 8FH IE* Interrupt Enable A8H MSB BIT ADDRESS, SYMBOL, OR ALTERNATIVE PORT FUNCTION LSB E7 E6 E5 E4 E3 E2 E1 E0 – – – – – – – – – GF2 – 0 EXTRAM AO DPS F7 F6 F5 F4 F3 F2 F1 F0 – WDX2 – – – – – X2 – 83H 82H AF AE AD AC AB AA A9 A8 EA – ET2 ES ET1 EX1 ET0 EX0 BF BE BD BC BB BA B9 B8 – – PT2 PT2H PS PSH PT1 PT1H PX1 PX1H PT0 PT0H PX0 PX0H Interrupt Priority Interrupt Priority High B8H B7H – – 87 86 85 84 83 82 81 80 P0* Port 0 80H AD7 AD6 AD5 AD4 AD3 AD2 AD1 AD0 97 96 95 94 93 92 91 90 P2* Port 1 Port 2 90H A0H – – – – – T2EX T2 A5 A4 A3 A2 A1 A0 AD15 AD14 AD13 AD12 AD11 AD10 AD9 AD8 B7 B6 B5 B4 B3 B2 B1 B0 T1 T0 INT1 INT0 TxD RxD FFH 00xx0000B RD WR PCON#1 Power Control 87H SMOD1 SMOD0 – POF GF1 GF0 PD IDL D7 D6 D5 D4 D3 D2 D1 D0 AC F0 RS1 RS0 OV – P PSW* RACAP2H# RACAP2L# SADDR# SADEN# SBUF Program Status Word Timer 2 Capture High Timer 2 Capture Low Slave Address Slave Address Mask Serial Data Buffer D0H CBH CAH A9H B9H 99H CY 9F 9E 9D 9C 9B 9A 99 98 SCON* SP Serial Control Stack Pointer 98H 81H SM0/FE SM1 SM2 REN TB8 RB8 TI RI 8F 8E 8D 8C 8B 8A 89 88 TCON* Timer Control 88H TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0 CF CE CD CC CB CA C9 C8 TF2 – EXF2 – RCLK – TCLK – EXEN2 – TR2 – C/T2 T2OE CP/RL2 DCEN GATE C/T M1 M0 GATE C/T M1 M0 2003 Sep 11 FFH A6 B0H C8H C9H 8CH 8DH CDH 8AH 8BH CCH 89H A6H xx000000B xx000000B – Port 3 Timer 2 Control Timer 2 Mode Control Timer High 0 Timer High 1 Timer High 2 Timer Low 0 Timer Low 1 Timer Low 2 Timer Mode Watchdog Timer Reset 0x000000B A7 P3* T2CON* T2MOD# TH0 TH1 TH2# TL0 TL1 TL2# TMOD WDTRST 00H xxxxxx00B xxx000x0B 00H x0xxxxx0B 00H 00H IP* IPH# P1* RESET VALUE 10 FFH FFH 000000x0B 00H 00H 00H 00H xxxxxxxxB 00H 07H 00H 00H xxxxxx00B 00H 00H 00H 00H 00H 00H 00H Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM NOTES: Special Function Registers (SFRs) accesses are restricted in the following ways: 1. Do not attempt to access any SFR locations not defined. 2. Accesses to any defined SFR locations must be strictly for the functions for the SFRs. 3. SFR bits labeled ‘–’, ‘0’ or ‘1’ can ONLY be written and read as follows: ‘–’ MUST be written with ‘0’, but can return any value when read (even if it was written with ‘0’). It is a reserved bit and may be used in future derivatives. ‘0’ MUST be written with ‘0’, and will return a ‘0’ when read. ‘1’ MUST be written with ‘1’, and will return a ‘1’ when read. *: SFRs are bit addressable. #: SFRs are modified from or added to the 80C51 SFRs. –: Reserved bits (see note above). 1: Reset value depends on reset source. 2003 Sep 11 11 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM • Programmable security for the code in the Flash. • 10,000 minimum erase/program cycles for each byte. • 10-year minimum data retention. FLASH EPROM MEMORY GENERAL DESCRIPTION The P89C60X2/61X2 Flash memory augments EPROM functionality with in-circuit electrical erasure and programming. The Flash can be read and written as bytes. The Chip Erase operation will erase the entire program memory. The Block Erase function can erase any Flash block. In-system programming (ISP) and standard parallel programming are both available. On-chip erase and write timing generation contribute to a user friendly programming interface. FLASH PROGRAMMING AND ERASURE There are two methods of erasing or programming of the Flash memory that may be used. First, the on-chip ISP boot loader may be invoked. Second, the Flash may be programmed or erased using parallel method by using a commercially available EPROM programmer. The parallel programming method used by these devices is similar to that used by EPROM 87C51, but it is not identical, and the commercially available programmer will need to have support for these devices. The P89C60X2/61X2 Flash reliably stores memory contents even after 10,000 erase and program cycles. The cell is designed to optimize the erase and programming mechanisms. In addition, the combination of advanced tunnel oxide processing and low internal electric fields for erase and programming operations produces reliable cycling. The P89C60X2/61X2 uses a +5 V VPP supply to perform the Program/Erase algorithms (12 V tolerant). FLASH MEMORY CHARACTERISTICS Flash User Code Memory Organization FEATURES • Flash EPROM internal program memory with Block Erase. • Internal 1-kbyte fixed BootROM, containing low-level in-system The P89C60X2/61X2 contains 64 kbytes Flash user code program memory organized into 4-kbyte blocks (see Figure 1). Boot ROM programming routines and a default serial loader. When the microcontroller programs its Flash memory during ISP, all of the low level details are handled by code that is contained in a 1 kbyte BootROM. BootROM operations include: erase block, program byte, verify byte, program security bit, etc. • Loader in BootROM allows in-system programming via the serial port. • Up to 64 kbytes external program memory if the internal program memory is disabled (EA = 0). Clock Mode • Programming and erase voltage +5 V (+12 V tolerant). • Read/Programming/Erase using ISP: The clock mode feature sets operating frequency to be 1/12 or 1/6 of the oscillator frequency. The clock mode configuration bit, FX2, is located in the Security Block (See Table 1). FX2, when programmed, will override the SFR clock mode bit (X2) in the CKCON register. If FX2 is erased, then the SFR bit (X2) may be used to select between 6-clock and 12-clock mode. – Byte Programming (8 ms). – Typical erase times: Block Erase (4 kbytes) in 3 seconds. Full-chip erase in 15 seconds. • Parallel programming with 87C51 compatible hardware interface to programmer. 2003 Sep 11 12 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Table 1. CLOCK MODE CONFIG BIT (FX2) X2 bit in CKCON DESCRIPTION erased 0 12-clock mode (default) erased 1 6-clock mode programmed x 6-clock mode NOTE: 1. Default clock mode after ChipErase is set to 12-clock. FFFF BLOCK 15 BOOT ROM BLOCK 14 (1 kB) BLOCK 13 P89C60X2 P89C61X2 BLOCK 12 C000 BLOCK 11 BLOCK 10 PROGRAM ADDRESS BLOCK 9 BLOCK 8 8000 BLOCK 7 BLOCK 6 Each block is 4 kbytes in size BLOCK 5 BLOCK 4 4000 BLOCK 3 BLOCK 2 2000 BLOCK 1 BLOCK 0 0000 SU01673 Figure 1. Flash Memory Configuration Power-On Reset Code Execution Hardware Activation of the Boot Loader The P89C60X2/61X2 contains a special Flash register, the STATUS BYTE. At the falling edge of reset, the P89C60X2/61X2 examines the contents of the Status Byte. If the Status Byte is set to zero, power-up execution starts at location 0000H, which is the normal start address of the user’s application code. When the Status Byte is set to a value other than zero, the factory masked-ROM ISP boot loader is invoked. The factory default for the Status Byte is FFh. Once set to 00h, the Status Byte can only be changed back to FFh by a full-chip erase operation when using ISP. The boot loader can also be executed by holding PSEN LOW, EA greater than VIH (such as +5 V), and ALE HIGH (or not connected) at the falling edge of RESET. This is the same effect as having a non-zero status byte. This allows an application to be built that will normally execute the end user’s code but can be manually forced into ISP operation. 2003 Sep 11 After programming the Flash, the status byte should be programmed to zero in order to allow execution of the user’s application code beginning at address 0000H. 13 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM VCC RST XTAL2 VPP +5 V (+12 V tolerant) VCC +5 V TxD TxD RxD RxD P89C60X2 P89C61X2 VSS XTAL1 VSS SU01674 Figure 2. In-System Programming with a Minimum of Pins :NNAAAARRDD..DDCC<crlf> In-System Programming (ISP) The In-System Programming (ISP) is performed without removing the microcontroller from the system. The In-System Programming (ISP) facility consists of a series of internal hardware resources coupled with internal firmware to facilitate remote programming of the P89C60X2/61X2 through the serial port. This firmware is provided by Philips and embedded within each P89C60X2/61X2 device. In the Intel Hex record, the “NN” represents the number of data bytes in the record. The P89C60X2/61X2 will accept up to 16 (10H) data bytes. The “AAAA” string represents the address of the first byte in the record. If there are zero bytes in the record, this field is often set to 0000. The “RR” string indicates the record type. A record type of “00” is a data record. A record type of “01” indicates the end-of-file mark. In this application, additional record types will be added to indicate either commands or data for the ISP facility. The maximum number of data bytes in a record is limited to 16 (decimal). ISP commands are summarized in Table 2. The Philips In-System Programming (ISP) facility has made in-circuit programming in an embedded application possible with a minimum of additional expense in components and circuit board area. As a record is received by the P89C60X2/61X2, the information in the record is stored internally and a checksum calculation is performed. The operation indicated by the record type is not performed until the entire record has been received. Should an error occur in the checksum, the P89C60X2/61X2 will send an “X” out the serial port indicating a checksum error. If the checksum calculation is found to match the checksum in the record, then the command will be executed. In most cases, successful reception of the record will be indicated by transmitting a “.” character out the serial port (displaying the contents of the internal program memory is an exception). The ISP function uses five pins: TxD, RxD, VSS, VCC, and VPP (see Figure 2). Only a small connector needs to be available to interface your application to an external circuit in order to use this feature. The VPP supply should be adequately decoupled and VPP not allowed to exceed datasheet limits. Free ISP software is available from the Embedded Systems Academy: “FlashMagic” 1. Direct your browser to the following page: http://www.esacademy.com/software/flashmagic/ 2. Download Flashmagic In the case of a Data Record (record type 00), an additional check is made. A “.” character will NOT be sent unless the record checksum matched the calculated checksum and all of the bytes in the record were successfully programmed. For a data record, an “X” indicates that the checksum failed to match, and an “R” character indicates that one of the bytes did not properly program. It is necessary to send a type 02 record (specify oscillator frequency) to the P89C60X2/61X2 before programming data. 3. Execute “flashmagic.exe” to install the software Using the In-System Programming (ISP) The ISP feature allows for a wide range of baud rates to be used in your application, independent of the oscillator frequency. It is also adaptable to a wide range of oscillator frequencies. This is accomplished by measuring the bit-time of a single bit in a received character. This information is then used to program the baud rate in terms of timer counts based on the oscillator frequency. The ISP feature requires that an initial character (an uppercase U) be sent to the P89C60X2/61X2 to establish the baud rate. The ISP firmware provides auto-echo of received characters. The ISP facility was designed to that specific crystal frequencies were not required in order to generate baud rates or time the programming pulses. The user thus needs to provide the P89C60X2/61X2 with information required to generate the proper timing. Record type 02 is provided for this purpose. Once baud rate initialization has been performed, the ISP firmware will only accept Intel Hex-type records. Intel Hex records consist of ASCII characters used to represent hexadecimal values and are summarized below: 2003 Sep 11 14 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Table 2. Intel-Hex Records Used by In-System Programming RECORD TYPE COMMAND/DATA FUNCTION 00 Program Data :nnaaaa00dd....ddcc Where: nn = number of bytes (hex) in record aaaa = memory address of first byte in record dd....dd = data bytes cc = checksum Example: :10008000AF5F67F0602703E0322CFA92007780C3FD 01 End of File (EOF), no operation :xxxxxx01cc Where: xxxxxx = required field, but value is a “don’t care” cc = checksum Example: :00000001FF 03 Miscellaneous Write Functions :nnxxxx03ffssddcc Where: nn = number of bytes (hex) in record xxxx = required field, but value is a “don’t care” 03 = Write Function ff = subfunction code ss = selection code dd = data input (as needed) cc = checksum Subfunction Code = 04 (Set Status Byte to 00h) ff = 04 ss = don’t care Example: :020000030400F7 set status byte to 00h (device executes user code after Reset) Subfunction Code = 05 (Program Security Bits) ff = 05 ss = 00 program security bit 1 (inhibit writing to Flash) 01 program security bit 2 (inhibit Flash verify) 02 program security bit 3 (disable external memory) Example: :020000030501F5 program security bit 2 Subfunction Code = 06 (Program Flash X2 bit) ff = 06 ss = 02 program FX2 bit (dd = 80) ⇒ 6–clk. mode enabled dd = data Example 1: :0300000306028072 program FX2 bit (enable 6–clk. mode) 2003 Sep 11 15 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM RECORD TYPE 03 (cont.) COMMAND/DATA FUNCTION Subfunction Code = 07 (Full Chip Erase) Erases all blocks, security bits, and sets status byte to default values ff = 07 ss = don’t care dd = don’t care Example: :0100000307F5 full chip erase Subfunction Code = 0C (Erase 4k blocks) ff = 0C ss = block code as shown below: block 0, 0k ~ 4k, 00H block 1, 4k ~ 8k, 10H block 2, 8k ~ 