The 68HC11 is a powerful 8-bit data, 16-bit address microcontroller from
Motorola with an instruction set that is similar to the older 68xx (6801,
6805, 6809) parts. Depending on the variety, the 68HC11 has built-in
EEPROM/OTPROM, RAM, digital I/O, timers, A/D converter, PWM generator, and
synchronous and asynchronous communications channels (RS232 and SPI). Typical
current draw is less than 10mA.
The M68HC11 is optimized for low power consumption and high-performance operation
at bus frequencies up to 4 MHz. The CPU has two 8 bit accumulators (A &
B) that can be concatenated to provide a 16 bit double accumulator (D). Two
16 bit index registers are present (X & Y) to provide indexing to anywhere
in the memory map. Having the two index registers means the 68HC11 is very
good for processing data. Although an eight bit processor, the 68HC11 has
some 16 bit instructions (add, subtract, 16 * 16 divide, 8 * 8 multiply,
shift, and rotates). A 16 bit stack pointer is also present, and instructions
are provided for stack manipulation. Typically multiplexed address and data
bus.
Other features include:
