80C51FA/83C51FA EVENT-CONTROL CHMOS SINGLE-CHIP 8-BIT MICROCONTROLLER Automotive Y Extended Automotive Temperature Range ( b 40§ C to a 125§ C Ambient) Y Programmable Serial Channel with: Ð Framing Error Detection Ð Automatic Address Recognition Y High Performance CHMOS Process Y Y Three 16-Bit Timer/Counters Ð Timer 2 is an Up/Down Timer/Counter TTL and CMOS Compatible Logic Levels Y 64K External Program Memory Space Y 64K External Data Memory Space Y MCSÉ 51 Microcontroller Fully Compatible Instruction Set Y Power Saving Idle and Power Down Modes Y Programmable Counter Array with: Ð High Speed Output, Ð Compare/Capture, Ð Pulse Width Modulator, Ð Watchdog Timer Capabilities Y 8K On-Chip ROM Y ONCE (On-Circuit Emulation) Mode Y 256 Bytes of On-Chip Data RAM Y Available in PLCC and PDIP Packages Y Boolean Processor Y 32 Programmable I/O Lines Y 7 Interrupt Sources (See Packaging Specification, Order Ý231369) Y Available in 12 MHz and 16 MHz Versions MEMORY ORGANIZATION PROGRAM MEMORY: Up to 8 Kbytes of the program memory can reside in the on-chip ROM. In addition the device can address up to 64K of program memory external to the chip. DATA MEMORY: This microcontroller has a 256 x 8 on-chip RAM. In addition it can address up to 64 Kbytes of external data memory. The Intel 80C51FA/83C51FA is a single-chip control oriented microcontroller which is fabricated on Intel’s CHMOS III (83C51FA) ROM technology. For the remainder of this datasheet references to the ROMless (80C51FA) and ROM (83C51FA) versions will be denoted as 83C51FA. Being a member of the MCSÉ 51 microcontroller family, the 83C51FA uses the same powerful instruction set, has the same architecture, and is pin-for-pin compatible with the existing MCS 51 microcontroller products. The 83C51FA is an enhanced version of the 87C51. It’s added features make it an even more powerful microcontroller for applications that require Pulse Width Modulation, High Speed I/O, and up/down counting capabilities such as brake and traction control. It also has a more versatile serial channel that facilitates multi-processor communications. NOTICE: This datasheet contains information on products in full production. Specifications within this datasheet are subject to change without notice. Verify with your local Intel sales office that you have the latest datasheet before finalizing a design. *Other brands and names are the property of their respective owners. Information in this document is provided in connection with Intel products. Intel assumes no liability whatsoever, including infringement of any patent or copyright, for sale and use of Intel products except as provided in Intel’s Terms and Conditions of Sale for such products. Intel retains the right to make changes to these specifications at any time, without notice. Microcomputer Products may have minor variations to this specification known as errata. COPYRIGHT © INTEL CORPORATION, 1995 February 1995 Order Number: 270501-007 AUTOMOTIVE 80C51FA/83C51FA 270501 – 1 Figure 1. 83C51FA Block Diagram 2 AUTOMOTIVE 80C51FA/83C51FA 80C51FA/83C51FA PRODUCT OPTIONS Intel’s extended and automotive temperature range products are designed to meet the needs of those applications whose operating requirements exceed commercial standards. With the commercial standard temperature range, operational characteristics are guaranteed over the temperature range of 0§ C to 70§ C ambient. With the extended temperature range option, operational characteristics are guaranteed over the temperature range of b 40§ C to a 85§ C ambient. For the automotive temperature range option, operational characteristics are guaranteed over the temperature range of b 40§ C to a 125§ C ambient. As shown in Figure 2 temperature, burn-in, and package options are identified by a one- or two-letter prefix to the part number. 