Arrangement Of 16-Bit Data In Memory Space; Fig. 2.2 Arrangement Of 16 Bit Data In Memory Space; Fig. 2.3 Arrangement Of 16 Bit Data During Execution Of Instruction - Fujitsu F2MC-8L Family series Hardware Manual

CPU
Before execution
1234
A
H

Fig. 2.2 Arrangement of 16 bit Data in Memory Space

Fig. 2.3 Arrangement of 16 bit Data during Execution of Instruction

HARDWARE CONFIGURATION

2.1.2 Arrangement of 16-bit Data in Memory Space

When the MB89950 series of microcontrollers handle 16-bit data, the data
written at the lower address is treated as the upper 8-bit data and that written
at the next address is treated as the lower 8-bit data as shown in Fig. 2.2.
Memory
MOVW ABCD
ABCF
H
ABCE
H
ABCD
H
ABCC
H
This is the same when 16 bits are specified by the operand during execution
of an instruction. Bits closer to the OP code are treated as the upper byte
and those next to it are treated as the lower byte. This is also the same
when the memory address or 16-bit immediate data is specified by the
operand.
[Example]
; Extended address
MOV A, 5678
H
; 16-bit immediate data
MOV A, #1234
H
Assemble
XXXX XX XX
H
; Extended address
XXXX 60 56 78
H
; 16-bit immediate data
XXXX E4 12 34
H
XXXX XX
H
Data saved in the stack by an interrupt is also treated in the same manner.
2– 5
After execution
, A
H
1234
A
H
Memory
ABCF
H
34
ABCE
H
H
12
ABCD
H
H
ABCC
H