12k, 20H block 3, 12k ~ 16k, 30H block 4, 16k ~ 20k, 40H block 5, 20k ~ 24k, 50H block 6, 24k ~ 28k, 60H block 7, 28k ~ 32k, 70H block 8, 32k ~ 36k, 80H block 9, 36k ~ 40k, 90H block 10, 40k ~ 44k, A0H block 11, 44k ~ 48k, B0H block 12, 48k ~ 52k, C0H block 13, 52k ~ 56k, D0H block 14, 56k ~ 60k, E0H block 15, 60k ~ 64k, F0H Example: :020000030C20CF erase 4k block 2 04 Display Device Data or Blank Check – Record type 04 causes the contents of the entire Flash array to be sent out the serial port in a formatted display. This display consists of an address and the contents of 16 bytes starting with that address. No display of the device contents will occur if security bit 2 has been programmed. Data to the serial port is initiated by the reception of any character and terminated by the reception of any character. General Format of Function 04 :05xxxx04sssseeeeffcc Where: 05 = number of bytes (hex) in record xxxx = required field, but value is a “don’t care” 04 = “Display Device Data or Blank Check” function code ssss = starting address eeee = ending address ff = subfunction 00 = display data 01 = blank check 02 = display data in data block (valid addresses: 0001 ~ 0FFFH) cc = checksum Example 1: :0500000440004FFF0069 display 4000–4FFF Example 2: :0500000400000FFF02E7 display data in data block (the data at address 0000 is invalid) 2003 Sep 11 16 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM RECORD TYPE 05 COMMAND/DATA FUNCTION Miscellaneous Read Functions General Format of Function 05 :02xxxx05ffsscc Where: 02 = number of bytes (hex) in record xxxx = required field, but value is a “don’t care” 05 = “Miscellaneous Read” function code ffss = subfunction and selection code 0000 = read signature byte – manufacturer id (15H) 0001 = read signature byte – device id # 1 (C2H) 0002 = read signature byte – device id # 2 P89C60X2 = EFh P89C61X2 = F0h 0003 = read FX2 bit 0080 = read ROM code revision 0700 = read security bits 0701 = read status byte cc = checksum Example 1: :020000050001F8 read signature byte – device id # 1 Example 2: :020000050003F6 read FX2 bit (bit 7 = 0 represents 12-clk mode, bit 7 = 1 represents 6-clk mode) Example 3: :02000005008079 read ROM code revision (0A: Rev. A; 0B: Rev. B, etc.) 06 Direct Load of Baud Rate General Format of Function 06 :02xxxx06hhllcc Where: 02 = number of bytes (hex) in record xxxx = required field, but value is a “don’t care” 06 = ”Direct Load of Baud Rate” function code hh = high byte of Timer 2 ll = low byte of Timer 2 cc = checksum Example: :02000006F500F3 2003 Sep 11 17 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Security The security feature protects against software piracy and prevents the contents of the FLASH from being read. The Security Lock bits are located in FLASH. The P89C60X2/61X2 has 3 programmable security lock bits that will provide different levels of protection for the on-chip code and data (see Table 3). Unlike the ROM and OTP versions, the security lock bits are independent. LB3 includes the security protection of LB1. Table 3. SECURITY LOCK BITS1 PROTECTION DESCRIPTION Level LB1 MOVC instructions executed from external program memory are disabled from fetching code bytes from internal memory. LB2 Program verification is disabled LB3 External execution is disabled. NOTE: 1. The security lock bits are independent. 2003 Sep 11 18 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM OSCILLATOR CHARACTERISTICS Using the oscillator, XTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier. The pins can be configured for use as an on-chip oscillator, as shown in the logic symbol. Programmable Clock-Out Pin A 50% duty cycle clock can be programmed to be output on P1.0. This pin, besides being a regular I/O pin, has two alternate functions. It can be programmed: To drive the device from an external clock source, XTAL1 should be driven while XTAL2 is left unconnected. However, minimum and maximum high and low times specified in the data sheet must be observed. 1. to input the external clock for Timer/Counter 2, or 2. to output a 50% duty cycle clock ranging from 61 Hz to 4 MHz at a 16 MHz operating frequency in 12-clock mode (122 Hz to 8 MHz in 6-clock mode). Clock Control Register (CKCON) To configure the Timer/Counter 2 as a clock generator, bit C/T2 (in T2CON) must be cleared and bit T20E in T2MOD must be set. Bit TR2 (T2CON.2) also must be set to start the timer. This device provides control of the 6-clock/12-clock mode by both an SFR bit (bit X2 in register CKCON) and a Flash bit (bit FX2, located in the Security Block). When X2 is 0, 12-clock mode is activated. By setting this bit to 1, the system is switching to 6-clock mode. Having this option implemented as SFR bit, it can be accessed anytime and changed to either value. Changing X2 from 0 to 1 will result in executing user code at twice the speed, since all system time intervals will be divided by 2. Changing back from 6-clock to 12-clock mode will slow down running code by a factor of 2. The Flash clock control bit (FX2) activates the 6-clock mode when programmed using a parallel programmer, superceding the X2 bit (CKCON.0). Please also see Table 4 below. The Clock-Out frequency depends on the oscillator frequency and the reload value of Timer 2 capture registers (RCAP2H, RCAP2L) as shown in this equation: n Where: n = 2 in 6-clock mode, 4 in 12-clock mode. (RCAP2H,RCAP2L) = the content of RCAP2H and RCAP2L taken as a 16-bit unsigned integer. Table 4. FX2 clock mode bit (can only be set by parallel programmer) X2 bit (CKCON.0) CPU clock mode erased 0 12-clock mode (default) erased 1 6-clock mode programmed X 6-clock mode Oscillator Frequency (65536–RCAP2H, RCAP2L) In the Clock-Out mode Timer 2 roll-overs will not generate an interrupt. This is similar to when it is used as a baud-rate generator. It is possible to use Timer 2 as a baud-rate generator and a clock generator simultaneously. Note, however, that the baud-rate and the Clock-Out frequency will be the same. RESET A reset is accomplished by holding the RST pin HIGH for at least two machine cycles (24 oscillator periods in 12-clock and 12 oscillator periods in 6-clock mode), while the oscillator is running. To insure a reliable power-up reset, the RST pin must be high long enough to allow the oscillator time to start up (normally a few milliseconds) plus two machine cycles, unless it has been set to 6-clock operation using a parallel programmer. LOW POWER MODES Stop Clock Mode The static design enables the clock speed to be reduced down to 0 MHz (stopped). When the oscillator is stopped, the RAM and Special Function Registers retain their values. This mode allows step-by-step utilization and permits reduced system power consumption by lowering the clock frequency down to any value. For lowest power consumption the Power Down mode is suggested. Idle Mode In idle mode (see Table 5), the CPU puts itself to sleep while all of the on-chip peripherals stay active. The instruction to invoke the idle mode is the last instruction executed in the normal operating mode before the idle mode is activated. The CPU contents, the on-chip RAM, and all of the special function registers remain intact during this mode. The idle mode can be terminated either by any enabled interrupt (at which time the process is picked up at the interrupt service routine and continued), or by a hardware reset which starts the processor in the same manner as a power-on reset. 2003 Sep 11 19 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM machine cycles before the internal reset algorithm takes control. On-chip hardware inhibits access to internal RAM in this event, but access to the port pins is not inhibited. To eliminate the possibility of an unexpected write when Idle is terminated by reset, the instruction following the one that invokes Idle should not be one that writes to a port pin or to external memory. Power-Down Mode To save even more power, a Power Down mode (see Table 5) can be invoked by software. In this mode, the oscillator is stopped and the instruction that invoked Power Down is the last instruction executed. The on-chip RAM and Special Function Registers retain their values down to 2.0 V and care must be taken to return VCC to the minimum specified operating voltages before the Power Down Mode is terminated. ONCE Mode The ONCE (“On-Circuit Emulation”) Mode facilitates testing and debugging of systems without the device having to be removed from the circuit. The ONCE Mode is invoked in the following way: Either a hardware reset or external interrupt can be used to exit from Power Down. Reset redefines all the SFRs but does not change the on-chip RAM. An external interrupt allows both the SFRs and the on-chip RAM to retain their values. 1. Pull ALE low while the device is in reset and PSEN is high; 2. Hold ALE low as RST is deactivated. To properly terminate Power Down, the reset or external interrupt should not be executed before VCC is restored to its normal operating level and must be held active long enough for the oscillator to restart and stabilize (normally less than 10 ms). While the device is in ONCE Mode, the Port 0 pins go into a float state, and the other port pins and ALE and PSEN are weakly pulled high. The oscillator circuit remains active. While the device is in this mode, an emulator or test CPU can be used to drive the circuit. Normal operation is restored when a normal reset is applied. To terminate Power Down with an external interrupt, INT0 or INT1 must be enabled and configured as level-sensitive. Holding the pin low restarts the oscillator but bringing the pin back high completes the exit. Once the interrupt is serviced, the next instruction to be executed after RETI will be the one following the instruction that put the device into Power Down. POWER-ON FLAG The Power-On Flag (POF) is set by on-chip circuitry when the VCC level on the P89C60X2/61X2 rises from 0 to 5 V. The POF bit can be set or cleared by software allowing a user to determine if the reset is the result of a power-on or a warm start after powerdown. The VCC level must remain above 3 V for the POF to remain unaffected by the VCC level. Design Consideration When the idle mode is terminated by a hardware reset, the device normally resumes program execution from where it left off, up to two Table 5. External Pin Status During Idle and Power-Down Modes PROGRAM MEMORY ALE PSEN PORT 0 PORT 1 PORT 2 PORT 3 Idle MODE Internal 1 1 Data Data Data Data Idle External 1 1 Float Data Address Data Power-down Internal 0 0 Data Data Data Data Power-down External 0 0 Float Data Data Data Mode 0 operation is the same for Timer 0 as for Timer 1. There are two different GATE bits, one for Timer 1 (TMOD.7) and one for Timer 0 (TMOD.3). TIMER 0 AND TIMER 1 OPERATION Timer 0 and Timer 1 The “Timer” or “Counter” function is selected by control bits C/T in the Special Function Register TMOD. These two Timer/Counters have four operating modes, which are selected by bit-pairs (M1, M0) in TMOD. Modes 0, 1, and 2 are the same for both Timers/Counters. Mode 3 is different. The four operating modes are described in the following text. Mode 1 Mode 1 is the same as Mode 0, except that the Timer register is being run with all 16 bits. Mode 2 Mode 2 configures the Timer register as an 8-bit Counter (TLn) with automatic reload, as shown in Figure 6. Overflow from TLn not only sets TFn, but also reloads TLn with the contents of THn, which is preset by software. The reload leaves THn unchanged. Mode 0 Putting either Timer into Mode 0 makes it look like an 8048 Timer, which is an 8-bit Counter with a divide-by-32 prescaler. Figure 4 shows the Mode 0 operation. Mode 2 operation is the same for Timer 0 as for Timer 1. In this mode, the Timer register is configured as a 13-bit register. As the count rolls over from all 1s to all 0s, it sets the Timer interrupt flag TFn. The counted input is enabled to the Timer when TRn = 1 and either GATE = 0 or INTn = 1. (Setting GATE = 1 allows the Timer to be controlled by external input INTn, to facilitate pulse width measurements). TRn is a control bit in the Special Function Register TCON (Figure 5). Mode 3 Timer 1 in Mode 3 simply holds its count. The effect is the same as setting TR1 = 0. Timer 0 in Mode 3 establishes TL0 and TH0 as two separate counters. The logic for Mode 3 on Timer 0 is shown in Figure 7. TL0 uses the Timer 0 control bits: C/T, GATE, TR0, and TF0 as well as pin INT0. TH0 is locked into a timer function (counting machine cycles) and takes over the use of TR1 and TF1 from Timer 1. Thus, TH0 now controls the “Timer 1” interrupt. The 13-bit register consists of all 8 bits of THn and the lower 5 bits of TLn. The upper 3 bits of TLn are indeterminate and should be ignored. Setting the run flag (TRn) does not clear the registers. 2003 Sep 11 20 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Mode 3 is provided for applications requiring an extra 8-bit timer on the counter. With Timer 0 in Mode 3, an 80C51 can look like it has three Timer/Counters. When Timer 0 is in Mode 3, Timer 1 can be TMOD turned on and off by switching it out of and into its own Mode 3, or can still be used by the serial port as a baud rate generator, or in fact, in any application not requiring an interrupt. Address = 89H Reset Value = 00H Not Bit Addressable 7 6 5 4 3 2 1 0 GATE C/T M1 M0 GATE C/T M1 M0 TIMER 1 BIT TMOD.3/ TMOD.7 TMOD.2/ TMOD.6 SYMBOL GATE C/T TIMER 0 FUNCTION Gating control when set. Timer/Counter “n” is enabled only while “INTn” pin is high and “TRn” control pin is set. when cleared Timer “n” is enabled whenever “TRn” control bit is set. Timer or Counter Selector cleared for Timer operation (input from internal system clock.) Set for Counter operation (input from “Tn” input pin). M1 M0 OPERATING 0 0 8048 Timer: “TLn” serves as 5-bit prescaler. 