270501 – 2 *Example: AN83C51FA indicates an automotive temperature range version of the 83C51FA in a PLCC package with 8 Kbyte ROM program memory. Figure 2. MCSÉ 51 Microcontroller Product Family Nomenclature Table 1. Temperature Options Temperature Designation Operating Temperature § C Ambient Burn-In Options Extended T L b 40 to a 85 b 40 to a 85 Standard Extended Automotive A B b 40 to a 125 b 40 to a 125 Standard Extended Temperature Classification 3 AUTOMOTIVE 80C51FA/83C51FA PIN DESCRIPTIONS Port Pin Alternate Function VCC: Supply voltage. P1.0 T2 (External Count Input to Timer/ Counter 2) VSS: Circuit ground. P1.1 T2EX (Timer/Counter 2 Capture/ Reload Trigger and Direction Control) ECI (External Count Input to the PCA) Port 0: Port 0 is an 8-bit, open drain, bidirectional I/O port. As an output port each pin can sink several LS TTL inputs. Port 0 pins that have 1’s written to them float, and in that state can be used as high-impedance inputs. Port 0 is also the multiplexed low-order address and data bus during accesses to external Program and Data Memory. In this application it uses strong internal pullups when emitting1’s, and can source and sink several LS TTL inputs. Port 0 outputs the code bytes during program verification. External pullup resistors are required during program verification. Port 1: Port 1 is an 8-bit bidirectional I/O port with internal pullups. The Port 1 output buffers can drive LS TTL inputs. Port 1 pins that have 1’s written to them are pulled high by the internal pullups, and in that state can be used as inputs. As inputs, Port 1 pins that are externally pulled low will source current (IIL, on the datasheet) because of the internal pullups. In addition, Port 1 serves the functions of the following special features of the 83C51FA: P1.2 P1.3 CEX0 (External I/O for Compare/ Capture Module 0) P1.4 CEX1 (External I/O for Compare/ Capture Module 1) CEX2 (External I/O for Compare/ Capture Module 2) CEX3 (External I/O for Compare/ Capture Module 3) P1.5 P1.6 P1.7 CEX4 (External I/O for Compare/ Capture Module 4) Port 2: Port 2 is an 8-bit bidirectional I/O port with internal pullups. The Port 2 output buffers can drive LS TTL inputs. Port 2 pins that have 1’s written to them are pulled high by the internal pullups, and in that state can be used as inputs. As inputs, Port 2 pins that are externally pulled low will source current (IIL, on the datasheet) because of the internal pullups. Port 2 emits the high-order address byte during fetches from external Program Memory and during accesses to external Data Memory that use 16-bit addresses (MOVX @ DPTR). In this application it uses strong internal pullups when emitting 1’s. During accesses to external Data Memory that use 8-bit Pin (PDIP) Pad (PLCC) 270501 – 3 270501 – 4 **Do not connect reserved pins. Diagrams are for pin reference only. Package sizes are not to scale. Figure 3. Pin Connections 4 AUTOMOTIVE 80C51FA/83C51FA addresses (MOVX @ Ri), Port 2 emits the contents of the P2 Special Function Register. Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pullups. The Port 3 output buffers can drive LS TTL inputs. Port 3 pins that have 1’s written to them are pulled high by the internal pullups, and in that state can be used as inputs. As inputs, Port 3 pins that are externally pulled low will source current (IIL, on the datasheet) because of the pullups. EA/VPP: External Access enable. EA must be strapped to VSS in order to enable the device to fetch code from external Program Memory locations 0000H to 0FFFFH. Note, however, that if either of the Program Lock bits are programmed, EA will be internally latched on reset. EA should be strapped to VCC for internal program executions. XTAL1: Input to the inverting oscillator amplifier. Port 3 also serves the functions of various special features of the MCS 51 microcontroller family, as listed below: Port Pin Alternate Function P3.0 P3.1 P3.2 