September 1996 COP87L88EK/COP87L84EK 8-Bit One Time Programmable (OTP) Microcontroller with Analog Function Block General Description Y The COP87L88EK/COP87L84EK OTP microcontrollers are members of the COP8TM feature family using an 8-bit core architecture. It is pin and software compatible to the mask ROM COP888EK/COP884EK product family. (Continued) Key Features Y Y Y Y Y CPU/Instruction Set Features Y Analog function block with Ð Analog comparator with seven input multiplexor Ð Constant current source and VCC/2 reference Three 16-bit timers, each with two 16-bit registers supporting: Ð Processor independent PWM mode Ð External event counter mode Ð Input capture mode 8 kbytes on-board EPROM with security feature 256 bytes on-board RAM Y Y Y Y Additional Peripheral Features Y Y Y Y Idle timer Multi-Input Wake-Up (MIWU) with optional interrupts (8) WATCHDOGTM and clock monitor logic MICROWIRE/PLUSTM serial I/O Y Y Memory mapped I/O Software selectable I/O options (TRI-STATEÉ output, push-pull output, weak pull-up input, high impedance input) 1 ms instruction cycle time Twelve multi-source vectored interrupts servicing Ð External interrupt Ð Idle timer T0 Ð Three timers (Each with 2 interrupts) Ð MICROWIRE/PLUS Ð Multi-Input Wake Up Ð Software trap Ð Default VIS (default interrupt) Versatile and easy to use instruction set 8-bit Stack Pointer (SP)Ðstack in RAM Two 8-bit register indirect data memory pointers (B and X) Fully Static CMOS Y Y Y Features Schmitt trigger inputs on ports G and L Packages: Ð 44 PLCC with 40 I/O pins Ð 40 DIP with 36 I/O pins Ð 28 DIP/SO, each with 24 I/O pins Two power saving modes: HALT and IDLE Single supply operation: 2.7V to 5.5V Temperature ranges: b40§ to a 85§ C Development Support Y Y Emulation device for the COP888EK/COP884EK Real time emulation and full program debug offered by MetaLink Development System Block Diagram TL/DD/12520 – 1 FIGURE 1. Block Diagram TRI-STATEÉ is a registered trademark of National Semiconductor Corporation. MICROWIRE/PLUSTM , COP8TM microcontrollers, MICROWIRETM and WATCHDOGTM are trademarks of National Semiconductor Corporation. iceMASTERTM is a trademark of MetaLink Corporation. C1996 National Semiconductor Corporation TL/DD12520 RRD-B30M106/Printed in U. S. A. http://www.national.com COP87L88EK/COP87L84EK 8-Bit One Time Programmable (OTP) Microcontroller with Analog Function Block PRELIMINARY General Description (Continued) saving modes (HALT and IDLE), both with a multi-sourced wakeup/interrupt capability. This multi-sourced interrupt capability may also be used independent of the HALT or IDLE modes. Each I/O pin has software selectable configurations. The devices operate over a voltage range of 2.7V to 5.5V. High throughput is achieved with an efficient, regular instruction set operating at a maximum rate of 1 ms per instruction. It is a fully static part, fabricated using double-metal silicon gate microCMOS technology. The device is available as One-Time Programmable (OTP). Features include an 8-bit memory mapped architecture, MICROWIRE/PLUS serial I/O, three 16-bit timer/counters supporting three modes (Processor Independent PWM generation, External Event counter, and Input Capture mode capabilities), one analog comparator with seven input multiplexor, and two power Connection Diagrams Dual-In-Line Package Plastic Chip Carrier TL/DD/12520–2 Top View Order Number COP87L88EKV-XE See NS Plastic Chip Package Number V44A TL/DD/12520 – 3 Top View Order Number COP87L84EKN-XE See NS Molded Package Number N40A Dual-In-Line Package Note: -X Crystal Oscillator -E Halt Enable TL/DD/12520 – 4 Top View Order Number COP87L84EKN-XE See NS Molded Package Number N28B Order Number COP87L84EKM-XE See NS Molded Package Number M28B FIGURE 2. Connection Diagrams http://www.national.com 2 Connection Diagrams (Continued) Pinouts for 28-, 40- and 44-Pin Packages Port Type Alt. Fun Alt. Fun 28-Pin Pack. 40-Pin Pack. 44-Pin Pack. 11 12 13 14 15 16 17 18 17 18 19 20 21 22 23 24 17 18 19 20 25 26 27 28 25 26 27 28 1 2 3 4 35 36 37 38 3 4 5 6 39 40 41 42 3 4 5 6 19 20 21 22 25 26 27 28 29 30 31 32 7 8 9 10 9 10 9 10 11 12 11 12 13 14 15 16 13 14 15 16 L0 L1 L2 L3 L4 L5 L6 L7 I/O I/O I/O I/O I/O I/O I/O I/O MIWU MIWU MIWU MIWU MIWU MIWU MIWU MIWU G0 G1 G2 G3 G4 G5 G6 G7 I/O WDOUT I/O I/O I/O I/O I I/CKO INT D0 D1 D2 D3 O O O O I0 I1 I I I2 I3 I I COMPIN1 a COMPINb/Current Source Out COMPIN0 a COMPOUT/COMPIN2 a I4 I5 I6 I7 I I I I COMPIN3 a COMPIN4 a COMPIN5 a COMPOUT D4 D5 D6 D7 O O O O 29 30 31 32 33 34 35 36 C0 C1 C2 C3 C4 C5 C6 C7 I/O I/O I/O I/O I/O I/O I/O I/O 39 40 1 2 43 44 1 2 21 22 23 24 8 33 7 34 8 37 7 38 T2A T2B T3A T3B T1B T1A SO SK SI HALT Restart VCC GND CKI RESET 6 23 5 24 3 http://www.national.com Absolute Maximum Ratings Total Current out of GND Pin (Sink) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributors for availability and specifications. Supply Voltage (VCC) Voltage at Any Pin Total Current into VCC Pin (Source) Storage Temperature Range Note: Absolute maximum ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications are not ensured when operating the device at absolute maximum ratings. 7V b 0.3V to VCC a 0.3V 100 mA DC Electrical Characteristics Parameter b 40§ C s TA s a 85§ C unless otherwise specified Conditions Max Units 5.5 0.1 VCC V V 16.5 6.5 mA mA VCC e 5.5V, CKI e 0 MHz VCC e 4.0V, CKI e 0 MHz 12 8 mA mA VCC e 5.5V, tc e 1 ms VCC e 4.0V, tc e 10 ms 3.5 0.7 mA mA 0.2 VCC V V 0.2 VCC V V Operating Voltage Power Supply Ripple (Note 1) Peak-to-Peak Supply Current (Note 2) CKI e 10 MHz CKI e 4 MHz VCC e 5.5V, tc e 1 ms VCC e 4.0V, tc e 2.5 ms HALT Current (Note 3) IDLE Current (Note 2) CKI e 10 MHz CKI e 1 MHz Min 2.7 Input Levels (VIH, VIL) RESET Logic High Logic Low CKI, All Other Inputs Logic High Logic Low 0.7 VCC VCC e 5.5V Input Pullup Current VCC e 5.5V, VIN e 0V b2 a2 mA b 40 b 250 mA 0.35 VCC V G and L Port Input Hysteresis (Note 7) TRI-STATE Leakage VCC e 4.5V, VOH e 3.3V VCC e 4.5V, VOL e 1V b 0.4 VCC e 4.5V, VOH e 2.7V VCC e 4.5V, VOH e 3.3V VCC e 4.5V, VOL e 0.4V b 10 b 0.4 VCC e 5.5V Room Temp RAM Retention Voltage, Vr 500 ns Rise and Fall Time (Min) Input Capacitance (Note 6) Load Capacitance on D2 (Note 6) 4 b 110 mA mA mA a2 mA 15 3 mA mA g 200 mA 7 pF 1000 pF 1.6 b2 Maximum Input Current without Latchup (Note 5) mA mA 10 Allowable Sink/Source Current per Pin (Note 7) D Outputs (Sink) All others http://www.national.com Typ 0.8 VCC Hi-Z Input Leakage Output Current Levels D Outputs Source Sink (Note 4) All Others Source (Weak Pull-Up Mode) Source (Push-Pull Mode) Sink (Push-Pull Mode) 110 mA b 65§ C to a 140§ C 2 V AC Electrical Characteristics b40§ C s TA s a 85§ C unless otherwise specified Parameter Conditions Min Instruction Cycle Time (tc) Crystal, Resonator, R/C Oscillator 4.5V s VCC s 5.5V 4.5V s VCC s 5.5V 1.0 3.0 Inputs tSETUP tHOLD 4.5V s VCC s 5.5V 4.5V s VCC s 5.5V 200 60 Output Propagation Delay (Note 6) tPD1, tPD0 SO, SK All Others 4.5V s VCC s 5.5V 4.5V s VCC s 5.5V MICROWIRETM Setup Time (tUWS) (Note 7) MICROWIRE Hold Time (tUWH) (Note 7) MICROWIRE Output Propagation Delay (tUPD) VCC t 4.5V VCC t 4.5V VCC t 4.5V Typ Max Units DC DC ms ms ns ns RL e 2.2k, CL e 100 pF 0.7 1 ms ms 220 ns ns ns 20 56 Input Pulse Width (Note 7) Interrupt Input High Time Interrupt Input Low Time Timer 1, 2, 3 Input High Time Timer 1, 2, 3 Input Low Time 1.0 1.0 1.0 1.0 tc tc tc tc Reset Pulse Width 1.0 ms tc e Instruction Cycle Time Note 1: Maximum rate of voltage change must be k 0.5 V/ms. Note 2: Supply and IDLE currents are measured with CKI driven with a square wave Oscillator, CKO driven 180§ out of phase with CKI, inputs connected to VCC and outputs driven low but not connected to a load. Note 3: The HALT mode will stop CKI from oscillating in the RC and the Crystal configurations by bringing CKI high. Measurement of IDD HALT is done with device neither sourcing nor sinking current; with L, C, and G0–G5 programmed as low outputs and not driving a load; all outputs programmed low and not driving a load; all inputs tied to VCC; clock monitor and comparator disabled. Parameter refers to HALT mode entered via setting bit 7 of the G Port data register. Part will pull up CKI during HALT in crystal clock mode. Note 4: The user must guarantee that D2 pin does not source more than 10 mA during RESET. If D2 sources more than 10 mA during reset, the device will go into programming mode. Note 5: Pins G6 and RESET are designed with a high voltage input network. These pins allow input voltages l VCC and the pins will have sink current to VCC when biased at voltages l VCC (the pins do not have source current when biased at a voltage below VCC). The effective resistance to VCC is 750X (typical). These two pins will not latch up. The voltage at the pins must be limited to k 14V. WARNING: Voltages in excess of 14V will cause damage to the pins. This warning excludes ESD transients. Note 6: The output propagation delay is referenced to the end of the instruction cycle where the output change occurs. Note 7: Parameter characterized but not tested. 5 http://www.national.com Analog Function Block VCC e 5.0V, b40§ C s TA s a 85§ C Parameter Input Offset Voltage Conditions Min 0.4V k VIN k VCC b 1.5V Input Common Mode Voltage Range (Note 8) Max Units g 25 mV 0.4 VCC/2 Reference 4.5V k VCC k 5.5V DC Supply Current for Comparator (when enabled) VCC e 5.5V DC Supply Current for VCC/2 Reference (when enabled) VCC e 5.5V DC Supply Current for Constant Current Source (when enabled) VCC e 5.5V Constant Current Source 4.5V k VCC k 5.5V Current Source Variation over Common Mode Range 4.5V k VCC k 5.5V 0.5 VCC b 0.04 0.5 VCC 50 10 20 Temp e Constant Current Source Enable Time Comparator Response Time Typ g 10 1.5 100 mV Overdrive, 100 pF Load VCC b 1.5 V 0.5 VCC a 0.04 V 250 mA 80 mA 200 mA 40 mA g2 mA 2 ms 1 ms Note 8: The device is capable of operating over a common mode voltage range of 0 to VCC b 1.5V, however increased offset voltage will be observed between 0V and 0.4V. TL/DD/12520 – 5 FIGURE 3. MICROWIRE/PLUS Timing http://www.national.com 6 Pin Descriptions VCC and GND are the power supply pins. All VCC and GND pins must be connected. T2B. L6 and L7 are used for the timer input functions T3A and T3B. CKI is the clock input. This can come from an R/C generated oscillator, or a crystal oscillator (in conjunction with CKO). See Oscillator Description section. RESET is the master reset input. See Reset Description section. The device contains three bidirectional 8-bit I/O ports (C, G and L), where each individual bit may be independently configured as an input (Schmitt Trigger inputs on ports L and G), output or TRI-STATE under program control. Three data memory address locations are allocated for each of these I/O ports. Each I/O port has two associated 8-bit memory mapped registers, the CONFIGURATION register and the output DATA register. A memory mapped address is also reserved for the input pins of each I/O port. (See the memory map for the various addresses associated with the I/O ports.) Figure 4 shows the I/O port configurations. The DATA and CONFIGURATION registers allow for each port bit to be individually configured under software control as shown below: The Port L has the following alternate features: L0 MIWU L1 MIWU L2 MIWU L3 MIWU L4 MIWU or T2A L5 MIWU or T2B L6 MIWU or T3A L7 MIWU or T3B Port G is an 8-bit port with 5 I/O pins (G0, G2 – G5), an input pin (G6), and a dedicated output pin (G7). Pins G0 and G2 – G6 all have Schmitt Triggers on their inputs. Pin G1 serves as the dedicated WDOUT WATCHDOG output, while pin G7 is either input or output depending on the oscillator mask option selected. With the crystal oscillator option selected, G7 serves as the dedicated output pin for the CKO clock output. With the single-pin R/C oscillator mask option selected, G7 serves as a general purpose input pin but is also used to bring the device out of HALT mode with a low to high transition on G7. There are two registers associated with the G Port, a data register and a configuration register. Therefore, each of the 5 I/O bits (G0, G2 – G5) can be individually configured under software control. Since G6 is an input only pin and G7 is