0 1 16-bit Timer/Counter: “THn” and “TLn” are cascaded; there is no prescaler. 1 0 8-bit auto-reload Timer/Counter: “THn” holds a value which is to be reloaded into “TLn” each time it overflows. 1 1 (Timer 0) TL0 is an 8-bit Timer/Counter controlled by the standard Timer 0 control bits. TH0 is an 8-bit timer only controlled by Timer 1 control bits. 1 1 (Timer 1) Timer/Counter 1 stopped. SU01580 Figure 3. Timer/Counter 0/1 Mode Control (TMOD) Register ÷ d* OSC C/T = 0 TLn (5 Bits) THn (8 Bits) TFn Interrupt C/T = 1 Control Tn Pin TRn Timer n Gate bit INTn Pin *d = 6 in 6-clock mode; d = 12 in 12-clock mode. SU01618 Figure 4. Timer/Counter 0/1 Mode 0: 13-Bit Timer/Counter 2003 Sep 11 21 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM TCON Address = 88H Reset Value = 00H Bit Addressable 7 TF1 BIT TCON.7 SYMBOL TF1 TCON.6 TCON.5 TR1 TF0 TCON.4 TCON.3 TR0 IE1 TCON.2 IT1 TCON.1 IE0 TCON.0 IT0 6 5 4 3 2 1 0 TR1 TF0 TR0 IE1 IT1 IE0 IT0 FUNCTION Timer 1 overflow flag. Set by hardware on Timer/Counter overflow. Cleared by hardware when processor vectors to interrupt routine, or clearing the bit in software. Timer 1 Run control bit. Set/cleared by software to turn Timer/Counter on/off. Timer 0 overflow flag. Set by hardware on Timer/Counter overflow. Cleared by hardware when processor vectors to interrupt routine, or by clearing the bit in software. Timer 0 Run control bit. Set/cleared by software to turn Timer/Counter on/off. Interrupt 1 Edge flag. Set by hardware when external interrupt edge detected. Cleared when interrupt processed. Interrupt 1 type control bit. Set/cleared by software to specify falling edge/low level triggered external interrupts. Interrupt 0 Edge flag. Set by hardware when external interrupt edge detected. Cleared when interrupt processed. Interrupt 0 Type control bit. Set/cleared by software to specify falling edge/low level triggered external interrupts. SU01516 Figure 5. Timer/Counter 0/1 Control (TCON) Register ÷ d* OSC C/T = 0 TLn (8 Bits) TFn Interrupt C/T = 1 Control Tn Pin Reload TRn Timer n Gate bit THn (8 Bits) INTn Pin SU01619 *d = 6 in 6-clock mode; d = 12 in 12-clock mode. Figure 6. Timer/Counter 0/1 Mode 2: 8-Bit Auto-Reload 2003 Sep 11 22 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM ÷ d* OSC C/T = 0 TL0 (8 Bits) TF0 Interrupt TH0 (8 Bits) TF1 Interrupt C/T = 1 Control T0 Pin TR0 Timer 0 Gate bit INT0 Pin OSC ÷ d* Control TR1 *d = 6 in 6-clock mode; d = 12 in 12-clock mode. SU01620 Figure 7. Timer/Counter 0 Mode 3: Two 8-Bit Counters Counter Enable) which is located in the T2MOD register (see Figure 10). After reset, DCEN=0 which means Timer 2 will default to counting up. If DCEN is set, Timer 2 can count up or down depending on the value of the T2EX pin. TIMER 2 OPERATION Timer 2 Timer 2 is a 16-bit Timer/Counter which can operate as either an event timer or an event counter, as selected by C/T2 in the special function register T2CON (see Figure 8). Timer 2 has three operating modes: Capture, Auto-reload (up or down counting), and Baud Rate Generator, which are selected by bits in the T2CON as shown in Table 6. Figure 11 shows Timer 2 which will count up automatically since DCEN=0. In this mode there are two options selected by bit EXEN2 in T2CON register. If EXEN2=0, then Timer 2 counts up to 0FFFFH and sets the TF2 (Overflow Flag) bit upon overflow. This causes the Timer 2 registers to be reloaded with the 16-bit value in RCAP2L and RCAP2H. The values in RCAP2L and RCAP2H are preset by software. Capture Mode In the capture mode there are two options which are selected by bit EXEN2 in T2CON. If EXEN2=0, then timer 2 is a 16-bit timer or counter (as selected by C/T2 in T2CON) which, upon overflowing, sets bit TF2, the timer 2 overflow bit. This bit can be used to generate an interrupt (by enabling the Timer 2 interrupt bit in the IE register). If EXEN2=1, Timer 2 operates as described above, but with the added feature that a 1-to-0 transition at external input T2EX causes the current value in the Timer 2 registers, TL2 and TH2, to be captured into registers RCAP2L and RCAP2H, respectively. In addition, the transition at T2EX causes bit EXF2 in T2CON to be set, and EXF2 (like TF2) can generate an interrupt (which vectors to the same location as Timer 2 overflow interrupt. The Timer 2 interrupt service routine can interrogate TF2 and EXF2 to determine which event caused the interrupt). The capture mode is illustrated in Figure 9 (There is no reload value for TL2 and TH2 in this mode. Even when a capture event occurs from T2EX, the counter keeps on counting T2EX pin transitions or osc/12 (12-clock Mode) or osc/6 (6-clock Mode) pulses). If EXEN2=1, then a 16-bit reload can be triggered either by an overflow or by a 1-to-0 transition at input T2EX. This transition also sets the EXF2 bit. The Timer 2 interrupt, if enabled, can be generated when either TF2 or EXF2 are 1. In Figure 12 DCEN=1 which enables Timer 2 to count up or down. This mode allows pin T2EX to control the direction of count. When a logic 1 is applied at pin T2EX, Timer 2 will count up. Timer 2 will overflow at 0FFFFH and set the TF2 flag, which can then generate an interrupt, if the interrupt is enabled. This timer overflow also causes the 16-bit value in RCAP2L and RCAP2H to be reloaded into the timer registers TL2 and TH2. A logic 0 applied to pin T2EX causes Timer 2 to count down. The timer will underflow when TL2 and TH2 become equal to the value stored in RCAP2L and RCAP2H. A Timer 2 underflow sets the TF2 flag and causes 0FFFFH to be reloaded into the timer registers TL2 and TH2. The external flag EXF2 toggles when Timer 2 underflows or overflows. This EXF2 bit can be used as a 17th bit of resolution if needed. The EXF2 flag does not generate an interrupt in this mode of operation. Auto-Reload Mode (Up or Down Counter) In the 16-bit auto-reload mode, Timer 2 can be configured as either a timer or counter (C/T2 in T2CON), then programmed to count up or down. The counting direction is determined by bit DCEN (Down 2003 Sep 11 23 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Table 6. Timer 2 Operating Modes RCLK + TCLK CP/RL2 TR2 0 0 1 16-bit Auto-reload 0 1 1 16-bit Capture 1 X 1 Baud rate generator X X 0 (off) T2CON MODE Address = C8H Bit Addressable Reset Value = 00H 7 TF2 6 5 4 3 2 1 0 EXF2 RCLK TCLK EXEN2 TR2 C/T2 CP/RL2 Symbol Position Name and Significance TF2 T2CON.7 EXF2 T2CON.6 RCLK T2CON.5 TCLK T2CON.4 EXEN2 T2CON.3 TR2 C/T2 T2CON.2 T2CON.1 CP/RL2 T2CON.0 Timer 2 overflow flag set by a Timer 2 overflow and must be cleared by software. TF2 will not be set when either RCLK or TCLK = 1. Timer 2 external flag set when either a capture or reload is caused by a negative transition on T2EX and EXEN2 = 1. When Timer 2 interrupt is enabled, EXF2 = 1 will cause the CPU to vector to the Timer 2 interrupt routine. EXF2 must be cleared by software. EXF2 does not cause an interrupt in up/down counter mode (DCEN = 1). Receive clock flag. When set, causes the serial port to use Timer 2 overflow pulses for its receive clock in modes 1 and 3. RCLK = 0 causes Timer 1 overflow to be used for the receive clock. Transmit clock flag. When set, causes the serial port to use Timer 2 overflow pulses for its transmit clock in modes 1 and 3. TCLK = 0 causes Timer 1 overflows to be used for the transmit clock. Timer 2 external enable flag. When set, allows a capture or reload to occur as a result of a negative transition on T2EX if Timer 2 is not being used to clock the serial port. EXEN2 = 0 causes Timer 2 to ignore events at T2EX. Start/stop control for Timer 2. A logic 1 starts the timer. Timer or counter select. (Timer 2) 0 = Internal timer (OSC/12 in 12-clock mode or OSC/6 in 6-clock mode) 1 = External event counter (falling edge triggered). Capture/Reload flag. When set, captures will occur on negative transitions at T2EX if EXEN2 = 1. When cleared, auto-reloads will occur either with Timer 2 overflows or negative transitions at T2EX when EXEN2 = 1. When either RCLK = 1 or TCLK = 1, this bit is ignored and the timer is forced to auto-reload on Timer 2 overflow. SU01621 Figure 8. Timer/Counter 2 (T2CON) Control Register 2003 Sep 11 24 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM ÷ n* OSC C/T2 = 0 TL2 (8 bits) TH2 (8 bits) TF2 C/T2 = 1 T2 Pin Control TR2 Capture Transition Detector Timer 2 Interrupt RCAP2L RCAP2H T2EX Pin EXF2 Control EXEN2 SU01622 *n = 6 in 6-clock mode; n = 12 in 12-clock mode. Figure 9. Timer 2 in Capture Mode T2MOD Address = 0C9H Reset Value = XXXX XX00B Not Bit Addressable Symbol Position — * 7 6 5 4 3 2 1 0 — — — — — — T2OE DCEN Function Not implemented, reserved for future use.* T2OE T2MOD.1 DCEN T2MOD.0 Timer 2 Output Enable bit. Down Count Enable bit. When set, this allows Timer 2 to be configured as an up/down counter. User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features. In that case, the reset or inactive value of the new bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate. SU01519 Figure 10. Timer 2 Mode (T2MOD) Control Register 2003 Sep 11 25 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM ÷ n* OSC C/T2 = 0 TL2 (8-BITS) TH2 (8-BITS) C/T2 = 1 T2 Pin CONTROL TR2 RELOAD TRANSITION DETECTOR RCAP2L RCAP2H TF2 TIMER 2 INTERRUPT T2EX PIN EXF2 CONTROL *n = 6 in 6-clock mode; n = 12 in 12-clock mode. SU01623 EXEN2 Figure 11. Timer 2 in Auto-Reload Mode (DCEN = 0) (DOWN COUNTING RELOAD VALUE) FFH FFH TOGGLE EXF2 ÷ n* OSC C/T2 = 0 OVERFLOW TL2 TH2 TF2 INTERRUPT C/T2 = 1 T2 Pin CONTROL TR2 COUNT DIRECTION 1 = UP 0 = DOWN RCAP2L RCAP2H *n = 6 in 6-clock mode; n = 12 in 12-clock mode. (UP COUNTING RELOAD VALUE) Figure 12. Timer 2 Auto Reload Mode (DCEN = 1) 2003 Sep 11 26 T2EX PIN SU01624 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Timer 1 Overflow n = 1 in 6-clock mode n = 2 in 12-clock mode. ÷2 OSC “0” ÷n “1” C/T2 = 0 SMOD TL2 (8 bits) “1” TH2 (8 bits) “0” RCLK C/T2 = 1 T2 Pin Control ÷ 16 “1” TR2 Reload Transition Detector RCAP2L T2EX Pin EXF2 RCAP2H RX Clock “0” TCLK ÷ 16 TX Clock Timer 2 Interrupt Control EXEN2 Note availability of additional external interrupt. SU01625 Figure 13. Timer 2 in Baud Rate Generator Mode Modes 1 and 3 Baud Rates = Oscillator Frequency [n [65536 * (RCAP2H, RCAP2L)]] Baud Rate Generator Mode Bits TCLK and/or RCLK in T2CON (Table 6) allow the serial port transmit and receive baud rates to be derived from either Timer 1 or Timer 2. When TCLK= 0, Timer 1 is used as the serial port transmit baud rate generator. When TCLK= 1, Timer 2 is used as the serial port transmit baud rate generator. RCLK has the same effect for the serial port receive baud rate. With these two bits, the serial port can have different receive and transmit baud rates – one generated by Timer 1, the other by Timer 2. Where: n = 16 in 6-clock mode, 32 in 12-clock mode. (RCAP2H, RCAP2L)= The content of RCAP2H and RCAP2L taken as a 16-bit unsigned integer. The Timer 2 as a baud rate generator mode shown in Figure 13 is valid only if RCLK and/or TCLK = 1 in T2CON register. Note that a rollover in TH2 does not set TF2, and will not generate an interrupt. Thus, the Timer 2 interrupt does not have to be disabled when Timer 2 is in the baud rate generator mode. Also if the EXEN2 (T2 external enable flag) is set, a 1-to-0 transition in T2EX (Timer/counter 2 trigger input) will set EXF2 (T2 external flag) but will not cause a reload from (RCAP2H, RCAP2L) to (TH2,TL2). Therefore when Timer 2 is in use as a baud rate generator, T2EX can be used as an additional external interrupt, if needed. Figure 13 shows the Timer 2 in baud rate generation mode. The baud rate generation mode is like the auto-reload mode, in that a rollover in TH2 causes the Timer 2 registers to be reloaded with the 16-bit value in registers RCAP2H and RCAP2L, which are preset by software. The baud rates in modes 1 and 3 are determined by Timer 2’s overflow rate given below: Modes 1 and 3 Baud Rates + Timer 2 Overflow Rate 16 When Timer 2 is in the baud rate generator mode, one should not try to read or write TH2 and TL2. As a baud rate generator, Timer 2 is incremented every state time (osc/2) or asynchronously from pin T2; under these conditions, a read or write of TH2 or TL2 may not be accurate. The RCAP2 registers may be read, but should not be written to, because a write might overlap a reload and cause write and/or reload errors. The timer should be turned off (clear TR2) before accessing the Timer 2 or RCAP2 registers. The timer can be configured for either “timer” or “counter” operation. In many applications, it is configured for “timer” operation (C/T2=0). Timer operation is different for Timer 2 when it is being used as a baud rate generator. Usually, as a timer it would increment every machine cycle (i.e., 1/6 the oscillator frequency in 6-clock mode or 1/12 the oscillator frequency in 12-clock mode). As a baud rate generator, it increments at the oscillator frequency in 6-clock mode or at 1/2 the oscillator frequency in 12-clock mode. Thus the baud rate formula is as follows: 2003 Sep 11 Table 7 shows commonly used baud rates and how they can be obtained from Timer 2. 