P3.3 P3.4 P3.5 P3.6 P3.7 RXD (serial input port) TXD (serial output port) INT0 (external interrupt 0) INT1 (external interrupt 1) T0 (Timer 0 external input) T1 (Timer 1 external input) WR (external data memory write strobe) RD (external data memory read strobe) RESET: Reset input. A high on this pin for two machine cycles while the oscillator is running resets the device. An internal pulldown resistor permits a power-on reset with only a capacitor connected to VCC. ALE/PROG: Address Latch Enable output pulse for latching the low byte of the address during accesses to external memory. In normal operation ALE is emitted at a constant rate of (/6 the oscillator frequency, and may be used for external timing or clocking purposes. Note, however, that one ALE pulse is skipped during each access to external Data Memory. XTAL2: Output from the inverting oscillator amplifier. OSCILLATOR CHARACTERISTICS XTAL1 and XTAL2 are the input and output, respectively, of a inverting amplifier which can be configured for use as an on-chip oscillator, as shown in Figure 4. Either a quartz crystal or ceramic resonator may be used. More detailed information concerning the use of the on-chip oscillator is available in Application Note AP-155, ‘‘Oscillators for Microcontrollers.’’ To drive the device from an external clock source, XTAL1 should be driven, while XTAL2 floats, as shown in Figure 5. There are no requirements on the duty cycle of the external clock signal, since the input to the internal clocking circuitry is through a divide-by-two flip-flop, but minimum and maximum high and low times specified on the datasheet must be observed. An external oscillator may encounter as much as a 100 pF load at XTAL1 when it starts up. This is due to interaction between the amplifier and its feedback capacitance. Once the external signal meets the VIL and VIH specifications the capacitance will not exceed 20 pF. Throughout the remainder of this datasheet, ALE will refer to the signal coming out of the ALE/PROG pin, and the pin will be referred to as the ALE/PROG pin. PSEN: Program Store Enable is the read strobe to external Program Memory. When the 83C51FA is executing code from external Program Memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external Data Memory. 270501 – 5 C1, C2 e 30 pF g 10 pF for Crystals For Ceramic Resonators, contact resonator manufacturer. Figure 4. Oscillator Connections 5 AUTOMOTIVE 80C51FA/83C51FA restored to its normal operating level and must be held active long enough for the oscillator to restart and stabilize (normally less than 10 ms). With an external interrupt, INT0 or INT1 must be enabled and configured as level-sensitive. Holding the pin low restarts the oscillator but bringing the pin back high completes the exit. Once the interrupt is serviced, the next instruction to be executed after RETI will be the one following the instruction that put the device into Power Down. 270501 – 6 Figure 5. External Clock Drive Configuration DESIGN CONSIDERATION IDLE MODE The user’s software can invoke the Idle Mode. When the microcontroller is in this mode, power consumption is reduced. The Special Function Registers and the onboard RAM retain their values during Idle, but the processor stops executing instructions. Idle Mode will be exited if the chip is reset or if an enabled interrupt occurs. The PCA timer/counter can optionally be left running or paused during Idle Mode. When the Idle mode is terminated by a hardware reset, the device normally resumes program execution, from where it left off, up to two machine cycles before the internal reset algorithm takes control. Onchip hardware inhibits access to internal RAM in this event, but access to the port pins is not inhibited. To eliminate the possibility of an unexpected write when Idle is terminated by reset, the instruction following the one that invokes Idle should