the dedicated CKO clock output pin (crystal clock option) or general purpose input (R/C clock option), the associated bits in the data and configuration registers for G6 and G7 are used for special purpose functions as outlined on the next page. Reading the G6 and G7 data bits will return zeros. CONFIGURATION Register DATA Register 0 0 0 1 1 1 0 1 Port Set-Up Hi-Z Input (TRI-STATE Output) Input with Weak Pull-Up Push-Pull Zero Output Push-Pull One Output PORT L is an 8-bit I/O port. All L-pins have Schmitt triggers on the inputs. The Port L supports Multi-Input Wake Up on all eight pins. L4 and L5 are used for the timer input functions T2A and TL/DD/12520 – 6 FIGURE 4. I/O Port Configurations 7 http://www.national.com CPU REGISTERS The CPU can do an 8-bit addition, subtraction, logical or shift operation in one instruction (tc) cycle time. Pin Descriptions (Continued) Note that the chip will be placed in the HALT mode by writing a ‘‘1’’ to bit 7 of the Port G Data Register. Similarly the chip will be placed in the IDLE mode by writing a ‘‘1’’ to bit 6 of the Port G Data Register. Writing a ‘‘1’’ to bit 6 of the Port G Configuration Register enables the MICROWIRE/PLUS to operate with the alternate phase of the SK clock. The G7 configuration bit, if set high, enables the clock start up delay after HALT when the R/C clock configuration is used. Config Reg. Data Reg. G7 CLKDLY HALT G6 Alternate SK IDLE There are six CPU registers: A is the 8-bit Accumulator Register PC is the 15-bit Program Counter Register PU is the upper 7 bits of the program counter (PC) PL is the lower 8 bits of the program counter (PC) B is an 8-bit RAM address pointer, which can be optionally post auto incremented or decremented. X is an 8-bit alternate RAM address pointer, which can be optionally post auto incremented or decremented. SP is the 8-bit stack pointer, which points to the subroutine/ interrupt stack (in RAM). The SP is initialized to RAM address 06F with reset. S is the 8-bit Data Segment Address Register used to extend the lower half of the address range (00 to 7F) into 256 data segments of 128 bytes each. All the CPU registers are memory mapped with the exception of the Accumulator (A) and the Program Counter (PC). Port G has the following alternate features: G0 INTR (External Interrupt Input) G2 T1B (Timer T1 Capture Input) G3 T1A (Timer T1 I/O) G4 SO (MICROWIRE Serial Data Output) G5 SK (MICROWIRE Serial Clock) PROGRAM MEMORY The program memory consists of 8 kbytes of OTP EPROM. These bytes may hold program instructions or constant data (data tables for the LAID instruction, jump vectors for the JID instruction, and interrupt vectors for the VIS instruction). The program memory is addressed by the 15-bit program counter (PC). All interrupts in the devices vector to program memory location 0FF Hex. The device can be configured to inhibit external reads of the program memory. This is done by programming the Security Byte. G6 SI (MICROWIRE Serial Data Input) Port G has the following dedicated functions: G1 WDOUT WATCHDOG and/or Clock Monitor dedicated output G7 CKO Oscillator dedicated output or general purpose input Port C is an 8-bit I/O port. The 40-pin device does not have a full complement of Port C pins. The unavailable pins are not terminated. A read operation for these unterminated pins will return unpredicatable values. Port I is an eight-bit Hi-Z input port. Port I0 – I7 are used for the analog function block. The Port I has the following alternate features: I0 COMPIN1 a (Comparator Positive Input 1) I1 I2 I3 I4 SECURITY FEATURE The program memory array has an associate Security Byte that is located outside of the program address range. This byte can be addressed only from programming mode by a programmer tool. Security is an optional feature and can only be asserted after the memory array has been programmed and verified. A secured part will read all 00(hex) by a programmer. The part will fail Blank Check and will fail Verify operations. A Read operation will fill the programmer’s memory with 00(hex). The Security Byte itself is always readable with value of 00(hex) if unsecure and FF(hex) if secure. COMPINb (Comparator Negative Input/Current Source Out) COMPIN0 a (Comparator Positive Input 0) COMPOUT/COMPIN2 a (Comparator Output/ Comparator Positive Input 2)) COMPIN3 a (Comparator Positive Input 3) I5 COMPIN4 a (Comparator Positive Input 4) I6 COMPIN5 a (Comparator Positive Input 5) I7 COMPOUT (Comparator Output) Port D is an 8-bit output port that is preset high when RESET goes low. The user can tie two or more D port outputs (except D2) together in order to get a higher drive. DATA MEMORY The data memory address space includes the on-chip RAM and data registers, the I/O registers (Configuration, Data and Pin), the control registers, the MICROWIRE/PLUS SIO shift register, and the various registers, and counters associated with the timers (with the exception of the IDLE timer). Data memory is addressed directly by the instruction or indirectly by the B, X, SP pointers and S register. The data memory consists of 256 bytes of RAM. Sixteen bytes of RAM are mapped as ‘‘registers’’ at addresses 0F0 to 0FF Hex. These registers can be loaded immediately, and also decremented and tested with the DRSZ (decrement register and skip if zero) instruction. The memory pointer registers X, SP, B and S are memory mapped into this space at address locations 0FC to 0FF Hex respectively, with the other registers being available for general usage. Note: Care must be exercised with the D2 pin operation. At RESET, the external loads on this pin must ensure that the output voltages stay above 0.8 VCC to prevent the chip from entering special modes. Also keep the external loading on D2 to k 1000 pF. Functional Description The architecture of the device is modified Harvard architecture. With the Harvard architecture, the control store program memory (ROM) is separated from the data store memory (RAM). Both ROM and RAM have their own separate addressing space with separate address buses. The architecture, though based on Harvard architecture, permits transfer of data from ROM to RAM. http://www.national.com 8 dresses 00F0 to 00FF of the upper base segment. No RAM is located at the upper sixteen addresses (0070 to 007F) of the lower base segment. Functional Description (Continued) The instruction set permits any bit in memory to be set, reset or tested. All I/O and registers (except A and PC) are memory mapped; therefore, I/O bits and register bits can be directly and individually set, reset and tested. The accumulator (A) bits can also be directly and individually tested. Note: RAM contents are undefined upon power-up. Data Memory Segment RAM Extension Data memory address 0FF is used as a memory mapped location for the Data Segment Address Register (S). The data store memory is either addressed directly by a single byte address within the instruction, or indirectly relative to the reference of the B, X, or SP pointers (each contains a single-byte address). This single-byte address allows an addressing range of 256 locations from 00 to FF hex. The upper bit of this single-byte address divides the data store memory into two separate sections as outlined previously. With the exception of the RAM register memory from address locations 00F0 to 00FF, all RAM memory is memory mapped with the upper bit of the single-byte address being equal to zero. This allows the upper bit of the single-byte address to determine whether or not the base address range (from 0000 to 00FF) is extended. If this upper bit equals one (representing address range 0080 to 00FF), then address extension does not take place. Alternatively, if this upper bit equals zero, then the data segment extension register S is used to extend the base address range (from 0000 to 007F) from XX00 to XX7F, where XX represents the 8 bits from the S register. Thus the 128-byte data segment extensions are located from addresses 0100 to 017F for data segment 1, 0200 to 027F for data segment 2, etc., up to FF00 to FF7F for data segment 255. The base address range from 0000 to 007F represents data segment 0. TL/DD/12520 – 7 *Reads as all ones. FIGURE 5. RAM Organization Additional RAM beyond these initial 128 bytes, however, will always be memory mapped in groups of 128 bytes (or less) at the data segment address extensions (XX00 to XX7F) of the lower base segment. The additional 128 bytes of RAM are memory mapped at address locations 0100 to 017F hex. Reset The RESET input when pulled low initializes the microcontroller. Initialization will occur whenever the RESET input is pulled low. Upon initialization, the data and configuration registers for ports L, G and C are cleared, resulting in these Ports being initialized to the TRI-STATE mode. Pin G1 of the G Port is an exception (as noted below) since pin G1 is dedicated as the WATCHDOG and/or Clock Monitor error output pin. Port D is set high. The PC, PSW, ICNTRL, CNTRL, T2CNTRL and T3CNTRL control registers are cleared. The Comparator Select Register is cleared. The S register is initialized to zero. The Multi-Input Wakeup registers WKEN and WKEDG are cleared. Wakeup register WKPND is unknown. The stack pointer, SP, is initialized to 6F hex. The device comes out of reset with both the WATCHDOG logic and the Clock Monitor detector armed, with the WATCHDOG service window bits set and the Clock Monitor bit set. The WATCHDOG and Clock Monitor circuits are inhibited during reset. The WATCHDOG service window bits being initialized high default to the maximum WATCHDOG service window of 64k tC clock cycles. The Clock Monitor bit being initialized high will cause a Clock Monitor error following reset if the clock has not reached the minimum specified frequency at the termination of reset. A Clock Monitor error will cause an active low error output on pin G1. This error output will continue until 16 tC –32 tC clock cycles following the clock frequency reaching the minimum specified value, at which time the G1 output will enter the TRI-STATE mode. The external RC network shown in Figure 6 should be used to ensure that the RESET pin is held low until the power supply to the chip stabilizes. Figure 5 illustrates how the S register data memory extension is used in extending the lower half of the base address range (00 to 7F hex) into 256 data segments of 128 bytes each, with a total addressing range of 32 kbytes from XX00 to XX7F. This organization allows a total of 256 data segments of 128 bytes each with an additional upper base segment of 128 bytes. Furthermore, all addressing modes are available for all data segments. The S register must be changed under program control to move from one data segment (128 bytes) to another. However, the upper base segment (containing the 16 memory registers, I/O registers, control registers, etc.) is always available regardless of the contents of the S register, since the upper base segment (address range 0080 to 00FF) is independent of data segment extension. The instructions that utilize the stack pointer (SP) always reference the stack as part of the base segment (Segment 0), regardless of the contents of the S register. The S register is not changed by these instructions. Consequently, the stack (used with subroutine linkage and interrupts) is always located in the base segment. The stack pointer will be intitialized to point at data memory location 006F as a result of reset. The 128 bytes of RAM contained in the base segment are split between the lower and upper base segments. The first 112 bytes of RAM are resident from address 0000 to 006F in the lower base segment, while the remaining 16 bytes of RAM represent the 16 data memory registers located at ad- 9 http://www.national.com TABLE A. Crystal Oscillator Configuration, TA e 25§ C Reset (Continued) R1 (kX) R2 (MX) C1 (pF) C2 (pF) CKI Freq (MHz) Conditions 0 0 0 1 1 1 30 30 200 30 – 36 30 – 36 100 – 150 10 4 0.455 VCC e 5V VCC e 5V VCC e 5V TABLE B. RC Oscillator Configuration, TA e 25§ C TL/DD/12520–8 RC l 5 c Power Supply Rise Time FIGURE 6. Recommended Reset Circuit Oscillator Circuits The chip can be driven by a clock input on the CKI input pin which can