27 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Table 7. Timer 2 Generated Commonly Used Baud Rates Baud Rate Timer/Counter 2 Set-up Except for the baud rate generator mode, the values given for T2CON do not include the setting of the TR2 bit. Therefore, bit TR2 must be set, separately, to turn the timer on. See Table 8 for set-up of Timer 2 as a timer. Also see Table 9 for set-up of Timer 2 as a counter. Timer 2 12-clk mode 6-clk mode Osc Freq 375 K 9.6 K 4.8 K 2.4 K 1.2 K 300 110 300 110 750 K 19.2 K 9.6 K 4.8 K 2.4 K 600 220 600 220 12 MHz 12 MHz 12 MHz 12 MHz 12 MHz 12 MHz 12 MHz 6 MHz 6 MHz RCAP2H RCAP2L FF FF FF FF FE FB F2 FD F9 FF D9 B2 64 C8 1E AF 8F 57 Table 8. Timer 2 as a Timer T2CON Summary Of Baud Rate Equations Timer 2 is in baud rate generating mode. If Timer 2 is being clocked through pin T2(P1.0) the baud rate is: Baud Rate + Timer 2 Overflow Rate 16 MODE INTERNAL CONTROL (Note 1) EXTERNAL CONTROL (Note 2) 16-bit Auto-Reload 00H 08H 16-bit Capture 01H 09H Baud rate generator receive and transmit same baud rate 34H 36H Receive only 24H 26H Transmit only 14H 16H Table 9. Timer 2 as a Counter If Timer 2 is being clocked internally, the baud rate is: Baud Rate + [n TMOD f OSC [65536 * (RCAP2H, RCAP2L)]] MODE Where: n = 16 in 6-clock mode, 32 in 12-clock mode. INTERNAL CONTROL (Note 1) EXTERNAL CONTROL (Note 2) 16-bit 02H 0AH Auto-Reload 03H 0BH fOSC= Oscillator Frequency NOTES: 1. Capture/reload occurs only on timer/counter overflow. 2. Capture/reload occurs on timer/counter overflow and a 1-to-0 transition on T2EX (P1.1) pin except when Timer 2 is used in the baud rate generator mode. To obtain the reload value for RCAP2H and RCAP2L, the above equation can be rewritten as: RCAP2H, RCAP2L + 65536 * 2003 Sep 11 ǒ n Ǔ f OSC Baud Rate 28 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM The slaves that weren’t being addressed leave their SM2s set and go on about their business, ignoring the coming data bytes. FULL-DUPLEX ENHANCED UART Standard UART operation SM2 has no effect in Mode 0, and in Mode 1 can be used to check the validity of the stop bit. In a Mode 1 reception, if SM2 = 1, the receive interrupt will not be activated unless a valid stop bit is received. The serial port is full duplex, meaning it can transmit and receive simultaneously. It is also receive-buffered, meaning it can commence reception of a second byte before a previously received byte has been read from the register. (However, if the first byte still hasn’t been read by the time reception of the second byte is complete, one of the bytes will be lost.) The serial port receive and transmit registers are both accessed at Special Function Register SBUF. Writing to SBUF loads the transmit register, and reading SBUF accesses a physically separate receive register. Serial Port Control Register The serial port control and status register is the Special Function Register SCON, shown in Figure 14. This register contains not only the mode selection bits, but also the 9th data bit for transmit and receive (TB8 and RB8), and the serial port interrupt bits (TI and RI). The serial port can operate in 4 modes: Mode 0: Serial data enters and exits through RxD. TxD outputs the shift clock. 8 bits are transmitted/received (LSB first). The baud rate is fixed at 1/12 the oscillator frequency (in 12-clock mode) or 1/6 the oscillator frequency (in 6-clock mode). Mode 1: 10 bits are transmitted (through TxD) or received (through RxD): a start bit (0), 8 data bits (LSB first), and a stop bit (1). On receive, the stop bit goes into RB8 in Special Function Register SCON. The baud rate is variable. Mode 2: Mode 3: Baud Rates The baud rate in Mode 0 is fixed: Mode 0 Baud Rate = Oscillator Frequency / 12 (in 12-clock mode) or / 6 (in 6-clock mode). The baud rate in Mode 2 depends on the value of bit SMOD in Special Function Register PCON. If SMOD = 0 (which is the value on reset), and the port pins in 12-clock mode, the baud rate is 1/64 the oscillator frequency. If SMOD = 1, the baud rate is 1/32 the oscillator frequency. In 6-clock mode, the baud rate is 1/32 or 1/16 the oscillator frequency, respectively. Mode 2 Baud Rate = 2 SMOD n 11 bits are transmitted (through TxD) or received (through RxD): start bit (0), 8 data bits (LSB first), a programmable 9th data bit, and a stop bit (1). On Transmit, the 9th data bit (TB8 in SCON) can be assigned the value of 0 or 1. Or, for example, the parity bit (P, in the PSW) could be moved into TB8. On receive, the 9th data bit goes into RB8 in Special Function Register SCON, while the stop bit is ignored. The baud rate is programmable to either 1/32 or 1/64 the oscillator frequency (in 12-clock mode) or 1/16 or 1/32 the oscillator frequency (in 6-clock mode). Where: n = 64 in 12-clock mode, 32 in 6-clock mode The baud rates in Modes 1 and 3 are determined by the Timer 1 or Timer 2 overflow rate. Using Timer 1 to Generate Baud Rates When Timer 1 is used as the baud rate generator (T2CON.RCLK = 0, T2CON.TCLK = 0), the baud rates in Modes 1 and 3 are determined by the Timer 1 overflow rate and the value of SMOD as follows: 11 bits are transmitted (through TxD) or received (through RxD): a start bit (0), 8 data bits (LSB first), a programmable 9th data bit, and a stop bit (1). In fact, Mode 3 is the same as Mode 2 in all respects except baud rate. The baud rate in Mode 3 is variable. Mode 1, 3 Baud Rate = 2 SMOD n (Timer 1 Overflow Rate) Where: In all four modes, transmission is initiated by any instruction that uses SBUF as a destination register. Reception is initiated in Mode 0 by the condition RI = 0 and REN = 1. Reception is initiated in the other modes by the incoming start bit if REN = 1. n = 32 in 12-clock mode, 16 in 6-clock mode The Timer 1 interrupt should be disabled in this application. The Timer itself can be configured for either “timer” or “counter” operation, and in any of its 3 running modes. In the most typical applications, it is configured for “timer” operation, in the auto-reload mode (high nibble of TMOD = 0010B). In that case the baud rate is given by the formula: Multiprocessor Communications Modes 2 and 3 have a special provision for multiprocessor communications. In these modes, 9 data bits are received. The 9th one goes into RB8. Then comes a stop bit. The port can be programmed such that when the stop bit is received, the serial port interrupt will be activated only if RB8 = 1. This feature is enabled by setting bit SM2 in SCON. A way to use this feature in multiprocessor systems is as follows: Mode 1, 3 Baud Rate = 2 SMOD n Oscillator Frequency 12 [256–(TH1)] Where: When the master processor wants to transmit a block of data to one of several slaves, it first sends out an address byte which identifies the target slave. An address byte differs from a data byte in that the 9th bit is 1 in an address byte and 0 in a data byte. With SM2 = 1, no slave will be interrupted by a data byte. An address byte, however, will interrupt all slaves, so that each slave can examine the received byte and see if it is being addressed. The addressed slave will clear its SM2 bit and prepare to receive the data bytes that will be coming. 2003 Sep 11 (Oscillator Frequency) n = 32 in 12-clock mode, 16 in 6-clock mode One can achieve very low baud rates with Timer 1 by leaving the Timer 1 interrupt enabled, and configuring the Timer to run as a 16-bit timer (high nibble of TMOD = 0001B), and using the Timer 1 interrupt to do a 16-bit software reload. Figure 15 lists various commonly used baud rates and how they can be obtained from Timer 1. 29 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM SCON Address = 98H Bit Addressable Reset Value = 00H 7 6 5 4 3 2 1 0 SM0 SM1 SM2 REN TB8 RB8 TI RI Where SM0, SM1 specify the serial port mode, as follows: SM0 0 0 1 1 SM1 0 1 0 1 Mode 0 1 2 3 Description shift register 8-bit UART 9-bit UART 9-bit UART Baud Rate fOSC/12 (12-clock mode) or fOSC/6 (6-clock mode) variable fOSC/64 or fOSC/32 (12-clock mode) or fOSC/32 or fOSC/16 (6-clock mode) variable SM2 Enables the multiprocessor communication feature in Modes 2 and 3. In Mode 2 or 3, if SM2 is set to 1, then Rl will not be activated if the received 9th data bit (RB8) is 0. In Mode 1, if SM2=1 then RI will not be activated if a valid stop bit was not received. In Mode 0, SM2 should be 0. REN Enables serial reception. Set by software to enable reception. Clear by software to disable reception. TB8 The 9th data bit that will be transmitted in Modes 2 and 3. Set or clear by software as desired. RB8 In Modes 2 and 3, is the 9th data bit that was received. In Mode 1, it SM2=0, RB8 is the stop bit that was received. In Mode 0, RB8 is not used. TI Transmit interrupt flag. Set by hardware at the end of the 8th bit time in Mode 0, or at the beginning of the stop bit in the other modes, in any serial transmission. Must be cleared by software. RI Receive interrupt flag. Set by hardware at the end of the 8th bit time in Mode 0, or halfway through the stop bit time in the other modes, in any serial reception (except see SM2). Must be cleared by software. SU01626 Figure 14. Serial Port Control (SCON) Register Timer 1 Baud Rate Mode 12-clock mode 6-clock mode Mode 0 Max Mode 2 Max Mode 1, 3 Max Mode 1, 3 1.67 MHz 625 k 104.2 k 19.2 k 9.6 k 4.8 k 2.4 k 1.2 k 137.5 110 110 3.34 MHz 1250 k 208.4 k 38.4 k 19.2 k 9.6 k 4.8 k 2.4 k 275 220 220 fOSC SMOD 20 MHz 20 MHz 20 MHz 11.059 MHz 11.059 MHz 11.059 MHz 11.059 MHz 11.059 MHz 11.986 MHz 6 MHz 12 MHz X 1 1 1 0 0 0 0 0 0 0 C/T Mode Reload Value X X 0 0 0 0 0 0 0 0 0 X X 2 2 2 2 2 2 2 2 1 X X FFH FDH FDH FAH F4H E8H 1DH 72H FEEBH Figure 15. Timer 1 Generated Commonly Used Baud Rates More About Mode 0 Serial data enters and exits through RxD. TxD outputs the shift clock. 8 bits are transmitted/received: 8 data bits (LSB first). The baud rate is fixed at 1/12 the oscillator frequency (12-clock mode) or 1/6 the oscillator frequency (6-clock mode). S6P2 of every machine cycle in which SEND is active, the contents of the transmit shift are shifted to the right one position. As data bits shift out to the right, zeros come in from the left. When the MSB of the data byte is at the output position of the shift register, then the 1 that was initially loaded into the 9th position, is just to the left of the MSB, and all positions to the left of that contain zeros. This condition flags the TX Control block to do one last shift and then deactivate SEND and set T1. Both of these actions occur at S1P1 of the 10th machine cycle after “write to SBUF.” Figure 16 shows a simplified functional diagram of the serial port in Mode 0, and associated timing. Transmission is initiated by any instruction that uses SBUF as a destination register. The “write to SBUF” signal at S6P2 also loads a 1 into the 9th position of the transmit shift register and tells the TX Control block to commence a transmission. The internal timing is such that one full machine cycle will elapse between “write to SBUF” and activation of SEND. Reception is initiated by the condition REN = 1 and R1 = 0. At S6P2 of the next machine cycle, the RX Control unit writes the bits 11111110 to the receive shift register, and in the next clock phase activates RECEIVE. RECEIVE enable SHIFT CLOCK to the alternate output function line of P3.1. SHIFT CLOCK makes transitions at S3P1 and S6P1 of every machine cycle. At S6P2 of every machine cycle in which RECEIVE is active, the contents of the receive shift register are SEND enables the output of the shift register to the alternate output function line of P3.0 and also enable SHIFT CLOCK to the alternate output function line of P3.1. SHIFT CLOCK is low during S3, S4, and S5 of every machine cycle, and high during S6, S1, and S2. At 2003 Sep 11 30 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM shifted to the left one position. The value that comes in from the right is the value that was sampled at the P3.0 pin at S5P2 of the same machine cycle. whether the above conditions are met or not, the unit goes back to looking for a 1-to-0 transition in RxD. More About Modes 2 and 3 Eleven bits are transmitted (through TxD), or received (through RxD): a start bit (0), 8 data bits (LSB first), a programmable 9th data bit, and a stop bit (1). On transmit, the 9th data bit (TB8) can be assigned the value of 0 or 1. On receive, the 9the data bit goes into RB8 in SCON. The baud rate is programmable to either 1/32 or 1/64 (12-clock mode) or 1/16 or 1/32 the oscillator frequency (6-clock mode) the oscillator frequency in Mode 2. Mode 3 may have a variable baud rate generated from Timer 1 or Timer 2. As data bits come in from the right, 1s shift out to the left. When the 0 that was initially loaded into the rightmost position arrives at the leftmost position in the shift register, it flags the RX Control block to do one last shift and load SBUF. At S1P1 of the 10th machine cycle after the write to SCON that cleared RI, RECEIVE is cleared as RI is set. More About Mode 1 Ten bits are transmitted (through TxD), or received (through RxD): a start bit (0), 8 data bits (LSB first), and a stop bit (1). On receive, the stop bit goes into RB8 in SCON. In the 80C51 the baud rate is determined by the Timer 1 or Timer 2 overflow rate. Figures 18 and 19 show a functional diagram of the serial port in Modes 2 and 3. The receive portion is exactly the same as in Mode 1. The transmit portion differs from Mode 1 only in the 9th bit of the transmit shift register. Figure 