HD6435348R Hitachi Semiconductor, HD6435348R Datasheet - Page 63

• Manufacturer Part Number: HD6435348R
• Description: Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

Table 3-5 Data Formats in Memory
Data Type
1-Bit (in byte
operand data)
1-Bit (in word
operand data)
Byte
Word
When the stack is accessed in exception processing (to save or restore the program counter, code
page register, or status register), word access is always performed, regardless of the actual data
size. Similarly, when the stack is accessed by an instruction using the pre-decrement or post-
increment register indirect addressing mode specifying R7 (@–R7 or @R7+), which is the stack
pointer, word access is performed regardless of the operand size specified in the instruction. An
address error will therefore occur if the stack pointer indicates an odd address. Programs should
be coded so that the stack pointer always indicates an even address.
Table 3-6 shows the data formats on the stack.
Data Format
Even address
Address n
Odd address
Address n
Even address
Odd address
7
43
15
MSB
MSB
7
7
14
6
6
13
5
5
Upper 8 bits
Lower 8 bits
12
4
4
11
3
3
10
2
2
1
9
1
LSB
LSB
0
8
0
0