be between DC and 10 MHz. The CKO output clock is on pin G7 (crystal configuration). The CKI input frequency is divided down by 10 to produce the instruction cycle clock (1/tc). Figure 7 shows the Crystal and R/C oscillator diagrams. R (kX) C (pF) CKI Freq (MHz) Instr. Cycle (ms) Conditions 3.3 5.6 6.8 82 100 100 2.2 to 2.7 1.1 to 1.3 0.9 to 1.1 3.7 to 4.6 7.4 to 9.0 8.8 to 10.8 VCC e 5V VCC e 5V VCC e 5V Note: 3k s R s 200k 50 pF s C s 200 pF Control Registers CNTRL Register (Address XÊ 00EE) The Timer1 (T1) and MICROWIRE/PLUS control register contains the following bits: SL1 & SL0 Select the MICROWIRE/PLUS clock divide by (00 e 2, 01 e 4, 1x e 8) IEDG External interrupt edge polarity select (0 e Rising edge, 1 e Falling edge) MSEL Selects G5 and G4 as MICROWIRE/PLUS signals SK and SO respectively T1C0 Timer T1 Start/Stop control in timer modes 1 and 2 Timer T1 Underflow Interrupt Pending Flag in timer mode 3 T1C1 Timer T1 mode control bit T1C2 Timer T1 mode control bit T1C3 Timer T1 mode control bit CRYSTAL OSCILLATOR CKI and CKO can be connected to make a closed loop crystal (or resonator) controlled oscillator. Table A shows the component values required for various standard crystal values. R/C OSCILLATOR By selecting CKI as a single pin oscillator input, a single pin R/C oscillator circuit can be connected to it. CKO is available as a general purpose input, and/or HALT restart input. Note: Use of the R/C oscillator option will result in higher electromagnetic emissions. Table B shows the variation in the oscillator frequencies as functions of the component (R and C) values. T1C3 T1C2 T1C1 T1C0 MSEL IEDG Bit 7 TL/DD/12520–10 TL/DD/12520–9 FIGURE 7. Crystal and R/C Oscillator Diagrams http://www.national.com 10 SL1 SL0 Bit 0 Control Registers (Continued) PSW Register (Address XÊ 00EF) The PSW register contains the following select bits: GIE EXEN BUSY EXPND T1ENA Global interrupt enable (enables interrupts) Enable external interrupt MICROWIRE/PLUS busy shifting flag External interrupt pending Timer T1 Interrupt Enable for Timer Underflow or T1A Input capture edge T1PNDA Timer T1 Interrupt Pending Flag (Autoreload RA in mode 1, T1 Underflow in Mode 2, T1A capture edge in mode 3) C Carry Flag HC Half Carry Flag HC Timer T2 mode control bit T2C2 Timer T2 mode control bit T2C3 Timer T2 mode control bit T2C3 T2C2 T2C1 T2C0 T2PNDA T2ENA T2PNDB T2ENB Bit 7 Bit 0 T3CNTRL Register (Address XÊ 00B6) The T3CNTRL register contains the following bits: T3ENB Timer T3 Interrupt Enable for T3B T3PNDB Timer T3 Interrupt Pending Flag for T3B pin (T3B capture edge) T3ENA Timer T3 Interrupt Enable for Timer Underflow or T3A pin T3PNDA Timer T3 Interrupt Pending Flag (Autoload RA in mode 1, T3 Underflow in mode 2, T3a capture edge in mode 3) T3C0 Timer T3 Start/Stop control in timer modes 1 and 2 C T1PNDA T1ENA EXPND BUSY EXEN GIE Bit 7 Bit 0 The Half-Carry bit is also affected by all the instructions that affect the Carry flag. The SC (Set Carry) and RC (Reset Carry) instructions will respectively set or clear both the carry flags. In addition to the SC and RC instructions, ADC, SUBC, RRC and RLC instructions affect the carry and Half Carry flags. T3C1 T3C2 T3C3 ICNTRL Register (Address XÊ 00E8) The ICNTRL register contains the following bits: T1ENB Timer T1 Interrupt Enable for T1B Input capture edge T1PNDB Timer T1 Interrupt Pending Flag for T1B capture edge mWEN Enable MICROWIRE/PLUS interrupt mWPND MICROWIRE/PLUS interrupt pending T0EN Timer T0 Interrupt Enable (Bit 12 toggle) T0PND Timer T0 Interrupt pending LPEN L Port Interrupt Enable (Multi-Input Wakeup/Interrupt) Bit 7 could be used as a flag T3C3 T3C2 Bit 7 Timer T3 Underflow Interrupt Pending Flag in timer mode 3 Timer T3 mode control bit Timer T3 mode control bit Timer T3 mode control bit T3C1 T3C0 T3PNDA T3ENA T3PNDB T3ENB Bit 0 Timers The device contains a very versatile set of timers (T0, T1, T2, T3). All timers and associated autoreload/capture registers power up containing random data. TIMER T0 (IDLE TIMER) The device supports applications that require maintaining real time and low power with the IDLE mode. This IDLE mode support is furnished by the IDLE timer T0, which is a 16-bit timer. The Timer T0 runs continuously at the fixed rate of the instruction cycle clock, tc. The user cannot read or write to the IDLE Timer T0, which is a count down timer. The Timer T0 supports the following functions: Unused LPEN T0PND T0EN mWPND mWEN T1PNDB T1ENB Bit 7 T2C1 Bit 0 T2CNTRL Register (Address XÊ 00C6) The T2CNTRL register contains the following bits: T2ENB Timer T2 Interrupt Enable for T2B Input capture edge T2PNDB Timer T2 Interrupt Pending Flag for T2B capture edge T2ENA Timer T2 Interrupt Enable for Timer Underflow or T2A Input capture edge T2PNDA Timer T2 Interrupt Pending Flag (Autoreload RA in mode 1, T2 Underflow in mode 2, T2A capture edge in mode 3) T2C0 Timer T2 Start/Stop control in timer modes 1 and 2 Timer T2 Underflow Interrupt Pending Flag in timer mode 3 X Exit out of the Idle Mode (See Idle Mode description) X WATCHDOG logic (See WATCHDOG description) Start up delay out of the HALT mode The IDLE Timer T0 can generate an interrupt when the thirteenth bit toggles. This toggle is latched into the T0PND pending flag, and will occur every 4 ms at the maximum clock frequency (tc e 1 ms). A control flag T0EN allows the interrupt from the thirteenth bit of Timer T0 to be enabled or disabled. Setting T0EN will enable the interrupt, while resetting it will disable the interrupt. X 11 http://www.national.com Timers (Continued) TIMER T1, TIMER T2 AND TIMER T3 The device has a set of three powerful timer/counter blocks, T1, T2 and T3. The associated features and functioning of a timer block are described by referring to the timer block Tx. Since the three timer blocks, T1, T2 and T3 are identical, all comments are equally applicable to any of the three timer blocks. Each timer block consists of a 16-bit timer, Tx, and two supporting 16-bit autoreload/capture registers, RxA and RxB. Each timer block has two pins associated with it, TxA and TxB. The pin TxA supports I/O required by the timer block, while the pin TxB is an input to the timer block. The powerful and flexible timer block allows the device to easily perform all timer functions with minimal software overhead. The timer block has three operating modes: Processor Independent PWM mode, External Event Counter mode, and Input Capture mode. The control bits TxC3, TxC2, and TxC1 allow selection of the different modes of operation. TL/DD/12520 – 11 FIGURE 8. Timer in PWM Mode Mode 2. External Event Counter Mode This mode is quite similar to the processor independent PWM mode described above. The main difference is that the timer, Tx, is clocked by the input signal from the TxA pin. The Tx timer control bits, TxC3, TxC2 and TxC1 allow the timer to be clocked either on a positive or negative edge from the TxA pin. Underflows from the timer are latched into the TxPNDA pending flag. Setting the TxENA control flag will cause an interrupt when the timer underflows. In this mode the input pin TxB can be used as an independent positive edge sensitive interrupt input if the TxENB control flag is set. The occurrence of a positive edge on the TxB input pin is latched into the TxPNDB flag. Mode 1. Processor Independent PWM Mode As the name suggests, this mode allows the device to generate a PWM signal with very minimal user intervention. The user only has to define the parameters of the PWM signal (ON time and OFF time). Once begun, the timer block will continuously generate the PWM signal completely independent of the microcontroller. The user software services the timer block only when the PWM parameters require updating. In this mode the timer Tx counts down at a fixed rate of tc. Upon every underflow the timer is alternately reloaded with the contents of supporting registers, RxA and RxB. The very first underflow of the timer causes the timer to reload from the register RxA. Subsequent underflows cause the timer to be reloaded from the registers alternately beginning with the register RxB. The Tx Timer control bits, TxC3, TxC2 and TxC1 set up the timer for PWM mode operation. Figure 9 shows a block diagram of the timer in External Event Counter mode. Note: The PWM output is not available in this mode since the TxA pin is being used as the counter input clock. Figure 8 shows a block diagram of the timer in PWM mode. The underflows can be programmed to toggle the TxA output pin. The underflows can also be programmed to generate interrupts. Underflows from the timer are alternately latched into two pending flags, TxPNDA and TxPNDB. The user must reset these pending flags under software control. Two control enable flags, TxENA and TxENB, allow the interrupts from the timer underflow to be enabled or disabled. Setting the timer enable flag TxENA will cause an interrupt when a timer underflow causes the RxA register to be reloaded into the timer. Setting the timer enable flag TxENB will cause an interrupt when a timer underflow causes the RxB register to be reloaded into the timer. Resetting the timer enable flags will disable the associated interrupts. Either or both of the timer underflow interrupts may be enabled. This gives the user the flexibility of interrupting once per PWM period on either the rising or falling edge of the PWM output. Alternatively, the user may choose to interrupt on both edges of the PWM output. http://www.national.com TL/DD/12520 – 12 FIGURE 9. Timer in External Event Counter Mode Mode 3. Input Capture Mode The device can precisely measure external frequencies or time external events by placing the timer block, Tx, in the input capture mode. In this mode, the timer Tx is constantly running at the fixed tc rate. The two registers, RxA and RxB, act as capture registers. Each register acts in conjunction with a pin. The register RxA acts in conjunction with the TxA pin and the register RxB acts in conjunction with the TxB pin. 12 Timers (Continued) The timer value gets copied over into the register when a trigger event occurs on its corresponding pin. Control bits, TxC3, TxC2 and TxC1, allow the trigger events to be specified either as a positive or a negative edge. The trigger condition for each input pin can be specified independently. The trigger conditions can also be programmed to generate interrupts. The occurrence of the specified trigger condition on the TxA and TxB pins will be respectively latched into the pending flags, TxPNDA and TxPNDB. The control flag TxENA allows the interrupt on TxA to be either enabled or disabled. Setting the TxENA flag enables interrupts to be generated when the selected trigger condition occurs on the TxA pin. Similarly, the flag TxENB controls the interrupts from the TxB pin. Underflows from the timer can also be programmed to generate interrupts. Underflows are latched into the timer TxC0 pending flag (the TxC0 control bit serves as the timer underflow interrupt pending flag in the Input Capture mode). Consequently, the TxC0 control bit should be reset when entering the Input Capture mode. The timer underflow interrupt is enabled with the TxENA control flag. When a TxA interrupt occurs in the Input Capture mode, the user must check both the TxPNDA and TxC0 pending flags in order to determine whether a TxA input capture or a timer underflow (or both) caused the interrupt. TL/DD/12520 – 13 FIGURE 10. Timer in Input Capture Mode TIMER CONTROL FLAGS The timers T1, T2 and T3 have indentical control structures. The control bits and their functions are summarized below. TxC0 Timer Start/Stop control in Modes 1 and 2 (Processor Independent PWM and External Event Counter), where 1 e Start, 0 e Stop Timer Underflow Interrupt Pending Flag in Mode 3 (Input Capture) TxPNDA Timer Interrupt Pending Flag TxPNDB Timer Interrupt Pending Flag TxENA Timer Interrupt Enable Flag TxENB Timer Interrupt Enable Flag 1 e Timer Interrupt Enabled 0 e Timer Interrupt Disabled TxC3 Timer mode control TxC2 Timer mode control TxC1 Timer mode control Figure 10 shows a block diagram of the timer in Input Capture mode. 13 http://www.national.com Timers (Continued) The timer mode control