17 shows a simplified functional diagram of the serial port in Mode 1, and associated timings for transmit receive. Transmission is initiated by any instruction that uses SBUF as a destination register. The “write to SBUF” signal also loads TB8 into the 9th bit position of the transmit shift register and flags the TX Control unit that a transmission is requested. Transmission commences at S1P1 of the machine cycle following the next rollover in the divide-by-16 counter. (Thus, the bit times are synchronized to the divide-by-16 counter, not to the “write to SBUF” signal.) Transmission is initiated by any instruction that uses SBUF as a destination register. The “write to SBUF” signal also loads a 1 into the 9th bit position of the transmit shift register and flags the TX Control unit that a transmission is requested. Transmission actually commences at S1P1 of the machine cycle following the next rollover in the divide-by-16 counter. (Thus, the bit times are synchronized to the divide-by-16 counter, not to the “write to SBUF” signal.) The transmission begins with activation of SEND, which puts the start bit at TxD. One bit time later, DATA is activated, which enables the output bit of the transmit shift register to TxD. The first shift pulse occurs one bit time after that. The first shift clocks a 1 (the stop bit) into the 9th bit position of the shift register. Thereafter, only zeros are clocked in. Thus, as data bits shift out to the right, zeros are clocked in from the left. When TB8 is at the output position of the shift register, then the stop bit is just to the left of TB8, and all positions to the left of that contain zeros. This condition flags the TX Control unit to do one last shift and then deactivate SEND and set TI. This occurs at the 11th divide-by-16 rollover after “write to SUBF.” The transmission begins with activation of SEND which puts the start bit at TxD. One bit time later, DATA is activated, which enables the output bit of the transmit shift register to TxD. The first shift pulse occurs one bit time after that. As data bits shift out to the right, zeros are clocked in from the left. When the MSB of the data byte is at the output position of the shift register, then the 1 that was initially loaded into the 9th position is just to the left of the MSB, and all positions to the left of that contain zeros. This condition flags the TX Control unit to do one last shift and then deactivate SEND and set TI. This occurs at the 10th divide-by-16 rollover after “write to SBUF.” Reception is initiated by a detected 1-to-0 transition at RxD. For this purpose RxD is sampled at a rate of 16 times whatever baud rate has been established. When a transition is detected, the divide-by-16 counter is immediately reset, and 1FFH is written to the input shift register. Reception is initiated by a detected 1-to-0 transition at RxD. For this purpose RxD is sampled at a rate of 16 times whatever baud rate has been established. When a transition is detected, the divide-by-16 counter is immediately reset, and 1FFH is written into the input shift register. Resetting the divide-by-16 counter aligns its rollovers with the boundaries of the incoming bit times. At the 7th, 8th, and 9th counter states of each bit time, the bit detector samples the value of R-D. The value accepted is the value that was seen in at least 2 of the 3 samples. If the value accepted during the first bit time is not 0, the receive circuits are reset and the unit goes back to looking for another 1-to-0 transition. If the start bit proves valid, it is shifted into the input shift register, and reception of the rest of the frame will proceed. The 16 states of the counter divide each bit time into 16ths. At the 7th, 8th, and 9th counter states of each bit time, the bit detector samples the value of RxD. The value accepted is the value that was seen in at least 2 of the 3 samples. This is done for noise rejection. If the value accepted during the first bit time is not 0, the receive circuits are reset and the unit goes back to looking for another 1-to-0 transition. This is to provide rejection of false start bits. If the start bit proves valid, it is shifted into the input shift register, and reception of the rest of the frame will proceed. As data bits come in from the right, 1s shift out to the left. When the start bit arrives at the leftmost position in the shift register (which in Modes 2 and 3 is a 9-bit register), it flags the RX Control block to do one last shift, load SBUF and RB8, and set RI. The signal to load SBUF and RB8, and to set RI, will be generated if, and only if, the following conditions are met at the time the final shift pulse is generated. 1. RI = 0, and 2. Either SM2 = 0, or the received 9th data bit = 1. As data bits come in from the right, 1s shift out to the left. When the start bit arrives at the leftmost position in the shift register (which in mode 1 is a 9-bit register), it flags the RX Control block to do one last shift, load SBUF and RB8, and set RI. The signal to load SBUF and RB8, and to set RI, will be generated if, and only if, the following conditions are met at the time the final shift pulse is generated.: 1. R1 = 0, and 2. Either SM2 = 0, or the received stop bit = 1. If either of these conditions is not met, the received frame is irretrievably lost, and RI is not set. If both conditions are met, the received 9th data bit goes into RB8, and the first 8 data bits go into SBUF. One bit time later, whether the above conditions were met or not, the unit goes back to looking for a 1-to-0 transition at the RxD input. If either of these two conditions is not met, the received frame is irretrievably lost. If both conditions are met, the stop bit goes into RB8, the 8 data bits go into SBUF, and RI is activated. At this time, 2003 Sep 11 31 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM 80C51 Internal Bus Write to SBUF S D Q RxD P3.0 Alt Output Function SBUF CL Zero Detector Start Shift TX Control S6 T1 TX Clock Send Serial Port Interrupt R1 RX Clock Receive RX Control REN RI Start 1 1 1 TxD P3.1 Alt Output Function Shift Clock Shift 1 1 1 1 0 MSB LSB RxD P3.0 Alt Input Function Input Shift Register Shift Load SBUF LSB MSB SBUF Read SBUF 80C51 Internal Bus S4 . . S1 . . . . S6 S1 . . . . S6 S1 . . . . S6 S1 . . . . S6 S1 . . . . S6 S1 . . . . S6 S1 . . . . S6 S1 . . . . S6 S1 . . . . S6 S1 . . . . S6 S1 ALE Write to SBUF S6P2 Send Shift Transmit RxD (Data Out) D0 D1 D2 D3 D4 D5 D6 D7 TxD (Shift Clock) S3P1 TI S6P1 Write to SCON (Clear RI) RI Receive Shift RxD (Data In) Receive D0 D1 D2 D3 D4 D5 D6 D7 S5P2 TxD (Shift Clock) SU00539 Figure 16. Serial Port Mode 0 2003 Sep 11 32 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Timer 1 Overflow 80C51 Internal Bus TB8 ÷2 SMOD = 0 SMOD = 1 Write to SBUF S D Q SBUF TxD CL Zero Detector Start Data Shift TX Control ÷ 16 T1 Send RX Clock RI Load SBUF TX Clock Serial Port Interrupt ÷ 16 Sample RX Control 1-to-0 Transition Detector Shift Start 1FFH Bit Detector Input Shift Register (9 Bits) Shift RxD Load SBUF SBUF Read SBUF 80C51 Internal Bus TX Clock Write to SBUF Send Data S1P1 Transmit Shift TxD Start Bit D0 D1 D2 D3 D4 D5 D6 D7 Stop Bit D0 D1 D2 D3 D4 D5 D6 D7 Stop Bit TI ÷ 16 Reset RX Clock RxD Bit Detector Sample Times Start Bit Receive Shift RI SU00540 Figure 17. Serial Port Mode 1 2003 Sep 11 33 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM 80C51 Internal Bus TB8 Write to SBUF S D Phase 2 Clock (1/2 fOSC in 12-clock mode; fOSC in 6-clock mode) Q SBUF TxD CL Zero Detector Mode 2 Start ÷ 16 SMOD = 1 Stop Bit Gen. TX Control TX Clock Shift Data T1 Send R1 Load SBUF Serial Port Interrupt ÷2 SMOD = 0 (SMOD is PCON.7) ÷ 16 RX Clock Sample RX Control 1-to-0 Transition Detector Shift Start 1FFH Bit Detector Input Shift Register (9 Bits) Shift RxD Load SBUF SBUF Read SBUF 80C51 Internal Bus TX Clock Write to SBUF Send Data S1P1 Transmit Shift TxD Start Bit D0 D1 D2 D3 D4 D5 D6 D7 TB8 D0 D1 D2 D3 D4 D5 D6 D7 RB8 Stop Bit TI Stop Bit Gen. ÷ 16 Reset RX Clock RxD Bit Detector Sample Times Start Bit Stop Bit Receive Shift RI SU01627 Figure 18. Serial Port Mode 2 2003 Sep 11 34 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Timer 1 Overflow 80C51 Internal Bus TB8 Write to SBUF ÷2 SMOD = 0 SMOD = 1 S D Q SBUF TxD CL Zero Detector Start Data Shift TX Control ÷ 16 TX Clock T1 Send R1 Load SBUF Serial Port Interrupt ÷ 16 RX Clock Sample RX Control 1-to-0 Transition Detector Shift Start 1FFH Bit Detector Input Shift Register (9 Bits) Shift RxD Load SBUF SBUF Read SBUF 80C51 Internal Bus TX Clock Write to SBUF Send Data S1P1 Transmit Shift TxD Start Bit D0 D1 D2 D3 D4 D5 D6 D7 TB8 D0 D1 D2 D3 D4 D5 D6 D7 RB8 Stop Bit TI Stop Bit Gen. RX Clock RxD Bit Detector Sample Times ÷ 16 Reset Start Bit Stop Bit Receive Shift RI SU00542 Figure 19. Serial Port Mode 3 2003 Sep 11 35 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Slave 1 Enhanced UART operation In addition to the standard operation modes, the UART can perform framing error detect by looking for missing stop bits, and automatic address recognition. The UART also fully supports multiprocessor communication. In a more complex system the following could be used to select slaves 1 and 2 while excluding slave 0: Automatic Address Recognition Automatic Address Recognition is a feature which allows the UART to recognize certain addresses in the serial bit stream by using hardware to make the comparisons. This feature saves a great deal of software overhead by eliminating the need for the software to examine every serial address which passes by the serial port. This feature is enabled by setting the SM2 bit in SCON. In the 9 bit UART modes, mode 2 and mode 3, the Receive Interrupt flag (RI) will be automatically set when the received byte contains either the “Given” address or the “Broadcast” address. The 9 bit mode requires that the 9th information bit is a 1 to indicate that the received information is an address and not data. Automatic address recognition is shown in Figure 22. Mode 0 is the Shift Register mode and SM2 is ignored. Using the Automatic Address Recognition feature allows a master to selectively communicate with one or more slaves by invoking the Given slave address or addresses. All of the slaves may be contacted by using the Broadcast address. Two special Function Registers are used to define the slave’s address, SADDR, and the address mask, SADEN. SADEN is used to define which bits in the SADDR are to be used and which bits are “don’t care”. The SADEN mask can be logically ANDed with the SADDR to create the “Given” address which the master will use for addressing each of the slaves. Use of the Given address allows multiple slaves to be recognized while excluding others. The following examples will help to show the versatility of this scheme: 2003 Sep 11 Slave 0 SADDR = SADEN = Given = 1100 0000 1111 1001 1100 0XX0 Slave 1 SADDR = SADEN = Given = 1110 0000 1111 1010 1110 0X0X Slave 2 SADDR = SADEN = Given = 1110 0000 1111 1100 1110 00XX In the above example the differentiation among the 3 slaves is in the lower 3 address bits. Slave 0 requires that bit 0 = 0 and it can be uniquely addressed by 1110 0110. Slave 1 requires that bit 1 = 0 and it can be uniquely addressed by 1110 and 0101. Slave 2 requires that bit 2 = 0 and its unique address is 1110 0011. To select Slaves 0 and 1 and exclude Slave 2 use address 1110 0100, since it is necessary to make bit 2 = 1 to exclude slave 2. The 8 bit mode is called Mode 1. In this mode the RI flag will be set if SM2 is enabled and the information received has a valid stop bit following the 8 address bits and the information is either a Given or Broadcast address. SADDR = SADEN = Given = 1100 0000 1111 1110 1100 000X In the above example SADDR is the same and the SADEN data is used to differentiate between the two slaves. Slave 0 requires a 0 in bit 0 and it ignores bit 1. Slave 1 requires a 0 in bit 1 and bit 0 is ignored. A unique address for Slave 0 would be 1100 0010 since slave 1 requires a 0 in bit 1. A unique address for slave 1 would be 1100 0001 since a 1 in bit 0 will exclude slave 0. Both slaves can be selected at the same time by an address which has bit 0 = 0 (for slave 0) and bit 1 = 0 (for slave 1). Thus, both could be addressed with 1100 0000. When used for framing error detect the UART looks for missing stop bits in the communication. A missing bit will set the FE bit in the SCON register. The FE bit shares the SCON.7 bit with SM0 and the function of SCON.7 is determined by PCON.6 (SMOD0) (see Figure 20). If SMOD0 is set then SCON.7 functions as FE. SCON.7 functions as SM0 when SMOD0 is cleared. When used as FE SCON.7 can only be cleared by software. Refer to Figure 21. Slave 0 SADDR = SADEN = Given = The Broadcast Address for each slave is created by taking the logical OR of SADDR and SADEN. Zeros in this result are trended as don’t-cares. In most cases, interpreting the don’t-cares as ones, the broadcast address will be FF hexadecimal. Upon reset SADDR (SFR address 0A9H) and SADEN (SFR address 0B9H) are leaded with 0s. This produces a given address of all “don’t cares” as well as a Broadcast address of all “don’t cares”. This effectively disables the Automatic Addressing mode and allows the microcontroller to use standard 80C51 type UART drivers which do not make use of this feature. 