41
MB90F243H
s INSTRUCTION SET (412 INSTRUCTIONS)
Table 1
Explanation of Items in Table of Instructions
Item
Explanation
Mnemonic
Upper-case letters and symbols: Represented as they appear in assembler
Lower-case letters: Replaced when described in assembler.
Numbers after lower-case letters: Indicate the bit width within the instruction.
#
Indicates the number of bytes.
~
Indicates the number of cycles.
See Table 4 for details about meanings of letters in items.
B
Indicates the correction value for calculating the number of actual cycles during
execution of instruction.
The number of actual cycles during execution of instruction is summed with the value in
the “cycles” column.
Operation
Indicates operation of instruction.
LH
Indicates special operations involving the bits 15 through 08 of the accumulator.
Z: Transfers “0”.
X: Extends before transferring.
—: Transfers nothing.
AH
Indicates special operations involving the high-order 16 bits in the accumulator.
*: Transfers from AL to AH.
—: No transfer.
Z: Transfers 00H to AH.
X: Transfers 00H or FFH to AH by extending AL.
I
Indicates the status of each of the following flags: I (interrupt enable), S (stack), T (sticky
bit), N (negative), Z (zero), V (overflow), and C (carry).
*: Changes due to execution of instruction.
—: No change.
S: Set by execution of instruction.
R: Reset by execution of instruction.
S
T
N
Z
V
C
RMW
Indicates whether the instruction is a read-modify-write instruction (a single instruction
that reads data from memory, etc., processes the data, and then writes the result to
memory.).
*: Instruction is a read-modify-write instruction
—: Instruction is not a read-modify-write instruction
Note: Cannot be used for addresses that have different meanings depending on
whether they are read or written.