bits (TxC3, TxC2 and TxC1) are detailed below: Interrupt A Source Interrupt B Source Timer Counts On MODE 2 (External Event Counter) Timer Underflow Pos. TxB Edge TxA Pos. Edge 1 MODE 2 (External Event Counter) Timer Underflow Pos. TxB Edge TxA Neg. Edge 0 1 MODE 1 (PWM) TxA Toggle Autoreload RA Autoreload RB tc 1 0 0 MODE 1 (PWM) No TxA Toggle Autoreload RA Autoreload RB tc 0 1 0 MODE 3 (Capture) Captures: TxA Pos. Edge TxB Pos. Edge Pos. TxA Edge or Timer Underflow Pos. TxB Edge tc 1 1 0 MODE 3 (Capture) Captures: TxA Pos. Edge TxB Neg. Edge Pos. TxA Edge or Timer Underflow Neg. TxB Edge tc 0 1 1 MODE 3 (Capture) Captures: TxA Neg. Edge TxB Pos. Edge Neg. TxA Edge or Timer Underflow Pos. TxB Edge tc 1 1 1 MODE 3 (Capture) Captures: TxA Neg. Edge TxB Neg. Edge Neg. TxA Edge or Timer Underflow Neg. TxB Edge tc TxC3 TxC2 TxC1 Timer Mode 0 0 0 0 0 1 Power Save Modes figuration (since CKO becomes a dedicated output), and so may be used with an RC clock configuration. The third method of exiting the HALT mode is by pulling the RESET pin low. Since a crystal or ceramic resonator may be selected as the oscillator, the Wakeup signal is not allowed to start the chip running immediately since crystal oscillators and ceramic resonators have a delayed start up time to reach full amplitude and frequency stability. The IDLE timer is used to generate a fixed delay to ensure that the oscillator has indeed stabilized before allowing instruction execution. In this case, upon detecting a valid Wakeup signal, only the oscillator circuitry is enabled. The IDLE timer is loaded with a value of 256 and is clocked with the tc instruction cycle clock. The tc clock is derived by dividing the oscillator clock down by a factor of 10. The Schmitt trigger following the CKI inverter on the chip ensures that the IDLE timer is clocked only when the oscillator has a sufficiently large amplitude to meet the Schmitt trigger specifications. This Schmitt trigger is not part of the oscillator closed loop. The startup timeout from the IDLE timer enables the clock signals to be routed to the rest of the chip. If an RC clock option is being used, the fixed delay is introduced optionally. A control bit, CLKDLY, mapped as configuration bit G7, controls whether the delay is to be introduced or not. The delay is included if CLKDLY is set, and excluded if CLKDLY is reset. The CLKDLY bit is cleared on reset. The device offers the user two power save modes of operation: HALT and IDLE. In the HALT mode, all microcontroller activities are stopped. In the IDLE mode, the on-board oscillator circuitry the WATCHDOG logic, the Clock Monitor and timer T0 are active but all other microcontroller activities are stopped. In either mode, all on-board RAM, registers, I/O states, and timers (with the exception of T0) are unaltered. HALT MODE The device can be placed in the HALT mode by writing a ‘‘1’’ to the HALT flag (G7 data bit). All microcontroller activities, including the clock and timers, are stopped. The WATCHDOG logic is disabled during the HALT mode. However, the clock monitor circuitry if enabled remains active and will cause the WATCHDOG output pin (WDOUT) to go low. If the HALT mode is used and the user does not want to activate the WDOUT pin, the Clock Monitor should be disabled after the device comes out of reset (resetting the Clock Monitor control bit with the first write to the WDSVR register). In the HALT mode, the power requirements of the device are minimal and the applied voltage (VCC) may be decreased to Vr (Vr e 2.0V) without altering the state of the machine. The device supports three different ways of exiting the HALT mode. The first method of exiting the HALT mode is with the Multi-Input Wakeup feature on the L port. The second method is with a low to high transition on the CKO (G7) pin. This method precludes the use of the crystal clock con- http://www.national.com 14 Power Save Modes (Continued) The user has the option of being interrupted with a transition on the thirteenth bit of the IDLE Timer T0. The interrupt can be enabled or disabled via the T0EN control bit. Setting the T0EN flag enables the interrupt and vice versa. The user can enter the IDLE mode with the Timer T0 interrupt enabled. In this case, when the T0PND bit gets set, the device will first execute the Timer T0 interrupt service routine and then return to the instruction following the ‘‘Enter Idle Mode’’ instruction. Alternatively, the user can enter the IDLE mode with the IDLE Timer T0 interrupt disabled. In this case, the device will resume normal operation with the instruction immediately following the ‘‘Enter IDLE Mode’’ instruction. The device has two mask options associated with the HALT mode. The first mask option enables the HALT mode feature, while the second mask option disables the HALT mode. With the HALT mode enable mask option, the device will enter and exit the HALT mode as described above. With the HALT disable mask option, the device cannot be placed in the HALT mode (writing a ‘‘1’’ to the HALT flag will have no effect, the HALT flag will remain ‘‘0’’). IDLE MODE The device is placed in the IDLE mode by writing a ‘‘1’’ to the IDLE flag (G6 data bit). In this mode, all activities, except the associated on-board oscillator circuitry, the WATCHDOG logic, the clock monitor and the IDLE Timer T0, are stopped. As with the HALT mode, the device can be returned to normal operation with a reset, or with a Multi-Input Wakeup from the L Port. Alternately, the microcontroller resumes normal operation from the IDLE mode when the thirteenth bit (representing 4.096 ms at internal clock frequency of 1 MHz, tc e 1 ms) of the IDLE Timer toggles. This toggle condition of the thirteenth bit of the IDLE Timer T0 is latched into the T0PND pending flag. Note: It is necessary to program two NOP instructions following both the set HALT mode and set IDLE mode instructions. These NOP instructions are necessary to allow clock resynchronization following the HALT or IDLE modes. Multi-Input Wakeup The Multi-Input Wakeup feature is ued to return (wakeup) the device from either the HALT or IDLE modes. Alternately Multi-Input Wakeup/Interrupt feature may also be used to generate up to 8 edge selectable external interrupts. Figure 11 shows the Multi-Input Wakeup logic. TL/DD/12520 – 14 FIGURE 11. Multi-Input Wake Up Logic 15 http://www.national.com Multi-Input Wakeup (Continued) The occurrence of the selected trigger condition for Multi-Input Wakeup is latched into a pending register called WKPND. The respective bits of the WKPND register will be set on the occurrence of the selected trigger edge on the corresponding Port L pin. The user has the responsibility of clearing these pending flags. Since WKPND is a pending register for the occurrence of selected wakeup conditions, the device will not enter the HALT mode if any Wakeup bit is both enabled and pending. Consequently, the user has the responsibility of clearing the pending flags before attempting to enter the HALT mode. WKEN, WKPND and WKEDG are all read/write registers, and are cleared at reset. The Multi-Input Wakeup feature utilizes the L Port. The user selects which particular L port bit (or combination of L Port bits) will cause the device to exit the HALT or IDLE modes. The selection is done through the Reg: WKEN. The Reg: WKEN is an 8-bit read/write register, which contains a control bit for every L port bit. Setting a particular WKEN bit enables a Wakeup from the associated L port pin. The user can select whether the trigger condition on the selected L Port pin is going to be either a positive edge (low to high transition) or a negative edge (high to low transition). This selection is made via the Reg: WKEDG, which is an 8bit control register with a bit assigned to each L Port pin. Setting the control bit will select the trigger condition to be a negative edge on that particular L Port pin. Resetting the bit selects the trigger condition to be a positive edge. Changing an edge select entails several steps in order to avoid a pseudo Wakeup condition as a result of the edge change. First, the associated WKEN bit should be reset, followed by the edge select change in WKEDG. Next, the associated WKPND bit should be cleared, followed by the associated WKEN bit being re-enabled. An example may serve to clarify this procedure. Suppose we wish to change the edge select from positive (low going high) to negative (high going low) for L Port bit 5, where bit 5 has previously been enabled for an input interrupt. The program would be as follows: RBIT 5, WKEN SBIT 5, WKEDG RBIT 5, WKPND SBIT 5, WKEN If the L port bits have been used as outputs and then changed to inputs with Multi-Input Wakeup/Interrupt, a safety procedure should also be followed to avoid inherited pseudo wakeup conditions. After the selected L port bits have been changed from output to input but before the associated WKEN bits are enabled, the associated edge select bits in WKEDG should be set or reset for the desired edge selects, followed by the associated WKPND bits being cleared. This same procedure should be used following reset, since the L port inputs are left floating as a result of reset. http://www.national.com PORT L INTERRUPTS Port L provides the user with an additional eight fully selectable, edge sensitive interrupts which are all vectored into the same service subroutine. The interrupt from Port L shares logic with the wake up circuitry. The register WKEN allows interrupts from Port L to be individually enabled or disabled. The register WKEDG specifies the trigger condition to be either a positive or a negative edge. Finally, the register WKPND latches in the pending trigger conditions. The GIE (Global Interrupt Enable) bit enables the interrupt function. A control flag, LPEN, functions as a global interrupt enable for Port L interrupts. Setting the LPEN flag will enable interrupts and vice versa. A separate global pending flag is not needed since the register WKPND is adequate. Since Port L is also used for waking the device out of the HALT or IDLE modes, the user can elect to exit the HALT or IDLE modes either with or without the interrupt enabled. If he elects to disable the interrupt, then the device will restart execution from the instruction immediately following the instruction that placed the microcontroller in the HALT or IDLE modes. In the other case, the device will first execute the interrupt service routine and then revert to normal operation. (See HALT MODE for clock option wakeup information.) 16 Analog Function Block TL/DD/12520 – 15 FIGURE 12. COP87L88EK Analog Function Block CMPT2B This device contains an analog function block with the intent to provide a function which allows for single slope, low cost, A/D conversion of up to 6 channels. CMPSL REGISTER (ADDRESS X’00B7) The CMPSL register contains the following bits: CMPNEG Will drive I1 to a low level. This bit can be used to discharge an external capacitor. This bit is disabled if the comparator is not enabled (CMPEN e 0). CMPEN Enable the comparator (‘‘1’’ e enable). CSEN Enables the internal constant current source. This current source provides a nominal 20 mA constant current at the I1 pin. This current can be used to ensure a linear charging rate on an external capacitor. This bit has no affect and the current source is disabled if the comparator is not enabled (CMPEN e 0). Selects the timer T2B input to be driven directly by the comparator output. If the comparator is disabled (CMPEN e 0), this function is disabled, i.e., the T2B input is connected to Port L5. CMPT2B CMPISEL2 CMPISEL1 CMPISEL0 CMPOE CSEN CMPEN CMPNEG Bit 7 Bit 0 The Comparator Select Register is cleared on RESET (the comparator is disabled). To save power the program should also disable the comparator before the mC enters the HALT/IDLE modes. Disabling the comparator will turn off the constant current source and the VCC/2 reference, disconnect the comparator output from the T2B input and pin I3 or I7 and remove the low on I1 caused by CMPNEG. It is often useful for the user’s program to read the result of a comparator operation. Since I1 is always selected to be COMPINb when the comparator is enabled (CMPEN e 1), the comparator output can be read internally by reading bit 1 (CMPRD) of register PORTI (RAM address 0 x D7). The following table lists the comparator inputs and outputs vs. the value of the CMPISEL0/1/2 bits. The output will only be driven if the CMPOE bit is set to 1. CMPOE Enables the comparator output to either pin I3 or pin I7 (‘‘1’’ e enable) depending on the value of CMPISEL0/1/2. CMPISEL0/1/2 Will select one of seven possible sources (I0/I2/I3/I4/I5/I6/internal reference) as a positive input to the comparator (see Table I for more information.) 17 http://www.national.com Analog Function Block (Continued) TABLE I. Comparator Input Selection Control Bit Comparator Input Source Neg. Input Pos. Input Comparator Output CMPISEL2 CMPISEL1 CMPISEL0 0 0 0 I1 I2 I3 0 0 1 I1 I2 I7 0 1 0 I1 I3 I7 0 1 1 I1 I0 I7 1 0 0 I1 I4 I7 1 0 1 I1 I5 I7 1 1 0 I1 I6 I7 1 1 1 I1 VCC/2 Ref. I7 ranking and the memory locations reserved for the interrupt vector for each source. Two bytes of program memory space are reserved for each interrupt source. All interrupt sources except the software interrupt are maskable. Each of the maskable interrupts have an Enable bit and a Pending bit. A maskable interrupt is active if its associated enable and pending bits are set. If GIE e 1 and an interrupt is active, then the processor will be interrupted as soon as it is ready to start executing an instruction except if the above conditions happen during the Software Trap service routine. This exception is described in the Software Trap sub-section. The interruption process is accomplished with the INTR instruction (opcode 00), which is jammed inside the Instruction Register and replaces the opcode about to be executed. The following steps are performed for every interrupt: 1. The GIE (Global Interrupt Enable) bit is reset. 2. The address of the instruction about to be executed is pushed into the stack. 3. The PC (Program Counter) branches to address 00FF. This procedure takes 7 tc cycles to execute. Reset The state of the Comparator Block immediately after RESET is as follows: 1. The CMPSL Register is set to all zeros 2. The Comparator is disabled 3. The Constant Current Source is disabled 4. CMPNEG is turned off 5. The Port I inputs are electrically isolated from the comparator 6. The T2B input is as normally selected by the T2CNTRL Register 7. CMPISEL0 – CMPISEL2 are set to zero 8. All Port I inputs are selected to the default digital input mode The comparator outputs have the same specification as Ports L and G except that the rise and fall times are symmetrical. Interrupts The device supports a vectored interrupt scheme. It supports a total of fourteen interrupt sources. The following table lists all the possible interrupt sources, their arbitration TL/DD/12520 – 16 FIGURE 13. Interrupt Block Diagram http://www.national.com 18 Interrupts (Continued) Arbitration Ranking Source Description INTR Instruction Vector* Address Hi-Low Byte (1) Highest Software (2) Reserved 0yFE – 0yFF (3) External G0 0yFA – 0yFB (4) Timer T0 Underflow 0yF8 – 0yF9 (5) Timer T1 T1A/Underflow 0yF6 – 0yF7 (6) Timer T1 T1B 0yF4 – 0yF5 (7) MICROWIRE/PLUS BUSY Low (8) Reserved 0yF0 – 0yF1 (9) Reserved 0yEE – 0yEF (10) Reserved (11) Timer T2 T2A/Underflow 0yEA – 0yEB (12) Timer T2 T2B 0yE8 – 0yE9 (13) Timer T3 T3A/Underflow 0yE6 – 0yE7 (14) Timer T3 T3B 0yE4 – 0yE5 (15) Port L/Wakeup Port L Edge 0yE2 – 0yE3 (16) Lowest Default VIS Instr. Execution without Any Interrupts 0yE0 – 0yE1 0yFC – 0yFD 0yF2 – 0yF3 0yEC – 0yED *y is a variable which represents the VIS block. VIS and the vector table must be located in the same 256-byte block except if VIS is located at the last address of a block. In this case, the table must be in the next block. tween 00FF and 01DF). The vectors are 15-bit wide and therefore occupy 2 ROM locations. VIS and the vector table must be located in the same 256byte block (0y00 to 0yFF) except if VIS is located at the last address of a block. In this case, the table must be in the next block. The vector table cannot be inserted in the first 256-byte block (y i 0). The vector of the maskable interrupt with the lowest rank is located at 0yE0 (Hi-Order byte) and 0yE1 (Lo-Order byte) and so forth in increasing rank number. The vector of the maskable interrupt with the highest rank is located at 0yFA (Hi-Order byte) and 0yFB (Lo-Order byte). The Software Trap has the highest rank and its vector is located at 0yFE and 0yFF. If, by accident, a VIS gets executed and no interrupt is active, then the PC (Program Counter) will branch to a vector located at 0yE0 – 0yE1. WARNING A Default VIS interrupt handler routine must be present. As a minimum, this handler should confirm that the GIE bit is cleared (this indicates that the interrupt sequence has been taken), take care of any required housekeeping, restore context and return. Some sort of Warm Restart procedure should be implemented. These events can occur without any error on the part of the system designer or programmer. At this time, since GIE e 0, other maskable interrupts are disabled. The user is now free to do whatever context switching is required by saving the context of the machine in the stack with PUSH instructions. The user would then program a VIS (Vector Interrupt Select) instruction in order to branch to the interrupt service routine of the highest priority interrupt enabled and pending at the time of the VIS. Note that this is not necessarily the interrupt that caused the branch to address location 00FF Hex prior to the context switching. Thus, if an interrupt with a higher rank than the one which caused the interruption becomes active before the decision of which interrupt to service is made by the VIS, then the interrupt with the higher rank will override any lower ones and will be acknowledged. The lower priority interrupt(s) are still pending, however, and will cause another interrupt immediately following the completion of the interrupt service routine associated with the higher priority interrupt just serviced. This lower priority interrupt will occur immediately following the RETI (Return from Interrupt) instruction at the end of the interrupt service routine just completed. Inside the interrupt service routine, the associated pending bit has to be cleared by software. The RETI (Return from Interrupt) instruction at the end of the interrupt service routine will set the GIE (Global Interrupt Enable) bit, allowing the processor to be interrupted again if another interrupt is active and pending. The VIS instruction looks at all the active interrupts at the time it is executed and performs an indirect jump to the beginning of the service routine of the one with the highest rank. The addresses of the different interrupt service routines, called vectors, are chosen by the user and stored in ROM in a table starting at 01E0 (assuming that VIS is located be- Note: There is always the possibility of an interrupt occurring during an instruction which is attempting to reset the GIE bit or any other interrupt enable bit. If this occurs when a single cycle instruction is being used to reset the interrupt enable bit, the interrupt enable bit will be reset but an interrupt may still occur. This is because interrupt processing is started at the same time as the interrupt bit is being reset. To avoid this scenario, the user should always use a two, three, or four cycle instruction to reset interrupt enable bits. Figure 13 shows the Interrupt block diagram. 19 http://www.national.com Interrupts (Continued) TABLE III. WATCHDOG Service Window Select SOFTWARE TRAP The Software Trap (ST) is a special kind of non-maskable interrupt which occurs when the INTR instruction (used to acknowledge interrupts) is fetched from ROM and placed inside the instruction register. This may happen when the PC is pointing beyond the available ROM address space or when the stack is over-popped. When an ST occurs, the user can re-initialize the stack pointer and do a recovery procedure (similar to reset, but not necessarily containing all of the same initialization procedures) before restarting. The occurrence of an ST is latched into the ST pending bit. The GIE bit is not affected and the ST pending bit (not accessible by the user) is used to inhibit other interrupts and to direct the program to the ST service routine with the VIS instruction. The RPND instruction is used to clear the software interrupt pending bit. This pending bit is also cleared on reset. The ST has the highest rank among all interrupts. Nothing (except another ST) can interrupt an ST being serviced. X 0 1 1 0 Y 7 6 5 4 3 2 1 0 The lower limit of the service window is fixed at 2048 instruction cycles. Bits 7 and 6 of the WDSVR register allow the user to pick an upper limit of the service window. Table III shows the four possible combinations of lower and upper limits for the WATCHDOG service window. This flexibility in choosing the WATCHDOG service window prevents any undue burden on the user software. Bits 5, 4, 3, 2 and 1 of the WDSVR register represent the 5bit Key Data field. The key data is fixed at 01100. Bit 0 of the WDSVR Register is the Clock Monitor Select bit. http://www.national.com 2k –8k tc Cycles 2k – 16k tc Cycles 2k – 32k tc Cycles 2k – 64k tc Cycles The WATCHDOG and Clock Monitor are disabled during reset. The device comes out of reset with the WATCHDOG armed, the WATCHDOG Window Select bits (bits 6, 7 of the WDSVR Register) set, and the Clock Monitor bit (bit 0 of the WDSVR Register) enabled. Thus, a Clock Monitor error will occur after coming out of reset, if the instruction cycle clock frequency has not reached a minimum specified value, including the case where the oscillator fails to start. The WDSVR register can be written to only once after reset and the key data (bits 5 through 1 of the WDSVR Register) must match to be a valid write. This write to the WDSVR register involves two irrevocable choices: (i) the selection of the WATCHDOG service window (ii) enabling or disabling of the Clock Monitor. Hence, the first write to WDSVR Register involves selecting or deselecting the Clock Monitor, select the WATCHDOG service window and match the WATCHDOG key data. Subsequent writes to the WDSVR register will compare the value being written by the user to the WATCHDOG service window value and the key data (bits 7 through 1) in the WDSVR Register. Table IV shows the sequence of events that can occur. The user must service the WATCHDOG at least once before the upper limit of the service window expires. The WATCHDOG may not be serviced more than once in every lower limit of the service window. The user may service the WATCHDOG as many times as wished in the time period between the lower and upper limits of the service window. The first write to the WDSVR Register is also counted as a WATCHDOG service. The WATCHDOG has an output pin associated with it. This is the WDOUT pin, on pin 1 of the port G. WDOUT is active low. The WDOUT pin is in the high impedance state in the inactive state. Upon triggering the WATCHDOG, the logic will pull the WDOUT (G1) pin low for an additional 16 tc –32 tc cycles after the signal level on WDOUT pin goes below the lower Schmitt trigger threshold. After this delay, the device will stop forcing the WDOUT output low. The WATCHDOG service window will restart when the WDOUT pin goes high. It is recommended that the user tie the WDOUT pin back to VCC through a resistor in order to pull WDOUT high. Clock Monitor 0 0 1 0 1 WATCHDOG Operation TABLE II. WATCHDOG Service Register (WDSVR) X 0 0 1 1 Service Window (Lower-Upper Limits) The Clock Monitor aboard the device can be selected or deselected under program control. The Clock Monitor is guaranteed not to reject the clock if the instruction cycle clock (1/tc) is greater or equal to 10 kHz. This equates to a clock input rate on CKI of greater or equal to 100 kHz. The device contains a WATCHDOG and clock monitor. The WATCHDOG is designed to detect the user program getting stuck in infinite loops resulting in loss of program control or ‘‘runaway’’ programs. The Clock Monitor is used to detect the absence of a clock or a very slow clock below a specified rate on the CKI pin. The WATCHDOG consists of two independent logic blocks: WD UPPER and WD LOWER. WD UPPER establishes the upper limit on the service window and WD LOWER defines the lower limit of the service window. Servicing the WATCHDOG consists of writing a specific value to a WATCHDOG Service Register named WDSVR which is memory mapped in the RAM. This value is composed of three fields, consisting of a 2-bit Window Select, a 5-bit Key Data field, and the 1-bit Clock Monitor Select field. Table II shows the WDSVR register. Key Data WDSVR Bit 6 Clock Monitor WATCHDOG Window Select WDSVR Bit 7 20 WATCHDOG Operation (Continued) # The WATCHDOG detector circuit is inhibited during both A WATCHDOG service while the WDOUT signal is active will be ignored. The state of the WDOUT pin is not guaranteed on reset, but if it powers up low then the WATCHDOG will time out and WDOUT will enter high impedance state. The Clock Monitor forces the G1 pin low upon detecting a clock frequency error. The Clock Monitor error will continue until the clock frequency has reached the minimum specified value, after which the G1 output will enter the high impedance TRI-STATE mode following 16 tc – 32 tc clock cycles. The Clock Monitor generates a continual Clock Monitor error if the oscillator fails to start, or fails to reach the minimum specified frequency. The specification for the Clock Monitor is as follows: 1/tc l 10 kHzÐNo clock rejection. the HALT and IDLE modes. # The CLOCK MONITOR detector circuit is active during both the HALT and IDLE modes. Consequently, the device inadvertently entering the HALT mode will be detected as a CLOCK MONITOR error (provided that the CLOCK MONITOR enable option has been selected by the program). # With the single-pin R/C oscillator mask option selected and the CLKDLY bit reset, the WATCHDOG service window will resume following HALT mode from where it left off before entering the HALT mode. # With the crystal oscillator mask option selected, or with the single-pin R/C oscillator mask option selected and the CLKDLY bit set, the WATCHDOG service window will be set to its selected value from WDSVR following HALT. Consequently, the WATCHDOG should not be serviced for at least 2048 instruction cycles following HALT, but must be serviced within the selected window to avoid a WATCHDOG error. 1/tc k 10 HzÐGuaranteed clock rejection. WATCHDOG AND CLOCK MONITOR SUMMARY The following salient points regarding the WATCHDOG and CLOCK MONITOR should be noted: # Both the WATCHDOG and CLOCK MONITOR detector circuits are inhibited during RESET. # The IDLE timer T0 is not initialized with RESET. # The user can sync in to the IDLE counter cycle with an # Following RESET, the WATCHDOG and CLOCK MONITOR are both enabled, with the WATCHDOG having he maximum service window selected. IDLE counter (T0) interrupt or by monitoring the T0PND flag. The T0PND flag is set whenever the thirteenth bit of the IDLE counter toggles (every 4096 instruction cycles). The user is responsible for resetting the T0PND flag. # The WATCHDOG service window and CLOCK MONITOR enable/disable option can only be changed once, during the initial WATCHDOG service following RESET. # A hardware WATCHDOG service occurs just as the de- # The initial WATCHDOG service must match the key data vice exits the IDLE mode. Consequently, the WATCHDOG should not be serviced for at least 2048 instruction cycles following IDLE, but must be serviced within the selected window to avoid a WATCHDOG error. value in the WATCHDOG Service register WDSVR in order to avoid a WATCHDOG error. # Subsequent WATCHDOG services must match all three # Following RESET, the initial WATCHDOG service (where data fields in WDSVR in order to avoid WATCHDOG errors. the service window and the CLOCK MONITOR enable/ disable must be selected) may be programmed anywhere within the maximum service window (65,536 instruction cycles) initialized by RESET. Note that this initial WATCHDOG service may be programmed within the initial 2048 instruction cycles without causing a WATCHDOG error. # The correct key data value cannot be read from the WATCHDOG Service register WDSVR. Any attempt to read this key data value of 01100 from WDSVR will read as key data value of all 0’s. 21 http://www.national.com Detection of Illegal Conditions MICROWIRE/PLUS The device can detect various illegal conditions resulting from coding errors, transient noise, power supply voltage drops, runaway programs, etc. MICROWIRE/PLUS is a serial synchronous communications interface. The MICROWIRE/PLUS capability enables the device to interface with any of National Semiconductor’s MICROWIRE peripherals (i.e. A/D converters, display drivers, E2PROMs etc.) and with other microcontrollers which support the MICROWIRE interface. It consists of an 8-bit serial shift register (SIO) with serial data input (SI), serial data output (SO) and serial shift clock (SK). Figure 14 shows a block diagram of the MICROWIRE/PLUS logic. Reading of undefined ROM gets zeros. The opcode for software interrupt is zero. If the program fetches instructions from undefined ROM, this will force a software interrupt, thus signaling that an illegal condition has occurred. The subroutine stack grows down for each call (jump to subroutine), interrupt, or PUSH, and grows up for each return or POP. The stack pointer is initialized to RAM location 06F Hex during reset. Consequently, if there are more returns than calls, the stack pointer will point to addresses 070 and 071 Hex (which are undefined RAM). Undefined RAM from addresses 070 to 07F (Segment 0), 140 to 17F (Segment 1), and all other segments (i.e., Segments 2 . . . etc.) is read as all 1’s, which in turn will cause the program to return to address 7FFF Hex. This is an undefined ROM location and the instruction fetched (all 0’s) from this location will generate a software interrupt signaling an illegal condition. Thus, the chip can detect the following illegal conditions: a. Executing from undefined ROM b. Over ‘‘POP’’ing the stack by having more returns than calls. When the software interrupt occurs, the user can re-initialize the stack pointer and do a recovery procedure before restarting (this recovery program is probably similar to that following reset, but might not contain the same program initialization procedures). The recovery program should reset the software interrupt pending bit using the RPND instruction. TL/DD/12520 – 17 FIGURE 14. MICROWIRE/PLUS Block Diagram The shift clock can be selected from either an internal source or an external source. Operating the MICROWIRE/ PLUS arrangement with the internal clock source is called the Master mode of operation. Similarly, operating the MICROWIRE/PLUS arrangement with an external shift clock is called the Slave mode of operation. The CNTRL register is used to configure and control the MICROWIRE/PLUS mode. To use the MICROWIRE/PLUS, the MSEL bit in the CNTRL register is set to one. In the master mode, the SK clock rate is selected by the two bits, SL0 and SL1, in the CNTRL register. Table V details the different clock rates that may be selected. TABLE IV. WATCHDOG Service Actions Key Data Window Data Clock Monitor Action Valid Service: Restart Service Window Match Match Match Don’t Care Mismatch Don’t Care Error: Generate WATCHDOG Output Mismatch Don’t Care Don’t Care Error: Generate WATCHDOG Output Don’t Care Don’t Care Mismatch Error: Generate WATCHDOG Output TABLE V. MICROWIRE/PLUS Master Mode Clock Select http://www.national.com SL1 SL0 SK 0 0 1 0 1 x 2 c tc 4 c tc 8 c tc 22 Where tc is the instruction cycle clock MICROWIRE/PLUS (Continued) The user must set the BUSY flag immediately upon entering the Slave mode. This will ensure that all data bits sent by the Master will be shifted properly. After eight clock pulses the BUSY flag will be cleared and the sequence may be repeated. MICROWIRE/PLUS OPERATION Setting the BUSY bit in the PSW register causes the MICROWIRE/PLUS to start shifting the data. It gets reset when eight data bits have been shifted. The user may reset the BUSY bit by software to allow less than 8 bits to shift. If enabled, an interrupt is generated when eight data bits have been shifted. The device may enter the MICROWIRE/PLUS mode either as a Master or as a Slave. Figure 15 shows how two microcontroller devices and several peripherals may be interconnected using the MICROWIRE/PLUS arrangements. Alternate SK Phase Operation The device allows either the normal SK clock or an alternate phase SK clock to shift data in and out of the SIO register. In both the modes the SK is normally low. In the normal mode data is shifted in on the rising edge of the SK clock and the data is shifted out on the falling edge of the SK clock. The SIO register is shifted on each falling edge of the SK clock. In the alternate SK phase operation, data is shifted in on the falling edge of the SK clock and shifted out on the rising edge of the SK clock. A control flag, SKSEL, allows either the normal SK clock or the alternate SK clock to be selected. Resetting SKSEL causes the MICROWIRE/PLUS logic to be clocked from the normal SK signal. Setting the SKSEL flag selects the alternate SK clock. The SKSEL is mapped into the G6 configuration bit. The SKSEL flag will power up in the reset condition, selecting the normal SK signal. Warning: The SIO register should only be loaded when the SK clock is low. Loading the SIO register while the SK clock is high will result in undefined data in the SIO register. SK clock is normally low when not shifting. Setting the BUSY flag when the input SK clock is high in the MICROWIRE/PLUS slave mode may cause the current SK clock for the SIO shift register to be narrow. For safety, the BUSY flag should only be set when the input SK clock is low. MICROWIRE/PLUS Master Mode Operation In the MICROWIRE/PLUS Master mode of operation the shift clock (SK) is generated internally by the device. The MICROWIRE Master always initiates all data exchanges. The MSEL bit in the CNTRL register must be set to enable the SO and SK functions onto the G Port. The SO and SK pins must also be selected as outputs by setting appropriate bits in the Port G configuration register. Table VI summarizes the bit settings required for Master mode of operation. TABLE VI This table assumes that the control flag MSEL is set. G4 (SO) G5 (SK) Config. Bit Config. Bit MICROWIRE/PLUS Slave Mode Operation In the MICROWIRE/PLUS Slave mode of operation the SK clock is generated by an external source. Setting the MSEL bit in the CNTRL register enables the SO and SK functions onto the G Port. The SK pin must be selected as an input and the SO pin is selected as an output pin by setting and resetting the appropriate bits in the Port G configuration register. Table VI summarizes the settings required to enter the Slave mode of operation. 