Datasheet
Table Of Contents
- FEATURES
- DETAILED DESCRIPTION
- ORDERING INFORMATION
- Figure 1. Block Diagram
- PIN DESCRIPTION
- 80C32 COMPATIBILITY
- Figure 2. Comparative Timing of the DS80C320/DS80C323 and 80C32
- HIGH-SPEED OPERATION
- INSTRUCTION SET SUMMARY
- Table 1. Instruction Set Summary
- SPEED ADVANTAGE SUMMARY
- MEMORY ACCESS
- Figure 3. Typical Memory Connection
- STRETCH MEMORY CYCLE
- Table 2. Data Memory Cycle Stretch Values
- DUAL DATA POINTER
- 64-Byte Block Move without Dual Data Pointer
- 64-Byte Block Move with Dual Data Pointer
- PERIPHERAL OVERVIEW
- SERIAL PORTS
- TIMER-RATE CONTROL
- POWER-FAIL RESET
- POWER-FAIL INTERRUPT
- WATCHDOG TIMER
- Table 3. Watchdog Timeout Values
- INTERRUPTS
- Table 4. Interrupt Priority
- POWER MANAGEMENT
- IDLE MODE ENHANCEMENTS
- STOP MODE ENHANCEMENTS
- Figure 4. Ring Oscillator Startup
- TIMED ACCESS PROTECTION
- SPECIAL-FUNCTION REGISTERS
- Table 5. Special-Function Register Locations
- ELECTRICAL SPECIFICATIONS
- ABSOLUTE MAXIMUM RATINGS
- DC ELECTRICAL CHARACTERISTICS—DS80C320
- NOTES FOR DS80C320 DC ELECTRICAL CHARACTERISTICS
- TYPICAL ICC vs. FREQUENCY
- AC CHARACTERISTICS—DS80C320
- NOTES FOR DS80C320 AC ELECTRICAL CHARACTERISTICS
- MOVX CHARACTERISTICS—DS80C320
- DC ELECTRICAL CHARACTERISTICS—DS80C323
- NOTES FOR DS80C323 DC ELECTRICAL CHARACTERISTICS
- NOTES FOR DS80C323 DC ELECTRICAL CHARACTERISTICS (continued)
- AC ELECTRICAL CHARACTERISTICS—DS80C323
- NOTES FOR DS80C323 AC ELECTRICAL CHARACTERISTICS
- MOVX CHARACTERISTICS—DS80C323
- EXTERNAL CLOCK CHARACTERISTICS
- SERIAL PORT MODE 0 TIMING CHARACTERISTICS
- EXPLANATION OF AC SYMBOLS
- POWER-CYCLE TIMING CHARACTERISTICS
- NOTES FOR POWER CYCLE TIMING CHARACTERISTICS
- PROGRAM MEMORY READ CYCLE
- DATA MEMORY READ CYCLE
- DATA MEMORY WRITE CYCLE
- DATA MEMORY WRITE WITH STRETCH = 1
- DATA MEMORY WRITE WITH STRETCH = 2
- EXTERNAL CLOCK DRIVE
- SERIAL PORT MODE 0 TIMING
- POWER-CYCLE TIMING
- DATA SHEET REVISION SUMMARY
DS80C320/DS80C323 High-Speed/Low-Power Microcontrollers
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a 25MHz crystal frequency. Note that once the counter chain has reached a conclusion, the optional
interrupt is generated. Regardless of whether the user enables this interrupt, there are then 512 clocks left
until a reset occurs. There are 5 control bits in special function registers that affect the Watchdog Timer
and two status flags that report to the user. The Reset Watchdog Timer bit (WDCON.0) should be
asserted prior to modifying the Watchdog Timer Mode Select bits (WD1, WD0) to avoid corruption of
the watchdog count.
WDIF (WDCON.3) is the interrupt flag that is set when there are 512 clocks remaining until a reset
occurs. WTRF (WDCON.2) is the flag that is set when a Watchdog reset has occurred. This allows the
application software to determine the source of a reset.
Setting the EWT (WDCON.1) bit enables the Watchdog Timer. The bit is protected by timed access.
Setting the RWT (WDCON.0) bit restarts the Watchdog Timer for another full interval. Application
software must set this bit prior to the timeout. As mentioned previously, WD1 and 0 (CKCON .7 and 6)
select the timeout. Finally, the Watchdog Interrupt is enabled using EWDI (EIE.4).
INTERRUPTS
The DS80C320/DS80C323 provide 13 sources of interrupt with three priority levels. The Power-fail
Interrupt (PFI), if enabled, always has the highest priority. There are two remaining user-selectable
priorities: high and low. If two interrupts that have the same priority occur simultaneously, the natural
precedence given in Table 4 determines which is acted upon. Except for the PFI, all interrupts that are
new to the 8051 family have a lower natural priority than the originals.
Table 4. Interrupt Priority
NAME FUNCTION VECTOR
NATURAL
PRIORITY
OLD/NEW
PFI Power-Fail Interrupt 33h j 1 New
INT0
External Interrupt 0 03h 2 Old
TF0 Timer 0 0Bh 3 Old
INT1
External Interrupt 1 13h 4 Old
TF1 Timer 1 1Bh 5 Old
SCON0 TI0 or RI0 from Serial Port 0 23h 6 Old
TF2 Timer 2 2Bh 7 Old
SCON1 TI1 or RI1 from Serial Port 1 3Bh 8 New
INT2 External Interrupt 2 43h 9 New
INT3
External Interrupt 3 4Bh 10 New
INT4 External Interrupt 4 53h 11 New
INT5
External Interrupt 5 5Bh 12 New
WDTI Watchdog Timeout Interrupt 63h 13 New