not be one that writes to a port pin or to external memory. ONCE MODE POWER DOWN MODE To save even more power, a Power Down mode can be invoked by software. In this mode, the oscillator is stopped and the instruction that invoked Power Down is the last instruction executed. The on-chip RAM and Special Function Registers retain their values if the Power Down mode is terminated with an interrupt. On the 83C51FA either a hardware reset or external interrupt can cause an exit from Power Down. Reset redefines all the SFRs but does not change the onchip RAM. An external interrupt allows both the SFRs and the on-chip RAM to retain their values. To properly terminate Power Down the reset or external interrupt should not be executed before VCC is The ONCE (‘‘On-Circuit Emulation’’) Mode facilitates testing and debugging of systems using the 83C51FA without the 83C51FA having to be removed from the circuit. The ONCE Mode is invoked by: 1) Pull ALE low while the device is in reset and PSEN is high; 2) Hold ALE low as RST is deactivated. While the device is in ONCE Mode, the Port 0 pins float, the other port pins and ALE and PSEN are weakly pulled high. The oscillator circuit remains active. While the 83C51FA is in this mode, an emulator or test CPU can be used to drive the circuit. Normal operation is restored when a normal reset is applied. Table 2. Status of the External Pins during Idle and Power Down Program Memory ALE PSEN Idle Internal 1 1 Data Data Data Data Idle External 1 1 Float Data Address Data Power Down Internal 0 0 Data Data Data Data Power Down External 0 0 Float Data Data Data Mode PORT0 PORT1 PORT2 PORT3 NOTE: For more detailed information on the reduced power modes refer to current Embedded Applications Handbook, and Application Note AP-252, ‘‘Designing with the 80C51BH.’’ 6 AUTOMOTIVE 80C51FA/83C51FA ABSOLUTE MAXIMUM RATINGS* NOTICE: This is a production data sheet. The specifications are subject to change without notice. Ambient Temperature Under Bias ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ b 40§ C to a 125§ C Storage Temperature ÀÀÀÀÀÀÀÀÀÀ b 65§ C to a 150§ C Voltage on Any Other Pin to VSS ÀÀ b 0.5V to a 6.5V IOL I/O PinÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ15 mA *WARNING: Stressing the device beyond the ‘‘Absolute Maximum Ratings’’ may cause permanent damage. These are stress ratings only. Operation beyond the ‘‘Operating Conditions’’ is not recommended and extended exposure beyond the ‘‘Operating Conditions’’ may affect device reliability. Power DissipationÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ1.5W (Based on PACKAGE heat transfer limitations, not device power consumption) Typical Junction Temperature (TJ) ÀÀÀÀÀÀÀÀ a 135§ C (Based upon Ambient Temperature at a 125§ C) Typical Thermal Resistance Junction-to-Ambient (iJA) PDIP ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ45§ C/W PLCCÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ46§ C/W DC CHARACTERISTICS: Symbol (TA e b 40§ C to a 125§ C; VCC e 5V g 10%; VSS e 0V) Parameter VIL Input Low Voltage VIL1 Input Low Voltage EA VIH Input High Voltage (Except XTAL2, RST, EA) VIH1 Input High Voltage (XTAL, RST) VOL Max Unit b 0.5 Min Typ 0.2 VCC b 0.1 V Test Conditions 0 0.2 VCC b 0.3 V 0.2 VCC a 0.9 VCC a 0.5 V 0.7 VCC VCC a 0.5 V Output Low Voltage (Ports 1, 2 and 3) 0.45 V IOL e 1.6 mA(1) VOL1 Output Low Voltage (Port 0, ALE/PROG, PSEN) 0.45 V IOL e 20 IOL e 3.2 mA(1) IOL e 7.0 mA VOH Output High Voltage (Ports 1, 2 and 3 ALE/PROG and PSEN) 2.4 V IOH e b 60 mA 0.9 VCC V IOH e b 10 mA(2) 2.4 V IOH e b 800 mA 0.9 VCC V IOH e b 80 mA(2) VOH1 Output High Voltage (Port 0 in External Bus Mode) IIL Logical 0 Input Current (Ports 1, 2 and 3) b 10 b 50 mA VIN e 0.45V ILI Input leakage Current (Port 0) 0.02 g 10 mA VIN e VIL or VIH 7 AUTOMOTIVE 80C51FA/83C51FA DC CHARACTERISTICS: Symbol (TA e b 40§ C to a 