1 1 0 1 1 0 0 0 G4 Fun. SO G5 Fun. Operation Int. MICROWIRE/PLUS SK Master TRI- Int. MICROWIRE/PLUS STATE SK Master SO Ext. MICROWIRE/PLUS SK Slave TRI- Ext. MICROWIRE/PLUS STATE SK Slave TL/DD/12520 – 18 FIGURE 15. MICROWIRE/PLUS Application 23 http://www.national.com Memory Map All RAM, ports and registers (except A and PC) are mapped into data memory address space. Address S/ADD REG 0000 to 006F On-Chip RAM bytes (112 bytes) 0070 to 007F Unused RAM Address Space (Reads As All Ones) Unused RAM Address Space (Reads Undefined Data) xx80 to xxAF xxB0 xxB1 xxB2 xxB3 xxB4 xxB5 xxB6 xxB7 xxB8 to xxBF xxC0 xxC1 xxC2 xxC3 xxC4 xxC5 xxC6 xxC7 xxC8 xxC9 xxCA xxCB xxCC xxCD to xxCF http://www.national.com Address S/ADD REG Contents Timer T3 Lower Byte Timer T3 Upper Byte Timer T3 Autoload Register T3RA Lower Byte Timer T3 Autoload Register T3RA Upper Byte Timer T3 Autoload Register T3RB Lower Byte Timer T3 Autoload Register T3RB Upper Byte Timer T3 Control Register Comparator Select Register (CMPSL) Reserved xxD0 xxD1 xxD2 xxD3 xxD4 xxD5 xxD6 xxD7 xxD8 xxD9 xxDA xxDB xxDC xxDD to xxDF Port L Data Register Port L Configuration Register Port L Input Pins (Read Only) Reserved for Port L Port G Data Register Port G Configuration Register Port G Input Pins (Read Only) Port I Input Pins (Read Only) Port C Data Register Port C Configuration Register Port C Input Pins (Read Only) Reserved for Port C Port D Reserved xxE0 to xxE5 xxE6 xxEE xxEF Reserved Timer T1 Autoload Register T1RB Lower Byte Timer T1 Autoload Register T1RB Upper Byte ICNTRL Register MICROWIRE/PLUS Shift Register Timer T1 Lower Byte Timer T1 Upper Byte Timer T1 Autoload Register T1RA Lower Byte Timer T1 Autoload Register T1RA Upper Byte CNTRL Control Register PSW Register xxF0 to FB xxFC xxFD xxFE xxFF On-Chip RAM Mapped as Registers X Register SP Register B Register S Register 0100 to 017F On-Chip 128 RAM Bytes xxE7 Timer T2 Lower Byte Timer T2 Upper Byte Timer T2 Autoload Register T2RA Lower Byte Timer T2 Autoload Register T2RA Upper Byte Timer T2 Autoload Register T2RB Lower Byte Timer T2 Autoload Register T2RB Upper Byte Timer T2 Control Register WATCHDOG Service Register (Reg:WDSVR) MIWU Edge Select Register (Reg:WKEDG) MIWU Enable Register (Reg:WKEN) MIWU Pending Register (Reg:WKPND) Reserved Reserved Reserved Contents xxE8 xxE9 xxEA xxEB xxEC xxED Reading memory locations 0070H–007FH (Segment 0) will return all ones. Reading unused memory locations 0080H–00AFH (Segment 0) will return undefined data. Reading memory locations from other unused Segments (i.e., Segment 2, Segment 3, ... etc.) will return all ones. 24 Addressing Modes There are ten addressing modes, six for operand addressing and four for transfer of control. Indirect This mode is used with the JID instruction. The contents of the accumulator are used as a partial address (lower 8 bits of PC) for accessing a location in the program memory. The contents of this program memory location serve as a partial address (lower 8 bits of PC) for the jump to the next instruction. The VIS is a special case of the Indirect Transfer of Control addressing mode, where the double byte vector associated with the interrupt is transferred from adjacent addresses in the program memory into the program counter (PC) in order to jump to the associated interrupt service routine. OPERAND ADDRESSING MODES Register Indirect This is the ‘‘normal’’ addressing mode. The operand is the data memory addressed by the B pointer or X pointer. Register Indirect (with auto post increment or decrement of pointer) This addressing mode is used with the LD and X instructions. The operand is the data memory addressed by the B pointer or X pointer. This is a register indirect mode that automatically post increments or decrements the B or X register after executing the instruction. Direct The instruction contains an 8-bit address field that directly points to the data memory for the operand. Immediate The instruction contains an 8-bit immediate field as the operand. Short Immediate This addressing mode is used with the Load B Immediate instruction. The instruction contains a 4-bit immediate field as the operand. Indirect This addressing mode is used with the LAID instruction. The contents of the accumulator are used as a partial address (lower 8 bits of PC) for accessing a data operand from the program memory. Instruction Set Register and Symbol Definition Registers A B X S SP PC PU PL C HC GIE VU VL TRANSFER OF CONTROL ADDRESSING MODES Relative This mode is used for the JP instruction, with the instruction field being added to the program counter to get the new program location. JP has a range from b31 to a 32 to allow a 1-byte relative jump (JP a 1 is implemented by a NOP instruction). There are no ‘‘pages’’ when using JP, since all 15 bits of PC are used. 8-Bit Accumulator Register 8-Bit Address Register 8-Bit Address Register 8-Bit Segment Register 8-Bit Stack Pointer Register 15-Bit Program Counter Register Upper 7 Bits of PC Lower 8 Bits of PC 1 Bit of PSW Register for Carry 1 Bit of PSW Register for Half Carry 1 Bit of PSW Register for Global Interrupt Enable Interrupt Vector Upper Byte Interrupt Vector Lower Byte Symbols [B] [X] Absolute This mode is used with the JMP and JSR instructions, with the instruction field of 12 bits replacing the lower 12 bits of the program counter (PC). This allows jumping to any location in the current 4k program memory segment. MD Mem Meml Imm Reg Absolute Long This mode is used with the JMPL and JSRL instructions, with the instruction field of 15 bits replacing the entire 15 bits of the program counter (PC). This allows jumping to any location up to 32k in the program memory space. Bit w Ý 25 Memory Indirectly Addressed by B Register Memory Indirectly Addressed by X Register Direct Addressed Memory Direct Addressed Memory or [B] Direct Addressed Memory or [B] or Immediate Data 8-Bit Immediate Data Register Memory: Addresses F0 to FF (Includes B, X and SP) Bit Number (0 to 7) Loaded with Exchanged with http://www.national.com Instruction Set (Continued) INSTRUCTION SET ADD ADC A,Meml A,Meml ADD ADD with Carry SUBC A,Meml Subtract with Carry AND ANDSZ OR XOR IFEQ IFEQ IFNE IFGT IFBNE DRSZ SBIT RBIT IFBIT RPND A,Meml A,Imm A,Meml A,Meml MD,Imm A,Meml A,Meml A,Meml Logical AND Logical AND Immed., Skip if Zero Logical OR Logical EXclusive OR IF EQual IF EQual IF Not Equal IF Greater Than If B Not Equal Decrement Reg., Skip if Zero Set BIT Reset BIT IF BIT Reset PeNDing Flag A w A a Meml A w A a Meml a C, C w Carry HC w Half Carry A w A b MemI a C, C w Carry HC w Half Carry A w A and Meml Skip next if (A and Imm) e 0 A w A or Meml A w A xor Meml Compare MD and Imm, Do next if MD e Imm Compare A and Meml, Do next if A e Meml Compare A and Meml, Do next if A i Meml Compare A and Meml, Do next if A l Meml Do next if lower 4 bits of B i Imm Reg w Reg b 1, Skip if Reg e 0 1 to bit, Mem (bit e 0 to 7 immediate) 0 to bit, Mem If bit in A or Mem is true do next instruction Reset Software Interrupt Pending Flag X X LD LD LD LD LD A,Mem A,[X] A,Meml A,[X] B,Imm Mem,Imm Reg,Imm EXchange A with Memory EXchange A with Memory [X] LoaD A with Memory LoaD A with Memory [X] LoaD B with Immed. LoaD Memory Immed LoaD Register Memory Immed. A Ý Mem A Ý [X] A w Meml A w [X] B w Imm Mem w Imm Reg w Imm X X LD LD LD A, [B g ] A, [X g ] A, [B g ] A, [X g ] [B g ],Imm EXchange A with Memory [B] EXchange A with Memory [X] LoaD A with Memory [B] LoaD A with Memory [X] LoaD Memory [B] Immed. A Ý [B], (B w B g 1) A Ý [X], (X w g 1) A w [B], (B w B g 1) A w [X], (X w X g 1) [B] w Imm, (B w B g 1) CLR INC DEC LAID DCOR RRC RLC SWAP SC RC IFC IFNC POP PUSH A A A CLeaR A INCrement A DECrement A Load A InDirect from ROM Decimal CORrect A Rotate A Right thru C Rotate A Left thru C SWAP nibbles of A Set C Reset C IF C IF Not C POP the stack into A PUSH A onto the stack Aw0 AwA a 1 AwA b 1 A w ROM (PU,A) A w BCD correction of A (follows ADC, SUBC) C x A7 x . . . x A0 x C C w A7 w . . . w A0 w C A7 . . . A4 Ý A3 . . . A0 C w 1, HC w 1 C w 0, HC w 0 IF C is true, do next instruction If C is not true, do next instruction SP w SP a 1, A w [SP] [SP] w A, SP w SP b 1 Vector to Interrupt Service Routine Jump absolute Long Jump absolute Jump relative short Jump SubRoutine Long Jump SubRoutine Jump InDirect RETurn from subroutine RETurn and SKip RETurn from Interrupt Generate an Interrupt No OPeration PU w [VU], PL w [VL] PC w ii (ii e 15 bits, 0 to 32k) PC9 . . . 0 w i (i e 12 bits) PC w PC a r (r is b31 to a 32, except 1) [SP] w PL, [SPb1] w PU,SPb2, PC w ii [SP] w PL, [SPb1] w PU,SPb2, PC9 . . . 0 w i PL w ROM (PU,A) SP a 2, PL w [SP], PU w [SPb1] SP a 2, PL w [SP],PU w [SPb1] SP a 2, PL w [SP],PU w [SPb1],GIE w 1 [SP] w PL, [SPb1] w PU, SPb2, PC w 0FF PC w PC a 1 VIS JMPL JMP JP JSRL JSR JID RET RETSK RETI INTR NOP Ý Reg Ý,Mem Ý,Mem Ý,Mem A A A A A A Addr. Addr. Disp. Addr. Addr http://www.national.com 26 Instruction Execution Time Most instructions are single byte (with immediate addressing mode instructions taking two bytes). Most single byte instructions take one cycle time to execute. Skipped instructions require x number of cycles to be skipped, where x equals the number of bytes in the skipped instruction opcode. See the BYTES and CYCLES per INSTRUCTION table for details. Bytes and Cycles per Instruction The following table shows the number of bytes and cycles for each instruction in the format of byte/cycle. Arithmetic and Logic Instructions [B] Direct ADD ADC SUBC AND OR XOR IFEQ IFNE IFGT IFBNE DRSZ 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 3/4 3/4 3/4 3/4 3/4 3/4 3/4 3/4 3/4 SBIT RBIT IFBIT 1/1 1/1 1/1 3/4 3/4 3/4 RPND 1/1 Instructions Using A & C CLRA INCA DECA LAID DCOR RRCA RLCA SWAPA SC RC IFC IFNC PUSHA POPA ANDSZ Immed. 2/2 2/2 2/2 2/2 2/2 2/2 2/2 2/2 2/2 1/3 1/1 1/1 1/1 1/3 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/3 1/3 2/2 Transfer of Control Instructions JMPL JMP JP JSRL JSR JID VIS RET RETSK RETI INTR NOP 3/4 2/3 1/3 3/5 2/5 1/3 1/5 1/5 1/5 1/5 1/7 1/1 Memory Transfer Instructions Register Indirect X A,* LD A,* LD B, Imm LD B, Imm LD Mem, Imm LD Reg, Imm IFEQ MD, Imm [B] [X] 1/1 1/1 1/3 1/3 2/2 Direct Immed. 2/3 2/3 2/2 1/1 2/2 3/3 2/3 3/3 Register Indirect Auto Incr. & Decr. [B a , Bb] [X a , Xb] 1/2 1/2 1/3 1/3 (IF B k 16) (IF B l 15) 2/2 * e l Memory location addressed by B or X or directly. 27 http://www.national.com http://www.national.com 28 VIS RPND X A,[X] JPb11 JPb27 LD 0F4, Ý i DRSZ 0F4 JPb10 JPb26 LD 0F5, Ý i DRSZ 0F5 JPb25 LD 0F6, Ý i DRSZ 0F6 JPb24 LD 0F7, Ý i DRSZ 0F7 JPb9 JPb8 JPb19 LD 0FC, Ý i DRSZ 0FC JPb18 LD 0FD, Ý i DRSZ 0FD JPb17 LD 0FE, Ý i DRSZ 0FE JPb16 LD 0FF, Ý i DRSZ 0FF JPb3 JPb2 JPb1 JPb0 * LD A,[X] DIR LD Md,Ýi i is the immediate data Md is a directly addressed memory location * is an unused opcode Note: The opcode 60 Hex is also the opcode for IFBIT Ýi,A Where, DECA JPb20 LD 0FB, Ý i DRSZ 0FB LD A,[Xb] LD A,[Bb] LD [Bb],Ýi JPb4 * LD A,[B] JSRL JMPL RETI RET LD [B],Ýi LD B,Ýi RETSK POPA LD A,Md X A,Md IFNC INCA IFNE A,Ýi JPb21 LD 0FA, Ý i DRSZ 0FA LD A,[X a ] LD A,[B a ] LD [B a ],Ýi IFC OR A,[B] JPb5 IFEQ Md,Ýi 5 CLRA * * * LD B,Ý0B LD B,Ý0C LD B,Ý0D LD B,Ý0E SBIT 7,[B] SBIT 6,[B] SBIT 5,[B] SBIT 4,[B] SBIT 3,[B] SBIT 2,[B] SBIT 1,[B] SBIT 0,[B] RBIT 7,[B] RBIT 6,[B] RBIT 5,[B] RBIT 4,[B] RBIT 3,[B] RBIT 2,[B] RBIT 1,[B] RBIT 0,[B] IFBNE 9 IFBNE 8 IFBNE 7 IFBNE 6 IFBNE 5 IFBNE 4 IFBNE 3 IFBNE 2 IFBNE 1 IFBNE 0 4 LD B,Ý00 IFBNE 0F LD B,Ý01 IFBNE 0E LD B,Ý02 IFBNE 0D LD B,Ý03 IFBNE 0C LD B,Ý04 IFBNE 0B LD B,Ý05 IFBNE 0A LD B,Ý06 LD B,Ý07 IFBIT PUSHA LD B,Ý08 7,[B] XOR A,[B] IFBIT DCORA LD B,Ý09 6,[B] JPb22 LD 0F9, Ý i DRSZ 0F9 IFNE A,[B] 6 AND A,[B] IFBIT SWAPA LD B,Ý0A 5,[B] ADD A,[B] IFBIT 4,[B] IFGT A,[B] IFBIT 3,[B] IFEQ A,[B] IFBIT 2,[B] JPb6 LD A,Ýi OR A,Ýi XOR A,Ýi AND A,Ýi ADD A,Ýi IFGT A,Ýi IFEQ A,Ýi JPb23 LD 0F8, Ý i DRSZ 0F8 RLCA * X A,[B] JID 7 ADC A,[B] IFBIT ANDSZ LD B,Ý0F 0,[B] A, Ýi 8 Upper Nibble SUBC A, Ýi SUB A,[B] IFBIT 1,[B] ADC A,Ýi 9 JPb7 NOP * X A,[Bb] X A,[Xb] JPb12 JPb28 LD 0F3, Ý i DRSZ 0F3 LAID X A,[B a ] X A,[X a ] JPb13 JPb29 LD 0F2, Ý i DRSZ 0F2 RC A SC B * C JPb14 JPb30 LD 0F1, Ý i DRSZ 0F1 D RRCA E JPb15 JPb31 LD 0F0, Ý i DRSZ 0F0 F Opcode Table 1 JP a 9 JP a 8 JP a 7 JP a 6 JP a 5 JP a 4 JP a 3 JP a 2 INTR 0 JMP JP a 26 JP a 10 x900–x9FF JMP JP a 25 x800–x8FF JMP JP a 24 x700–x7FF JMP JP a 23 x600–x6FF JMP JP a 22 x500–x5FF JMP JP a 21 x400–x4FF JMP JP a 20 x300–x3FF JMP JP a 19 x200–x2FF JMP JP a 18 x100–x1FF JMP JP a 17 x000–x0FF 2 JSR JMP JP a 32 JP a 16 xF00–xFFF xF00–xFFF JSR JMP JP a 31 JP a 15 xE00–xEFF xE00–xEFF JSR JMP JP a 30 JP a 14 xD00–xDFF xD00–xDFF JSR JMP JP a 29 JP a 13 xC00–xCFF xC00–xCFF JSR JMP JP a 28 JP a 12 xB00–xBFF xB00–xBFF JSR JMP JP a 27 JP a 11 xA00–xAFF xA00–xAFF JSR x900–x9FF JSR x800–x8FF JSR x700–x7FF JSR x600–x6FF JSR x500–x5FF JSR x400–x4FF JSR x300–x3FF JSR x200–x2FF JSR x100–x1FF JSR x000–x0FF 3 F E D C B A 9 8 7 6 5 4 3 2 1 0 Lower Nibble Development Support # Full 4k frame synchronous trace memory. Address, in- SUMMARY struction, and 8 unspecified, circuit connectable trace lines. Display can be HLL source (e.g., C source), assembly or mixed. # iceMASTERTM : IM-COP8/400ÐFull feature in-circuit emulation for all COP8 products. A full set of COP8 Basic and Feature Family device and package specific probes are available. # A full 64k hardware configurable break, trace on, trace off control, and pass count increment events. # COP8 Debug Module: Moderate cost in-circuit emulation # Tool set integrated interactive symbolic debuggerÐsup- and