HD6433637SW datasheet(33/418 Pages) RENESAS

33 / 418 page

2.3.2

Memory Data Formats

Figure 2.4 indicates the data formats in memory. For access by the H8/300L CPU, word data

stored in memory must always begin at an even address. In word access the least significant bit of

the address is regarded as 0. If an odd address is specified, the access is performed at the preceding

even address. This rule affects the MOV.W instruction, and also applies to instruction fetching.

Data Format

76543210

Address

Data Type

Address n

MSB

LSB

MSB

LSB

Upper 8 bits

Lower 8 bits

MSB

LSB

CCR

CCR*

MSB

LSB

MSB

LSB

Address n

Even address

Odd address

Even address

Odd address

Even address

Odd address

1-bit data

Byte data

Word data

Byte data (CCR) on stack

Word data on stack

CCR: Condition code register

Note:

Ignored on return

Figure 2.4 Memory Data Formats

When the stack is accessed using R7 as an address register, word access should always be

performed. When the CCR is pushed on the stack, two identical copies of the CCR are pushed to

make a complete word. When they are restored, the lower byte is ignored.

HD6433637SW Scheda tecnica(PDF) 33 Page - Renesas Technology Corp

HD6433637SW Scheda tecnica(HTML) 33 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Scheda tecnica Scarica

Link URL