1100 0000 1111 1101 1100 00X0 36 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM SCON Address = 98H Reset Value = 0000 0000B Bit Addressable 7 6 5 4 3 2 1 0 SM0/FE SM1 SM2 REN TB8 RB8 Tl Rl (SMOD0 = 0/1)* Symbol Position Function FE SCON.7 Framing Error bit. This bit is set by the receiver when an invalid stop bit is detected. The FE bit is not cleared by valid frames but should be cleared by software. The SMOD0 bit must be set to enable access to the FE bit.* SM0 SCON.7 Serial Port Mode Bit 0, (SMOD0 must = 0 to access bit SM0) SM1 SCON.6 Serial Port Mode Bit 1 SM0 SM1 Mode Description Baud Rate** 0 0 1 0 1 0 0 1 2 shift register 8-bit UART 9-bit UART 1 1 3 9-bit UART fOSC/12 (12-clk mode) or fOSC/6 (6-clk mode) variable fOSC/64 or fOSC/32 or fOSC/16 (6-clock mode) or fOSC/32 (12-clock mode) variable SM2 SCON.5 Enables the Automatic Address Recognition feature in Modes 2 or 3. If SM2 = 1 then Rl will not be set unless the received 9th data bit (RB8) is 1, indicating an address, and the received byte is a Given or Broadcast Address. In Mode 1, if SM2 = 1 then Rl will not be activated unless a valid stop bit was received, and the received byte is a Given or Broadcast Address. In Mode 0, SM2 should be 0. REN SCON.4 Enables serial reception. Set by software to enable reception. Clear by software to disable reception. TB8 SCON.3 The 9th data bit that will be transmitted in Modes 2 and 3. Set or clear by software as desired. RB8 SCON.2 In modes 2 and 3, the 9th data bit that was received. In Mode 1, if SM2 = 0, RB8 is the stop bit that was received. In Mode 0, RB8 is not used. Tl SCON.1 Transmit interrupt flag. Set by hardware at the end of the 8th bit time in Mode 0, or at the beginning of the stop bit in the other modes, in any serial transmission. Must be cleared by software. Rl SCON.0 Receive interrupt flag. Set by hardware at the end of the 8th bit time in Mode 0, or halfway through the stop bit time in the other modes, in any serial reception (except see SM2). Must be cleared by software. NOTES: *SMOD0 is located at PCON.6. **fOSC = oscillator frequency SU01628 Figure 20. SCON: Serial Port Control Register 2003 Sep 11 37 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM D0 D1 D2 D3 D4 D5 D6 D7 D8 DATA BYTE START BIT ONLY IN MODE 2, 3 STOP BIT SET FE BIT IF STOP BIT IS 0 (FRAMING ERROR) SM0 TO UART MODE CONTROL SM0 / FE SM1 SM2 REN SMOD1 SMOD0 – POF TB8 GF1 RB8 TI GF0 PD RI SCON (98H) IDL PCON (87H) 0 : SCON.7 = SM0 1 : SCON.7 = FE SU01191 Figure 21. UART Framing Error Detection D0 D1 D2 D3 D4 SM0 SM1 1 1 1 0 D5 SM2 1 D6 D7 D8 REN TB8 RB8 1 X TI RI SCON (98H) RECEIVED ADDRESS D0 TO D7 COMPARATOR PROGRAMMED ADDRESS IN UART MODE 2 OR MODE 3 AND SM2 = 1: INTERRUPT IF REN=1, RB8=1 AND “RECEIVED ADDRESS” = “PROGRAMMED ADDRESS” – WHEN OWN ADDRESS RECEIVED, CLEAR SM2 TO RECEIVE DATA BYTES – WHEN ALL DATA BYTES HAVE BEEN RECEIVED: SET SM2 TO WAIT FOR NEXT ADDRESS. SU00045 Figure 22. UART Multiprocessor Communication, Automatic Address Recognition 2003 Sep 11 38 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM Priority Level Structure Each interrupt source can also be individually programmed to one of four priority levels by setting or clearing bits in Special Function Registers IP (Figure 25) and IPH (Figure 26). A lower-priority interrupt can itself be interrupted by a higher-priority interrupt, but not by another interrupt of the same level. A high-priority level 3 interrupt can’t be interrupted by any other interrupt source. Interrupt Priority Structure 0 INT0 IT0 IE0 1 If two request of different priority levels are received simultaneously, the request of higher priority level is serviced. If requests of the same priority level are received simultaneously, an internal polling sequence determines which request is serviced. Thus within each priority level there is a second priority structure determined by the polling sequence as follows: TF0 0 IT1 INT1 IE1 Interrupt Sources 1 Source 1. IE0 (External Int 0) 2. TF0 (Timer 0) 3. IE1 (External Int 1) 4. TF1 (Timer 1) 5. RI+TI (UART) 6. TF2, EXF2 (Timer 2) TF1 TI RI TF2, EXF2 Priority Within Level (highest) (lowest) SU01521 Note that the “priority within level” structure is only used to resolve simultaneous requests of the same priority level. Figure 23. Interrupt Sources The IP and IPH registers contain a number of unimplemented bits. User software should not write 1s to these positions, since they may be used in other 80C51 Family products. Interrupts The devices described in this data sheet provide six interrupt sources. These are shown in Figure 23. The External Interrupts INT0 and INT1 can each be either level-activated or transition-activated, depending on bits IT0 and IT1 in Register TCON. The flags that actually generate these interrupts are bits IE0 and IE1 in TCON. When an external interrupt is generated, the flag that generated it is cleared by the hardware when the service routine is vectored to only if the interrupt was transition-activated. If the interrupt was level-activated, then the external requesting source is what controls the request flag, rather than the on-chip hardware. How Interrupts Are Handled The interrupt flags are sampled at S5P2 of every machine cycle. The samples are polled during the following machine cycle. If one of the flags was in a set condition at S5P2 of the preceding cycle, the polling cycle will find it and the interrupt system will generate an LCALL to the appropriate service routine, provided this hardware-generated LCALL is not blocked by any of the following conditions: 1. An interrupt of equal or higher priority level is already in progress. 2. The current (polling) cycle is not the final cycle in the execution of the instruction in progress. 3. The instruction in progress is RETI or any write to the IE or IP registers. The Timer 0 and Timer 1 Interrupts are generated by TF0 and TF1, which are set by a rollover in their respective Timer/Counter registers (except see Timer 0 in Mode 3). When a timer interrupt is generated, the flag that generated it is cleared by the on-chip hardware when the service routine is vectored to. Any of these three conditions will block the generation of the LCALL to the interrupt service routine. Condition 2 ensures that the instruction in progress will be completed before vectoring to any service routine. Condition 3 ensures that if the instruction in progress is RETI or any access to IE or IP, then at least one more instruction will be executed before any interrupt is vectored to. The Serial Port Interrupt is generated by the logical OR of RI and TI. Neither of these flags is cleared by hardware when the service routine is vectored to. In fact, the service routine will normally have to determine whether it was RI or TI that generated the interrupt, and the bit will have to be cleared in software. All of the bits that generate interrupts can be set or cleared by software, with the same result as though it had been set or cleared by hardware. That is, interrupts can be generated or pending interrupts can be canceled in software. The polling cycle is repeated with each machine cycle, and the values polled are the values that were present at S5P2 of the previous machine cycle. Note that if an interrupt flag is active but not being responded to for one of the above conditions, if the flag is not still active when the blocking condition is removed, the denied interrupt will not be serviced. In other words, the fact that the interrupt flag was once active but not serviced is not remembered. Every polling cycle is new. Each of these interrupt sources can be individually enabled or disabled by setting or clearing a bit in Special Function Register IE (Figure 24). IE also contains a global disable bit, EA, which disables all interrupts at once. 2003 Sep 11 39 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM IE Address = 0A8H Reset Value = 0X000000B Bit Addressable 7 6 5 4 3 2 1 0 EA — ET2 ES ET1 EX1 ET0 EX0 Enable Bit = 1 enables the interrupt. Enable Bit = 0 disables it. BIT IE.7 SYMBOL EA IE.6 IE.5 IE.4 IE.3 IE.2 IE.1 IE.0 — ET2 ES ET1 EX1 ET0 EX0 FUNCTION Global disable bit. If EA = 0, all interrupts are disabled. If EA = 1, each interrupt can be individually enabled or disabled by setting or clearing its enable bit. Not implemented. Reserved for future use. Timer 2 interrupt enable bit. Serial Port interrupt enable bit. Timer 1 interrupt enable bit. External interrupt 1 enable bit. Timer 0 interrupt enable bit. External interrupt 0 enable bit. SU01522 Figure 24. Interrupt Enable (IE) Register IP Address = 0B8H Reset Value = xx000000B Bit Addressable 7 6 5 4 3 2 1 0 — — PT2 PS PT1 PX1 PT0 PX0 Priority Bit = 1 assigns higher priority Priority Bit = 0 assigns lower priority BIT IP.7 IP.6 IP.5 IP.4 IP.3 IP.2 IP.1 IP.0 SYMBOL — — PT2 PS PT1 PX1 PT0 PX0 FUNCTION Not implemented, reserved for future use. Not implemented, reserved for future use. Timer 2 interrupt priority bit. Serial Port interrupt priority bit. Timer 1 interrupt priority bit. External interrupt 1 priority bit. Timer 0 interrupt priority bit. External interrupt 0 priority bit. SU01523 Figure 25. Interrupt Priority (IP) Register IPH Address = B7H Bit Addressable Reset Value = xx000000B 7 6 5 4 3 2 1 0 — — PT2H PSH PT1H PX1H PT0H PX0H Priority Bit = 1 assigns higher priority Priority Bit = 0 assigns lower priority BIT IPH.7 IPH.6 IPH.5 IPH.4 IPH.3 IPH.2 IPH.1 IPH.0 SYMBOL — — PT2H PSH PT1H PX1H PT0H PX0H FUNCTION Not implemented, reserved for future use. Not implemented, reserved for future use. Timer 2 interrupt priority bit high. Serial Port interrupt priority bit high. Timer 1 interrupt priority bit high. External interrupt 1 priority bit high. Timer 0 interrupt priority bit high. External interrupt 0 priority bit high. Figure 26. Interrupt Priority HIGH (IPH) Register 2003 Sep 11 40 SU01524 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM ......... C1 S5P2 C2 C3 C4 C5 .... S6 ......... .... .... ε Interrupt Goes Active Interrupts Are Polled Long Call to Interrupt Vector Address Interrupt Latched Interrupt Routine This is the fastest possible response when C2 is the final cycle of an instruction other than RETI or an access to IE or IP. SU00546 Figure 27. Interrupt Response Timing Diagram service routine is completed, or else another interrupt will be generated. The polling cycle/LCALL sequence is illustrated in Figure 27. Note that if an interrupt of higher priority level goes active prior to S5P2 of the machine cycle labeled C3 in Figure 27, then in accordance with the above rules it will be vectored to during C5 and C6, without any instruction of the lower priority routine having been executed. Response Time The INT0 and INT1 levels are inverted and latched into IE0 and IE1 at S5P2 of every machine cycle. The values are not actually polled by the circuitry until the next machine cycle. If a request is active and conditions are right for it to be acknowledged, a hardware subroutine call to the requested service routine will be the next instruction to be executed. The call itself takes two cycles. Thus, a minimum of three complete machine cycles elapse between activation of an external interrupt request and the beginning of execution of the first instruction of the service routine. Figure 27 shows interrupt response timings. Thus the processor acknowledges an interrupt request by executing a hardware-generated LCALL to the appropriate servicing routine. In some cases it also clears the flag that generated the interrupt, and in other cases it doesn’t. It never clears the Serial Port flag. This has to be done in the user’s software. It clears an external interrupt flag (IE0 or IE1) only if it was transition-activated. The hardware-generated LCALL pushes the contents of the Program Counter on to the stack (but it does not save the PSW) and reloads the PC with an address that depends on the source of the interrupt being vectored to, as shown in Table 10. A longer response time would result if the request is blocked by one of the 3 previously listed conditions. If an interrupt of equal or higher priority level is already in progress, the additional wait time obviously depends on the nature of the other interrupt’s service routine. If the instruction in progress is not in its final cycle, the additional wait time cannot be more the 3 cycles, since the longest instructions (MUL and DIV) are only 4 cycles long, and if the instruction in progress is RETI or an access to IE or IP, the additional wait time cannot be more than 5 cycles (a maximum of one more cycle to complete the instruction in progress, plus 4 cycles to complete the next instruction if the instruction is MUL or DIV). Execution proceeds from that location until the RETI instruction is encountered. The RETI instruction informs the processor that this interrupt routine is no longer in progress, then pops the top two bytes from the stack and reloads the Program Counter. Execution of the interrupted program continues from where it left off. Note that a simple RET instruction would also have returned execution to the interrupted program, but it would have left the interrupt control system thinking an interrupt was still in progress, making future interrupts impossible. Thus, in a single-interrupt system, the response time is always more than 3 cycles and less than 9 cycles. External Interrupts The external sources can be programmed to be level-activated or transition-activated by setting or clearing bit IT1 or IT0 in Register TCON. If ITx = 0, external interrupt x is triggered by a detected low at the INTx pin. If ITx = 1, external interrupt x is edge triggered. In this mode if successive samples of the INTx pin show a high in one cycle and a low in the next cycle, interrupt request flag IEx in TCON is set. Flag bit IEx then requests the interrupt. As previously mentioned, the derivatives described in this data sheet have a four-level interrupt structure. The corresponding registers are IE, IP and IPH. (See Figures 24, 25, and 26.) The IPH (Interrupt Priority High) register makes the four-level interrupt structure possible. The function of the IPH SFR is simple and when combined with the IP SFR determines the priority of each interrupt. The priority of each interrupt is determined as shown in the following table: Since the external interrupt pins are sampled once each machine cycle, an input high or low should hold for at least 12 oscillator periods to ensure sampling. If the external interrupt is transition-activated, the external source has to hold the request pin high for at least one cycle, and then hold it low for at least one cycle. This is done to ensure that the transition is seen so that interrupt request flag IEx will be set. IEx will be automatically cleared by the CPU when the service routine is called. PRIORITY BITS If the external interrupt is level-activated, the external source has to hold the request active until the requested interrupt is actually generated. Then it has to deactivate the request before the interrupt 2003 Sep 11 41 INTERRUPT PRIORITY LEVEL IPH.x IP.x 0 0 Level 0 (lowest priority) 0 1 Level 1 1 0 Level 2 1 1 Level 3 (highest priority) Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM interrupt is being serviced, it will be stopped and the new interrupt serviced. When the new interrupt is finished, the lower priority level interrupt that was stopped will be completed. An interrupt will be serviced as long as an interrupt of equal or higher priority is not already being serviced. If an interrupt of equal or higher level priority is being serviced, the new interrupt will wait until it is finished before being serviced. If a lower priority level Table 10. Interrupt Table SOURCE POLLING PRIORITY REQUEST BITS HARDWARE CLEAR? N (L)1 Y VECTOR ADDRESS (T)2 External interrupt 0 1 IE0 Timer 0 2 TF0 Y 03H External interrupt 1 3 IE1 N (L) Y (T) 13H Timer 1 4 TF1 Y 1BH UART 5 RI, TI N 23H Timer 2 6 TF2, EXF2 N 2BH 0BH NOTES: 1. L = Level activated 2. T = Transition activated Reduced EMI Mode The GF2 bit is a general purpose user-defined flag. The AO bit (AUXR.0) in the AUXR register when set disables the ALE output, unless the CPU needs to perform an off-chip memory access. Note that bit 2 is not writable and is always read as a zero. This allows the DPS bit to be quickly toggled simply by executing an INC AUXR1 instruction without affecting the GF2 bit. AUXR (8EH) 7 6 5 4 3 2 1 0 – – – – – – EXTRAM AO AUXR.0 AUXR.1 AO EXTRAM DPS Turns off ALE output. Controls external data memory access. BIT0 AUXR1 DPTR1 DPTR0 DPH (83H) DPL (82H) Dual DPTR SU00745A The dual DPTR structure (see Figure 28) enables a way to specify the address of an external data memory location. There are two 16-bit DPTR registers that address the external memory, and a single bit called DPS = AUXR1/bit0 that allows the program code to switch between them. Figure 28. DPTR Instructions The instructions that refer to DPTR refer to the data pointer that is currently selected using the AUXR1/bit 0 register. The six instructions that use the DPTR are as follows: • New Register Name: AUXR1# • SFR Address: A2H • Reset Value: xxx000x0B AUXR1 (A2H) 7 6 5 4 3 2 1 0 – – – – GF2 0 – DPS Where: DPS = AUXR1/bit0 = Switches between DPTR0 and DPTR1. Select Reg DPS DPTR0 0 DPTR1 1 INC DPTR Increments the data pointer by 1 MOV DPTR, #data16 Loads the DPTR with a 16-bit constant MOV A, @ A+DPTR Move code byte relative to DPTR to ACC MOVX A, @ DPTR Move external RAM (16-bit address) to ACC MOVX @ DPTR , A Move ACC to external RAM (16-bit address) JMP @ A + DPTR Jump indirect relative to DPTR The data pointer can be accessed on a byte-by-byte basis by specifying the low or high byte in an instruction which accesses the SFRs. See application note AN458 for more details. The DPS bit status should be saved by software when switching between DPTR0 and DPTR1. 2003 Sep 11 EXTERNAL DATA MEMORY 42 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM For example: Expanded Data RAM Addressing The P89C60X2 has internal data memory that is mapped into four separate segments: the lower 128 bytes of RAM, upper 128 bytes of RAM, 128 bytes Special Function Register (SFR), and 256 bytes expanded RAM (ERAM) (768 bytes for the P89C61X2). where R0 contains 0A0H, accesses the data byte at address 0A0H, rather than P2 (whose address is 0A0H). The four segments are: 1. The Lower 128 bytes of RAM (addresses 00H to 7FH) are directly and indirectly addressable. The ERAM can be accessed by indirect addressing, with EXTRAM bit cleared and MOVX instructions. This part of memory is physically located on-chip, logically occupies the first 256/768 bytes of external data memory in the P89C60X2/61X2. MOV @R0,acc 2. The Upper 128 bytes of RAM (addresses 80H to FFH) are indirectly addressable only. With EXTRAM = 0, the ERAM is indirectly addressed, using the MOVX instruction in combination with any of the registers R0, R1 of the selected bank or DPTR. An access to ERAM will not affect ports P0, P3.6 (WR#) and P3.7 (RD#). P2 SFR is output during external addressing. For example, with EXTRAM = 0, 3. The Special Function Registers, SFRs, (addresses 80H to FFH) are directly addressable only. 4. The 256/768-bytes expanded RAM (ERAM, 00H – 1FFH/2FFH) are indirectly accessed by move external instruction, MOVX, and with the EXTRAM bit cleared, see Figure 29. MOVX @R0,acc where R0 contains 0A0H, accesses the ERAM at address 0A0H rather than external memory. An access to external data memory locations higher than the ERAM will be performed with the MOVX DPTR instructions in the same way as in the standard 80C51, so with P0 and P2 as data/address bus, and P3.6 and P3.7 as write and read timing signals. Refer to Figure 30. The Lower 128 bytes can be accessed by either direct or indirect addressing. The Upper 128 bytes can be accessed by indirect addressing only. The Upper 128 bytes occupy the same address space as the SFR. That means they have the same address, but are physically separate from SFR space. With EXTRAM = 1, MOVX @Ri and MOVX @DPTR will be similar to the standard 80C51. MOVX @ Ri will provide an 8-bit address multiplexed with data on Port 0 and any output port pins can be used to output higher order address bits. This is to provide the external paging capability. MOVX @DPTR will generate a 16-bit address. Port 2 outputs the high-order eight address bits (the contents of DPH) while Port 0 multiplexes the low-order eight address bits (DPL) with data. MOVX @Ri and MOVX @DPTR will generate either read or write signals on P3.6 (WR) and P3.7 (RD). When an instruction accesses an internal location above address 7FH, the CPU knows whether the access is to the upper 128 bytes of data RAM or to SFR space by the addressing mode used in the instruction. Instructions that use direct addressing access SFR space. For example: MOV 0A0H,#data accesses the SFR at location 0A0H (which is P2). Instructions that use indirect addressing access the Upper 128 bytes of data RAM. The stack pointer (SP) may be located anywhere in the 256 bytes RAM (lower and upper RAM) internal data memory. The stack may not be located in the ERAM. AUXR Address = 8EH Reset Value = xxxx xx00B Not Bit Addressable — — — — — — EXTRAM AO 7 6 5 4 3 2 1 0 Bit: Symbol Function AO Disable/Enable ALE AO Operating Mode 0 ALE is emitted at a constant rate of 1/6 the oscillator frequency (12-clock mode; 1/3 fOSC in 6-clock mode). 1 ALE is active only during off-chip memory access. EXTRAM Internal/External RAM access using MOVX @Ri/@DPTR EXTRAM Operating Mode 0 Internal ERAM access using MOVX @Ri/@DPTR 1 External data memory access. — Not implemented, reserved for future use*. NOTE: *User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features. In that case, the reset or inactive value of the new bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate. SU01613 Figure 29. AUXR: Auxiliary Register 2003 Sep 11 43 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM FF FF UPPER 128 BYTES INTERNAL RAM ERAM 256 or 768 BYTES 80 FFFF SPECIAL FUNCTION REGISTER EXTERNAL DATA MEMORY 80 LOWER 128 BYTES INTERNAL RAM 100 00 00 0000 SU01293 Figure 30. Internal and External Data Memory Address Space with EXTRAM = 0 enabled, the user needs to service it by writing 01EH and 0E1H to WDTRST to avoid a WDT overflow. The 14-bit counter overflows when it reaches 16383 (3FFFH) and this will reset the device. When the WDT is enabled, it will increment every machine cycle while the oscillator is running. This means the user must reset the WDT at least every 16383 machine cycles. To reset the WDT, the user must write 01EH and 0E1h to WDTRST. WDTRST is a write only register. the WDT counter cannot be read or written. When the WDT overflows, it will generate an output RESET pulse at the reset pin (see note below). The RESET pulse duration is 98 TOSC (6-clock mode; 196 in 12-clock mode), where TOSC = 1/fOSC. To make the best use of the WDT, it should be serviced in those sections of code that will periodically be executed within the time required to prevent a WDT reset. HARDWARE WATCHDOG TIMER (ONE-TIME ENABLED WITH RESET-OUT FOR P89C51RA2/RB2/RC2/RD2xx) The WDT is intended as a recovery method in situations where the CPU may be subjected to software upset. The WDT consists of a 14-bit counter and the Watchdog Timer reset (WDTRST) SFR. The WDT is disabled at reset. To enable the WDT, the user must write 01EH and 0E1H in sequence to the WDTRST, SFR location 0A6H. When the WDT is enabled, it will increment every machine cycle while the oscillator is running and there is no way to disable the WDT except through reset (either hardware reset or WDT overflow reset). When the WDT overflows, it will drive an output reset HIGH pulse at the RST-pin (see the note below). Using the WDT To enable the WDT, the user must write 01EH and 0E1H in sequence to the WDTRST, SFR location 0A6H. When the WDT is 2003 Sep 11 44 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM ABSOLUTE MAXIMUM RATINGS1, 2, 3 PARAMETER Operating temperature under bias Storage temperature range Voltage on EA/VPP pin to VSS Voltage on any other pin to VSS Maximum IOL per I/O pin RATING UNIT 0 to +70 °C –65 to +150 °C 0 to +13.0 V –0.5 to +6.5 V 15 mA Power dissipation (based on package heat transfer limitations, not device power consumption) 1.5 W NOTES: 1. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any conditions other than those described in the AC and DC Electrical Characteristics section of this specification is not implied. 2. This product includes circuitry specifically designed for the protection of its internal devices from the damaging effects of excessive static charge. Nonetheless, it is suggested that conventional precautions be taken to avoid applying greater than the rated maximum. 3. Parameters are valid over operating temperature range unless otherwise specified. All voltages are with respect to VSS unless otherwise noted. AC ELECTRICAL CHARACTERISTICS Tamb = 0°C to +70°C CLOCK FREQUENCY RANGE SYMBOL 1/tCLCL 2003 Sep 11 FIGURE PARAMETER 35 Oscillator frequency OPERATING MODE POWER SUPPLY VOLTAGE MIN MAX UNIT 6-clock 5 V " 10% 0 20 MHz 12-clock 5 V " 10% 0 33 MHz 45 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM DC ELECTRICAL CHARACTERISTICS Tamb = 0 °C to +70 °C; VCC = 5 V ±10%; VSS = 0 V (20/33 MHz max. CPU clock) SYMBOL PARAMETER TEST CONDITIONS LIMITS MIN VIL Input low VIH voltage11 UNIT TYP1 MAX 4.5 V < VCC < 5.5 V –0.5 0.2 VCC–0.1 V Input high voltage (ports 0, 1, 2, 3, EA) – 0.2 VCC+0.9 VCC+0.5 V VIH1 Input high voltage, XTAL1, RST11 – 0.7 VCC VCC+0.5 V VOL Output low voltage, ports 1, 2, 3 8 VCC = 4.5 V; IOL = 1.6 mA2 – 0.4 V VOL1 Output low voltage, port 0, ALE, PSEN 7, 8 VCC = 4.5 V; IOL = 3.2 mA2 – 0.45 V VOH Output high voltage, ports 1, 2, 3 3 VCC = 4.5 V; IOH = –30 mA VCC – 0.7 – V VOH1 Output high voltage (port 0 in external bus mode), ALE9, PSEN3 VCC = 4.5 V; IOH = –3.2 mA VCC – 0.7 – V IIL Logical 0 input current, ports 1, 2, 3 VIN = 0.4 V –1 –75 mA ITL Logical 1-to-0 transition current, ports 1, 2, 36 VIN = 2.0 V; See note 4 – –650 mA ILI Input leakage current, port 0 0.45 < VIN < VCC – 0.3 – ±10 mA ICC Power supply current (see Figure 38): See note 5 100 mA Active mode (see Note 5) Idle mode (see Note 5) Power-down mode or clock stopped Tamb = 0 °C to 70 °C <30 (see Figure 42 for conditions) Programming and erase mode fOSC = 20MHz RRST Internal reset pull-down resistor – 40 60 225 mA kΩ CIO Pin capacitance10 (except EA) – – 15 pF NOTES: 1. Typical ratings are not guaranteed. The values listed are at room temperature, 5 V. 2. Capacitive loading on ports 0 and 2 may cause spurious noise to be superimposed on the VOLs of ALE and ports 1 and 3. The noise is due to external bus capacitance discharging into the port 0 and port 2 pins when these pins make 1-to-0 transitions during bus operations. In the worst cases (capacitive loading > 100 pF), the noise pulse on the ALE pin may exceed 0.8 V. In such cases, it may be desirable to qualify ALE with a Schmitt Trigger, or use an address latch with a Schmitt Trigger STROBE input. IOL can exceed these conditions provided that no single output sinks more than 5 mA and no more than two outputs exceed the test conditions. 