125§ C; VCC e 5V g 10%; VSS e 0V) (Continued) Parameter ITL Logical 1 to 0 Transition Current (Ports 1, 2, and 3) RRST RST Pulldown Resistor CIO Pin Capacitance ICC Power Supply Current: Running at 12 MHz (Figure 5) Idle Mode at 12 MHz (Figure 5) Power Down Mode (IPD) Min 40 Typ Max Unit b 265 b 650 mA 100 225 KX 10 pF Test Conditions VIN e 2V @ 1MHz, 25§ C (Note 3) 40 15 150 mA mA mA NOTES: 1. Capacitive loading on Ports 0 and 2 may cause noise pulses to be superimposed on the VOLs of ALE and Ports 1 and 3. The noise is due to external bus capacitance discharging into the Port 0 and Port 2 pins when these pins make 1 to 0 transitions during bus operations. In applications where capacitance loading exceeds 100 pFs, the noise pulse on the ALE signal may exceed 0.8V. In these cases, it may be desirable to qualify ALE with a Schmitt Trigger, or use an Address Latch with a Schmitt Trigger Strobe input. 2. Capacitive loading on Ports 0 and 2 cause the VOH on ALE and PSEN to drop below the 0.9 VCC specification when the address lines are stabilizing. 3. See Figures 6–9 for test conditions. Minimum VCC for Power Down is 2.0V. 4. Typicals are based on limited number of samples, and are not guaranteed. The values listed are at room temperature and 5.0V. 5. Under steady state (non-transient) conditions, IOL must be externally limited as follows: 10 mA Maximum IOL per Port Pin: Maximum IOL per 8-Bit Port Port 0: 26 mA Ports 1, 2, and 3: 15 mA 71 mA Maximum Total IOL for all Output Pins: If IOL exceeds the test condition, VOL may exceed the related specification. Pins are not guaranteed to sink current greater than the listed test conditions. 6. Contact Intel for design-in information. 8 AUTOMOTIVE 80C51FA/83C51FA 270501 – 7 ICC Max at other frequencies is given by: Active Mode ICC Max e (3 c Osc Freq) a 4 Idle Mode ICC Max e (0.49 c Osc Freq) a 1.6 Where Osc Freq is in MHz, ICC is in mA. 270501 – 8 TCLCH e TCHCL e 5 ns Figure 7. ICC Test Condition, Active Mode All other pins disconnected. Figure 6. ICC vs Frequency 270501 – 10 270501 – 9 TCLCH e TCHCL e 5 ns Figure 8. ICC Test Condition Idle Mode. All other pins disconnected. Figure 9. ICC Test Condition, Power Down Mode. All other pins disconnected. VCC e 2.0V to 5.5V. 270501 – 11 Figure 10. Clock Signal Waveform for ICC Tests in Active and Idle Modes. TCLCH e TCHCL e 5 ns. 9 AUTOMOTIVE 80C51FA/83C51FA EXPLANATION OF THE AC SYMBOLS Each timing symbol has 5 characters. The first character is always a ‘T’ (stands for time). The other characters, depending on their positions, stand for the name of a signal or the logical status of that signal. The following is a list of all the characters and what they stand for. A: Address C: Clock D: Input Data H: Logic level HIGH I: Instruction (program memory contents) L: Logic level LOW, or ALE P: PSEN Q: Output Data R: RD signal T: Time V: Valid W: WR signal X: No longer a valid logic level Z: Float For example, TAVLL e Time from Address Valid to ALE Low TLLPL e Time from ALE Low to PSEN Low AC CHARACTERISTICS (TA e b 40§ C to a 125§ C, VCC e 5V g 10%, VSS e 0V, Load Capacitance for Port 0, ALE/PROG and PSEN e 100 pF, Load Capacitance for All Other Outputs e 80 pF) EXTERNAL MEMORY CHARACTERISTICS Symbol Parameter 12 MHz Oscillator Variable Oscillator Min Min Max 3.5 16 Max Units 1/TCLCL Oscillator Frequency TLHLL ALE Pulse Width 127 2TCLCL b 40 ns TAVLL Address Valid to ALE Low 43 TCLCL b 40 ns TLLAX Address Hold After ALE Low 53 TCLCL b 30 TLLIV ALE Low to Valid Instruction In TLLPL ALE Low to PSEN Low 53 TCLCL b 30 ns TPLPH PSEN Pulse Width 205 3TCLCL b 45 ns TPLIV PSEN Low to Valid Instruction In TPXIX Input Instr Hold After PSEN Trans TPXIZ Input Instr Float After PSEN Trans TAVIV TPLAZ TRLRH RD Pulse Width 400 6TCLCL b 100 TWLWH WR Pulse Width 400 6TCLCL b 100 224 ns 4TCLCL b 110 135 MHz ns 3TCLCL b 115 ns 59 TCLCL b 25 ns Address to Valid