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.

Extended Automotive Temperature Range (b4⁰C to a125^oC Ambient)
High Performance CHMOS Process
Three 16-Bit Timer/Counters
  Timer 2 is an Up/Down Timer/Counter
Programmable Counter Arrawith:
  High Speed Output,
  Compare/Capture,
  Pulse Width Modulator,
  Watchdog Timer Capabilities
8K On-Chip ROM
256 Bytes of On-Chip Data RAM
Boolean Processor
32 Programmable I/O Lines
7 Interrupt Sources
Programmable Serial Channel with:
  Framing Error Detection
  Automatic Address Recognition
TTL and CMOS Compatible Logic Levels
64K External Program MemorSpace
64K External Data MemorSpace
MCSÉ 51 Microcontroller Fully Compatible Instruction Set
Power Saving Idle and Power Down Modes
ONCE (On-Circuit Emulation) Mode
Available in PLCC and PDIP Packages (See Packaging Specification, Order Ý231369)
Available in 12 MHz and 16 MHz Versions