Page 391 - Introduction to Microcontrollers Architecture, Programming, and Interfacing of The Motorola 68HC12

368 Chapter 12 Other Microcontrollers

Table 12.7. Instructions for the 500 Series

The RISC architecture uses three-register-address instructions for all arithmetic,
logical, and edit instructions. There are also immediate operand arithmetic instructions,
but no arithmetic instructions that access memory. For instance, the add instruction add
r3 , r4 , r5 puts the sum in r3 of r4 plus r.5. Letters appended to the mnemonic enable
other results of addition to be recorded or used. If a letter "c" is appended, the carry bit in
the integer exception register is loaded with the carry out of the addition; if a letter "o" is