development programming unit. ports both assembler (COFF) and C Compiler (.COD) linked object formats. # COP8 Evaluation and Programming Unit: EPUCOP888GGÐlow cost In-circuit simulation and development programming unit. # Real time performance profiling analysis; selectable bucket definition. # Assembler: COP8-DEV-IBMA. A DOS installable cross development Assembler, Linker, Librarian and Utility Software Development Tool Kit. # Watch windows, content updated automatically at each # C Compiler: COP8C. A DOS installable cross develop- # Instruction by instruction memory/register changes dis- execution break. ment Software Tool Kit. played on source window when in single step operation. # OTP/EPROM Programmer Support: Covering needs # Single base unit and debugger software reconfigurable to from engineering prototype, pilot production to full production environments. support the entire COP8 family; only the probe personality needs to change. Debugger software is processor customized, and reconfigured from a master model file. iceMASTER (IM) IN-CIRCUIT EMULATION The iceMASTER IM-COP8/400 is a full feature, PC based, in-circuit emulation tool developed and marketed by MetaLink Corporation to support the whole COP8 family of products. National is a resale vendor for these products. See Figure 16 for configuration. # Processor specific symbolic display of registers and bit level assignments, configured from master model file. # Halt/Idle mode notification. # On-line HELP customized to specific processor using master model file. # Includes a copy of COP8-DEV-IBMA assembler and link- The iceMASTER IM-COP8/400 with its device specific COP8 Probe provides a rich feature set for developing, testing and maintaining product: er SDK. IM Order Information # Real-time in-circuit emulation; full 2.4V–5.5V operation Base Unit range, full DC-10 MHz clock. Chip options are programmable or jumper selectable. IM-COP8/400-1 iceMASTER Base Unit, 110V Power Supply IM-COP8/400-2 iceMASTER Base Unit, 220V Power Supply # Direct connection to application board by package compatible socket or surface mount assembly. # Full 32 kbytes of loadable programming space that overlays (replaces) the on-chip ROM or EPROM. On-chip RAM and I/O blocks are used directly or recreated on the probe as necessary. iceMASTER Probe MHW-884EK28DWPC 28 DIP MHW-888EK40DWPC 40 DIP MHW-888EK44PWPC 44 PLCC 28 DIP to 28 SO Adapter MHW-SOIC28 28 SO FIGURE 16. COP8 iceMASTER Environment TL/DD/12520 – 19 29 http://www.national.com Development Support (Continued) # Instruction by instruction memory/register changes dis- iceMASTER DEBUG MODULE (DM) played when in single step operation. The iceMASTER Debug Module is a PC based, combination in-circuit emulation tool and COP8 based OTP/EPROM programming tool developed and marketed by MetaLink Corporation to support the whole COP8 family of products. National is a resale vendor for these products. See Figure 17 for configuration. # Debugger software is processor customized, and reconfigured from a master model file. # Processor specific symbolic display of registers and bit level assignments, configured from master model file. # Halt/Idle mode notification. # Programming menu supports full product line of program- The iceMASTER Debug Module is a moderate cost development tool. It has the capability of in-circuit emulation for a specific COP8 microcontroller and in addition serves as a programming tool for COP8 OTP and EPROM product families. Summary of features is as follows: mable OTP and EPROM COP8 products. Program data is taken directly from the overlay RAM. # Programming of 44 PLCC and 68 PLCC parts requires external programming adapters. # Real-time in-circuit emulation; full operating voltage # Includes wall mount power supply. # On-board VPP generator from 5V input or connection to range operation, full DC-10 MHz clock. # All processor I/O pins can be cabled to an application external supply supported. Requires VPP level adjustment per the family programming specification (correct level is provided on an on-screen pop-down display). development board with package compatible cable to socket and surface mount assembly. # Full 32 kbytes of loadable programming space that over- # On-line HELP customized to specific processor using lays (replaces) the on-chip ROM or EPROM. On-chip RAM and I/O blocks are used directly or recreated as necessary. master model file. # Includes a copy of COP8-DEV-IBMA assembler and linker SDK. # 100 frames of synchronous trace memory. The display DM Order Information can be HLL source (C source), assembly or mixed. The most recent history prior to a break is available in the trace memory. Debug Model Unit COP8-DM/888EK # Configured break points; uses INTR instruction which is modestly intrusive. Cable Adapters # SoftwareÐonly supported features are selectable. # Tool set integrated interactive symbolic debuggerÐsupports both assembler (COFF) and C Compiler (.COD) SDK linked object formats. DM-COP8/28D 28 DIP DM-COP8/40D 40 DIP DM-COP8/44P 44 PLCC 28 DIP to 28 SO Adapter DM-COP8/28D-SO 28 SO TL/DD/12520 – 20 FIGURE 17. COP8-DM Environment http://www.national.com 30 Development Support (Continued) COP8 C COMPILER COP8 ASSEMBLER/LINKER SOFTWARE DEVELOPMENT TOOL KIT National Semiconductor offers a relocatable COP8 macro cross assembler, linker, librarian and utility software development tool kit. Features are summarized as follows: A C Compiler is developed and marketed by Byte Craft Limited. The COP8C compiler is a fully integrated development tool specifically designed to support the compact embedded configuration of the COP8 family of products. Features are summarized as follows: # Basic and Feature Family instruction set by ‘‘device’’ type. # ANSI C with some restrictions and extensions that opti- # # # # # # # mize development for the COP8 embedded application. Nested macro capability. Extensive set of assembler directives. Supported on PC/DOS platform. Generates National standard COFF output files. Integrated Linker and Librarian. Integrated utilities to generate ROM code file outputs. DUMPCOFF utility. This product is integrated as a part of MetaLink tools as a development kit, fully supported by the MetaLink debugger. It may be ordered separately or it is bundled with the MetaLink products at no additional cost. # BITS data type extension. Register declaration Ýpragma with direct bit level definitions. # C language support for interrupt routines. # Expert system, rule based code generation and optimization. # Performs consistency checks against the architectural definitions of the target COP8 device. # Generates program memory code. # Supports linking of compiled object or COP8 assembled object formats. # Global optimization of linked code. # Symbolic debug load format fully sourced level support- Order Information ed by the MetaLink debugger. Assembler SDK COP8-DEV-IBMA OTP/EMULATOR SUPPORT The COP87L88EK/COP87L84EK devices provide emulation and OTP support for the COP888EK/COP884EK mask programmable devices. Assembler SDK on installable 3.5× PC/DOS Floppy Disk Drive format. Periodic upgrades and most recent version is available on National’s BBS and Internet. Approved List Manufacturer North America Europe Asia BP Microsystems (800) 225-2102 (713) 688-4600 Fax: (713) 688-0920 a 49-8152-4183 a 49-8856-932616 a 852-234-16611 a 852-2710-8121 Data I/O (800) 426-1045 (206) 881-6444 Fax: (206) 882-1043 a 44-0734-440011 Call North America HI–LO (510) 623-8860 Call Asia a 886-2-764-0215 Fax: a 886-2-756-6403 ICE Technology (800) 624-8949 (919) 430-7915 a 44-1226-767404 Fax: 0-1226-370-434 MetaLink (800) 638-2423 (602) 926-0797 Fax: (602) 693-0681 a 49-80 9156 96-0 Fax: a 49-80 9123 86 a 852-737-1800 Systems General (408) 263-6667 a 41-1-9450300 a 886-2-917-3005 Fax: a 886-2-911-1283 Needhams (916) 924-8037 Fax: (916) 924-8065 31 http://www.national.com Development Support (Continued) DIAL-A-HELPER via FTP OTP Ordering Information Device Number COP87L88EKV-XE Clock Option ftp nscmicro.nsc.com Package Emulates user: password: Crystal/HALT En 44 PLCC COP888EK COP87L88EKN-XE Crystal/HALT En 40 DIP COP87L84EKN-XE Crystal/HALT En 28 DIP COP884EK COP87L84EKM-XE Crystal/HALT En 28 SO COP884EK DIAL-A-HELPER via a WorldWide Web Browser ftp://nscmicro.nsc.com COP888EK National Semiconductor on the WorldWide Web See us on the WorldWide Web at: http://www.natsemi.com *Check with the local sales office about the availability. CUSTOMER RESPONSE CENTER Complete product information and technical support is available from National’s customer response centers. INDUSTRY WIDE OTP/EPROM PROGRAMMING SUPPORT Programming support, in addition to the MetaLink development tools, is provided by a full range of independent approved vendors to meet the needs from the engineering laboratory to full production. CANADA/US: Tel: support email: europe.support @ nsc.com Deutsch Tel: a 49 (0) 180-530 85 85 English Tel: a 49 (0) 180-532 78 32 Fran3ais Tel: a 49 (0) 180-532 93 58 Italiano Tel: a 49 (0) 180-534 16 80 JAPAN: Tel: a 81-043-299-2309 S.E. ASIA: Beijing Tel: ( a 86) 10-6856-8601 Shanghai Tel: ( a 86) 21-6415-4092 EUROPE: DIAL-A-HELPER SERVICE Dial-A-Helper is a service provided by the Microcontroller Applications group. The Dial-A-Helper is an Electronic Information System that may be accessed as a Bulletin Board System (BBS) via data modem, as an FTP site on the Internet via standard FTP client application or as an FTP site on the Internet using a standard Internet browser such as Netscape or Mosaic. The Dial-A-Helper system provides access to an automated information storage and retrieval system. The system capabilities include a MESSAGE SECTION (electronic mail, when accessed as a BBS) for communications to and from the Microcontroller Applications Group and a FILE SECTION which consists of several file areas where valuable application software and utilities could be found. Modem: CANADA/U.S.: (800) NSC-MICRO (800) 672-6427 EUROPE: ( a 49) 0-8141-351332 http://www.national.com @ tevm2.nsc.com Hong Kong Tel: ( a 852) 2737-1600 DIAL-A-HELPER BBS via a Standard Modem Operation: (800) 272-9959 email: AVAILABLE LITERATURE For more information, please see the COP8 Basic Family User’s Manual, Literature Number 620895, COP8 Feature Family User’s Manual, Literature Number 620897 and National’s Family of 8-bit Microcontrollers COP8 Selection Guide, Literature Number 630009. Baud: Set-Up: anonymous username @ yourhost.site.domain 14.4k Length: 8-Bit Parity: None Stop Bit: 1 24 Hours, 7 Days 32 Korea Tel: ( a 82) 2-3771-6909 Malaysia Tel: ( a 60-4) 644-9061 Singapore Tel: ( a 65) 255-2226 Taiwan Tel: a 886-2-521-3288 AUSTRALIA: Tel: ( a 61) 3-9558-9999 INDIA: Tel: ( a 91) 80-559-9467 33 http://www.national.com Physical Dimensions inches (millimeters) unless otherwise noted Molded SO Wide Body Package (M) Order Number COP87L84EKM-XE NS Package Number M28B http://www.national.com 34 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Molded Dual-In-Line Package (N) Order Number COP87L84EKN-XE NS Package Number N28B Molded Dual-In-Line Package (N) Order Number COP87L84EKN-XE NS Package Number N40A 35 http://www.national.com COP87L88EK/COP87L84EK 8-Bit One Time Programmable (OTP) Microcontroller with Analog Function Block Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Plastic Leaded Chip Carrier (V) Order Number COP87L88EKV-XE NS Package Number V44A LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. National Semiconductor Corporation 1111 West Bardin Road Arlington, TX 76017 Tel: 1(800) 272-9959 Fax: 1(800) 737-7018 http://www.national.com 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. National Semiconductor Europe Fax: a49 (0) 180-530 85 86 Email: europe.support @ nsc.com Deutsch Tel: a49 (0) 180-530 85 85 English Tel: a49 (0) 180-532 78 32 Fran3ais Tel: a49 (0) 180-532 93 58 Italiano Tel: a49 (0) 180-534 16 80 National Semiconductor Hong Kong Ltd. 13th Floor, Straight Block, Ocean Centre, 5 Canton Rd. Tsimshatsui, Kowloon Hong Kong Tel: (852) 2737-1600 Fax: (852) 2736-9960 National Semiconductor Japan Ltd. Tel: 81-043-299-2308 Fax: 81-043-299-2408 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.