Instruction In 302 5TCLCL b 115 ns PSEN Low to Address Float 10 10 ns 0 0 ns ns TRLDV RD Low to Valid Data In TRHDX Data Hold After RD High TRHDZ Data Float After RD High 107 2TCLCL b 60 ns TLLDV ALE Low to Valid Data In 507 8TCLCL b 160 ns TAVDV Address Valid to Valid Data In 575 9TCLCL b 175 ns TLLWL ALE Low to RD or WR Low 200 TAVWL Data Valid to WR Low 203 4TCLCL b 130 ns TQVWX Address Valid before WR Low 23 TCLCL b 50 ns TWHQX Data Hold after WR High 33 TCLCL b 50 ns 433 7TCLCL b 150 TQVWH Data Valid to WE High TRLAZ RD Low to Address Float TWHLH RD or WR High to ALE High 10 242 ns b 10 ns b 10 300 3TCLCL b 50 0 43 5TCLCL b 175 123 TCLCL b 40 ns 3TCLCL a 50 ns ns 0 ns TCLCL a 40 ns AUTOMOTIVE 80C51FA/83C51FA EXTERNAL PROGRAM MEMORY READ CYCLE 270501 – 12 EXTERNAL DATA MEMORY READ CYCLE 270501 – 13 EXTERNAL DATA MEMORY WRITE CYCLE 270501 – 14 11 AUTOMOTIVE 80C51FA/83C51FA SERIAL PORT TIMINGÐSHIFT REGISTER MODE Test Conditions: TA e b 40§ C to a 125§ C; VCC e 5V g 10%; VSS e 0V; Load Capacitance e 80 pF 12 MHz Oscillator Variable Oscillator Parameter Units Min Max Min Max Symbol TXLXL Serial Port Clock Cycle Time 1 12TCLCL ms TQVXH Output Data Setup to Clock Rising Edge Output Data Hold after Clock Rising Edge 700 10TCLCL b 133 ns 50 2TCLCL b 117 ns Input Data Hold After Clock Rising Edge Clock Rising Edge to Input Data Valid 0 0 ns TXHQX TXHDX TXHDV 700 10TCLCL b 133 ns SHIFT REGISTER MODE TIMING WAVEFORMS 270501 – 15 EXTERNAL CLOCK DRIVE Symbol Parameter Min Max Units 1/TCLCL Oscillator Frequency 3.5 16 MHz TCHCX High Time 20 TCLCX Low Time 20 TCLCH Rise Time 20 ns TCHCL Fall Time 20 ns ns ns EXTERNAL CLOCK DRIVE WAVEFORM 270501 – 16 12 AUTOMOTIVE 80C51FA/83C51FA AC TESTING INPUT, OUTPUT WAVEFORMS 270501 – 17 AC Inputs during testing are driven at VCC b 0.5V for a Logic ‘‘1’’ and 0.45V for a Logic ‘‘0’’. Timing measurements are made at VIH min for a Logic ‘‘1’’ and VOL max for a Logic ‘‘0’’. FLOAT WAVEFORMS 270501 – 18 For timing purposes a port pin is no longer floating when a 100 mV change from load voltage occurs, and begins to float when a 100 mV change from the loaded VOH/VOL level occurs. IOL/IOH t g 20 mA. This is for Ports 1, 2 and 3. DATASHEET REVISION HISTORY The following are key differences between this datasheet and the -006 version: 1. The ‘‘preliminary’’ status was dropped and replaced with production status (no label). 2. Trademarks were updated. The following are key differences between the -006 and the -005 version of the datasheet: 1. Preliminary notice has been added to the Title page. 2. Figure 3 Pin Connections has been modified, RST pin is now RESET pin. 3. RST pin description is now RESET pin description. 4. Figure 6 ICC vs. Frequency has been corrected to show test conditions. 5. ICC Max spec has been corrected. 6. A.C. Characteristic table 1/TCLCL spec has been changed to have a Max frequency of 16 MHz. The following are key differences between the -005 and the -004 version of the datasheet: 1. ‘‘NC’’ pin labels changed to ‘‘Reserved’’ in Figure 3. 2. Capacitor value for ceramic resonators deleted in Figure 4. The following are the key differences between the -003 version of the 8XC51FA datasheet and the -004 version of the 80C51FA/83C51FA datasheet: 1. Removed references to EPROM from the 8XC51FA datasheet. 2. Revised Figure 4, ‘‘Oscillator Connections’’. The following are the key differences between the -002 and the -003 version of this datasheet: 1. Dropped word ‘‘maximum’’ from IOL in the Absolute Maximum Rating table. 2. Dropped EA from ILI specification of the DC table. 3. Corrected TQVWH specification (from TTCLCL b 70 to TCLCL b 150). 4. Added note on external clock capacitance loading. 5. Changed the title to 80C51FA/83C51FA Event-Control CHMOS Single-Chip 8-Bit Microcontroller. 6. Added pin count to Figure 1. 7. Changed ILI to g 10 mA. 8. Added ICC Power Down Mode 150 nA. 13