3. Capacitive loading on ports 0 and 2 may cause the VOH on ALE and PSEN to momentarily fall below the VCC–0.7 specification when the address bits are stabilizing. 4. Pins of ports 1, 2 and 3 source a transition current when they are being externally driven from 1 to 0. The transition current reaches its maximum value when VIN is approximately 2 V. 5. See Figures 39 through 42 for ICC test conditions and Figure 38 for ICC vs. Frequency. 12-clock mode characteristics: Active mode: ICC (MAX) = (8.5 + 0.62 FREQ. [MHz])mA Idle mode: ICC (MAX) = (3.5 + 0.18 FREQ. [MHz])mA 6. This value applies to Tamb = 0°C to +70°C. 7. Load capacitance for port 0, ALE, and PSEN = 100 pF, load capacitance for all other outputs = 80 pF. 8. Under steady state (non-transient) conditions, IOL must be externally limited as follows: Maximum IOL per port pin: 15 mA 26 mA Maximum IOL per 8-bit port: Maximum total IOL for all outputs: 71 mA If IOL exceeds the test condition, VOL may exceed the related specification. Pins are not guaranteed to sink current greater than the listed test conditions. 9. ALE is tested to VOH1, except when ALE is off then VOH is the voltage specification. 10. Pin capacitance is characterized but not tested. Pin capacitance is less than 25 pF. Pin capacitance of ceramic package is less than 15 pF (except EA is 25 pF). 11. To improve noise rejection a nominal 100 ns glitch rejection circuitry has been added to the RST pin, and a nominal 15 ns glitch rejection circuitry has been added to the INT0 and INT1 pins. Previous devices provided only an inherent 5 ns of glitch rejection. 2003 Sep 11 46 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM AC ELECTRICAL CHARACTERISTICS (12-CLOCK MODE) Tamb = 0 °C to +70 °C; VCC = 5 V ± 10%, VSS = 0 V1, 2, 3 SYMBOL VARIABLE CLOCK4 33 MHz CLOCK4 MIN MAX MIN 0 33 FIGURE PARAMETER 1/tCLCL 35 Oscillator frequency tLHLL 31 ALE pulse width 2tCLCL–40 21 ns tAVLL 31 Address valid to ALE low tCLCL–25 5 ns tLLAX 31 Address hold after ALE low tCLCL–25 tLLIV 31 ALE low to valid instruction in tLLPL 31 ALE low to PSEN low tCLCL–25 tPLPH 31 PSEN pulse width 3tCLCL–45 tPLIV 31 PSEN low to valid instruction in tPXIX 31 Input instruction hold after PSEN tPXIZ 31 Input instruction float after PSEN tCLCL–25 5 ns tAVIV 31 Address to valid instruction in 5tCLCL–80 70 ns tPLAZ 31 PSEN low to address float 10 10 ns MAX MHz 5 4tCLCL–65 ns 55 5 ns ns 45 3tCLCL–60 0 UNIT ns 30 0 ns ns Data Memory tRLRH 32 RD pulse width 6tCLCL–100 82 tWLWH 33 WR pulse width 6tCLCL–100 82 tRLDV 32 RD low to valid data in tRHDX 32 Data hold after RD tRHDZ 32 Data float after RD 2tCLCL–28 32 ns tLLDV 32 ALE low to valid data in 8tCLCL–150 90 ns tAVDV 32 Address to valid data in 105 ns tLLWL 32, 33 ALE low to RD or WR low 3tCLCL–50 140 ns tAVWL 32, 33 Address valid to WR low or RD low 4tCLCL–75 45 ns tQVWX 33 Data valid to WR transition tCLCL–30 0 ns tWHQX 33 Data hold after WR tCLCL–25 5 ns tQVWH 33 Data valid to WR high 7tCLCL–130 80 tRLAZ 32 RD low to address float tWHLH 32, 33 RD or WR high to ALE high tCLCL–25 tCLCL+25 5tCLCL–90 0 ns ns 60 0 9tCLCL–165 3tCLCL+50 40 0 5 ns ns ns 0 ns 55 ns External Clock tCHCX 35 High time 17 tCLCL–tCLCX ns tCLCX 35 Low time 17 tCLCL–tCHCX ns tCLCH 35 Rise time 5 ns tCHCL 35 Fall time 5 ns Shift Register tXLXL 34 Serial port clock cycle time 12tCLCL 360 ns tQVXH 34 Output data setup to clock rising edge 10tCLCL–133 167 ns tXHQX 34 Output data hold after clock rising edge 2tCLCL–80 50 ns tXHDX 34 Input data hold after clock rising edge 0 0 ns tXHDV 34 Clock rising edge to input data valid 10tCLCL–133 167 ns NOTES: 1. Parameters are valid over operating temperature range unless otherwise specified. 2. Load capacitance for port 0, ALE, and PSEN = 100 pF, load capacitance for all other outputs = 80 pF. 3. Interfacing the microcontroller to devices with float times up to 45 ns is permitted. This limited bus contention will not cause damage to Port 0 drivers. 4. Parts are tested to 3.5 MHz, but guaranteed to operate down to 0 Hz. 2003 Sep 11 47 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM AC ELECTRICAL CHARACTERISTICS (6-CLOCK MODE) Tamb = 0 °C to +70 °C; VCC = 5 V ± 10%, VSS = 0 V1, 2, 3 SYMBOL VARIABLE CLOCK4 20 MHz CLOCK4 MIN MAX MIN 0 20 FIGURE PARAMETER 1/tCLCL 35 Oscillator frequency tLHLL 31 ALE pulse width tCLCL–40 10 ns tAVLL 31 Address valid to ALE low 0.5tCLCL–20 5 ns tLLAX 31 Address hold after ALE low 0.5tCLCL–20 5 tLLIV 31 ALE low to valid instruction in tLLPL 31 ALE low to PSEN low 0.5tCLCL–20 tPLPH 31 PSEN pulse width 1.5tCLCL–45 tPLIV 31 PSEN low to valid instruction in tPXIX 31 Input instruction hold after PSEN tPXIZ 31 Input instruction float after PSEN 0.5tCLCL–20 5 ns tAVIV 31 Address to valid instruction in 2.5tCLCL–80 45 ns tPLAZ 31 PSEN low to address float 10 10 ns MAX MHz 2tCLCL–65 ns 35 5 ns ns 30 1.5tCLCL–60 0 UNIT ns 15 0 ns ns Data Memory tRLRH 32 RD pulse width 3tCLCL–100 50 tWLWH 33 WR pulse width 3tCLCL–100 50 tRLDV 32 RD low to valid data in tRHDX 32 Data hold after RD tRHDZ 32 Data float after RD tCLCL–20 5 ns tLLDV 32 ALE low to valid data in 4tCLCL–150 50 ns tAVDV 32 Address to valid data in 60 ns tLLWL 32, 33 ALE low to RD or WR low 1.5tCLCL–50 125 ns tAVWL 32, 33 Address valid to WR low or RD low 2tCLCL–75 25 ns tQVWX 33 Data valid to WR transition 0.5tCLCL–25 0 ns tWHQX 33 Data hold after WR 0.5tCLCL–20 5 ns tQVWH 33 Data valid to WR high 3.5tCLCL–130 45 tRLAZ 32 RD low to address float tWHLH 32, 33 RD or WR high to ALE high 0.5tCLCL–20 0.5tCLCL+20 2.5tCLCL–90 0 ns ns 35 0 4.5tCLCL–165 1.5tCLCL+50 25 0 5 ns ns ns 0 ns 45 ns External Clock tCHCX 35 High time 20 tCLCL–tCLCX ns tCLCX 35 Low time 20 tCLCL–tCHCX ns tCLCH 35 Rise time 5 ns tCHCL 35 Fall time 5 ns Shift Register tXLXL 34 Serial port clock cycle time 6tCLCL 300 ns tQVXH 34 Output data setup to clock rising edge 5tCLCL–133 117 ns tXHQX 34 Output data hold after clock rising edge tCLCL–30 20 ns tXHDX 34 Input data hold after clock rising edge 0 0 ns tXHDV 34 Clock rising edge to input data valid 5tCLCL–133 117 ns NOTES: 1. Parameters are valid over operating temperature range unless otherwise specified. 2. Load capacitance for port 0, ALE, and PSEN = 100 pF, load capacitance for all other outputs = 80 pF. 3. Interfacing the microcontroller to devices with float times up to 45 ns is permitted. This limited bus contention will not cause damage to Port 0 drivers. 4. Parts are tested to 2 MHz, but are guaranteed to operate down to 0 Hz. 2003 Sep 11 48 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM EXPLANATION OF THE AC SYMBOLS P – PSEN Q – Output data R – RD signal t – Time V – Valid W – WR signal X – No longer a valid logic level Z – Float Examples: tAVLL = Time for address valid to ALE low. tLLPL =Time for ALE low to PSEN low. Each timing symbol has five characters. The first character is always ‘t’ (= time). The other characters, depending on their positions, indicate the name of a signal or the logical status of that signal. The designations are: A – Address C – Clock D – Input data H – Logic level high I – Instruction (program memory contents) L – Logic level low, or ALE tLHLL ALE tAVLL tLLPL tPLPH tLLIV tPLIV PSEN tLLAX INSTR IN A0–A7 PORT 0 tPXIZ tPLAZ tPXIX A0–A7 tAVIV PORT 2 A0–A15 A8–A15 SU00006 Figure 31. External Program Memory Read Cycle ALE tWHLH PSEN tLLDV tLLWL tRLRH RD tAVLL tLLAX tRLAZ PORT 0 tRHDZ tRLDV tRHDX A0–A7 FROM RI OR DPL DATA IN A0–A7 FROM PCL INSTR IN tAVWL tAVDV PORT 2 P2.0–P2.7 OR A8–A15 FROM DPF A0–A15 FROM PCH SU00025 Figure 32. External Data Memory Read Cycle 2003 Sep 11 49 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM ALE tWHLH PSEN tWLWH tLLWL WR tLLAX tAVLL tWHQX tQVWX tQVWH A0–A7 FROM RI OR DPL PORT 0 DATA OUT A0–A7 FROM PCL INSTR IN tAVWL PORT 2 P2.0–P2.7 OR A8–A15 FROM DPF A0–A15 FROM PCH SU00026 Figure 33. External Data Memory Write Cycle INSTRUCTION 0 1 2 3 4 5 6 7 8 ALE tXLXL CLOCK tXHQX tQVXH OUTPUT DATA 0 1 2 WRITE TO SBUF 3 4 5 6 7 tXHDX tXHDV SET TI INPUT DATA VALID VALID VALID VALID VALID VALID VALID VALID CLEAR RI SET RI SU00027 Figure 34. Shift Register Mode Timing VCC–0.5 0.45V 0.7VCC 0.2VCC–0.1 tCHCL tCHCX tCLCH tCLCX tCLCL SU00009 Figure 35. External Clock Drive 2003 Sep 11 50 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM VCC–0.5 VLOAD+0.1V 0.2VCC+0.9 TIMING REFERENCE POINTS VLOAD 0.2VCC–0.1 0.45V VLOAD–0.1V SU00717 SU00718 Figure 36. AC Testing Input/Output Figure 37. Float Waveform 60 50 P89C60X2/61X2 MAXIMUM ICC ACTIVE 40 30 TYPICAL ICC ACTIVE 20 MAXIMUM IDLE 10 TYPICAL IDLE 4 8 12 16 20 24 28 32 36 Frequency at XTAL1 (MHz, 12-clock mode) SU01675 Figure 38. ICC vs. FREQ for 12-clock operation Valid only within frequency specifications 2003 Sep 11 VOL+0.1V NOTE: For timing purposes, a port is no longer floating when a 100mV change from load voltage occurs, and begins to float when a 100mV change from the loaded VOH/VOL level occurs. IOH/IOL ≥ ±20mA. NOTE: AC inputs during testing are driven at VCC –0.5 for a logic ‘1’ and 0.45V for a logic ‘0’. Timing measurements are made at VIH min for a logic ‘1’ and VIL max for a logic ‘0’. ICC (mA) VOH–0.1V 51 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM VCC VCC ICC ICC VCC VCC VCC VCC RST RST P0 P0 EA EA (NC) XTAL2 (NC) XTAL2 CLOCK SIGNAL XTAL1 CLOCK SIGNAL XTAL1 VSS VSS SU00719 SU00720 Figure 39. ICC Test Condition, Active Mode All other pins are disconnected VCC–0.5 Figure 40. ICC Test Condition, Idle Mode All other pins are disconnected 0.7VCC 0.2VCC–0.1 0.45V tCHCL tCHCX tCLCH tCLCX tCLCL SU00009 Figure 41. Clock Signal Waveform for ICC Tests in Active and Idle Modes tCLCH = tCHCL = 5ns VCC ICC VCC VCC RST P0 EA (NC) XTAL2 XTAL1 VSS SU00016 Figure 42. ICC Test Condition, Power Down Mode All other pins are disconnected. VCC = 2 V to 5.5 V 2003 Sep 11 VCC 52 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM PLCC44: plastic leaded chip carrier; 44 leads 2003 Sep 11 SOT187-2 53 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM DIP40: plastic dual in-line package; 40 leads (600 mil) 2003 Sep 11 54 SOT129-1 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM LQFP44: plastic low profile quad flat package; 44 leads; body 10 x 10 x 1.4 mm 2003 Sep 11 55 SOT389-1 Philips Semiconductors Product data 80C51 8-bit Flash microcontroller family P89C60X2/61X2 64KB Flash, 512B/1024B RAM REVISION HISTORY Rev Date Description _2 20030911 Preliminary data (9397 750 11927); ECN 853-2400 30250 of 25 August 2003 Modifications: • Added Watchdog Timer feature • Added DIP40 package _1 20020723 Preliminary data (9397 750 10131) Data sheet status Level Data sheet status [1] Product status [2] [3] Definitions I Objective data Development This data sheet contains data from the objective specification for product development. Philips Semiconductors reserves the right to change the specification in any manner without notice. II Preliminary data Qualification This data sheet contains data from the preliminary specification. Supplementary data will be published at a later date. Philips Semiconductors reserves the right to change the specification without notice, in order to improve the design and supply the best possible product. III Product data Production This data sheet contains data from the product specification. Philips Semiconductors reserves the right to make changes at any time in order to improve the design, manufacturing and supply. Relevant changes will be communicated via a Customer Product/Process Change Notification (CPCN). [1] Please consult the most recently issued data sheet before initiating or completing a design. [2] The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at URL http://www.semiconductors.philips.com. [3] For data sheets describing multiple type numbers, the highest-level product status determines the data sheet status. Definitions Short-form specification — The data in a short-form specification is extracted from a full data sheet with the same type number and title. For detailed information see the relevant data sheet or data handbook. Limiting values definition — Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 60134). Stress above one or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability. Application information — Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Disclaimers Life support — These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. Philips Semiconductors customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application. Right to make changes — Philips Semiconductors reserves the right to make changes in the products—including circuits, standard cells, and/or software—described or contained herein in order to improve design and/or performance. When the product is in full production (status ‘Production’), relevant changes will be communicated via a Customer Product/Process Change Notification (CPCN). Philips Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright, or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless otherwise specified. Koninklijke Philips Electronics N.V. 2003 All rights reserved. Printed in U.S.A. Contact information For additional information please visit http://www.semiconductors.philips.com. Fax: +31 40 27 24825 Date of release: 09-03 For sales offices addresses send e-mail to: [email protected]. Document order number: 2003 Sep 11 56 9397 750 11927