R8C2C datasheet(115/615 Pages) RENESAS

115 / 615 page

R8C/2C Group, R8C/2D Group

9. Bus

Rev.2.00

Dec 05, 2007

Page 94 of 585

REJ09B0339-0200

Bus

The bus cycles differ when accessing ROM/RAM, and when accessing SFR.

Table 9.1 lists Bus Cycles by Access Space of the R8C/2C Group and Table 9.2 lists Bus Cycles by Access Space of

the R8C/2D Group.

ROM/RAM and SFR are connected to the CPU by an 8-bit bus. When accessing in word (16-bit) units, these areas are

accessed twice in 8-bit units.

Table 9.3 lists Access Units and Bus Operations and Table 9.4 lists Access Units and Bus Operations of SFR (address

0200h to 02FFh).

Table 9.3

Access Units and Bus Operations

Table 9.1

Bus Cycles by Access Space of the R8C/2C Group

Access Area

Bus Cycle

SFR (address 0000h to 01FFh)

2 cycles of CPU clock

SFR (address 0200h to 02FFh)

3 cycles of CPU clock

ROM/RAM

1 cycle of CPU clock

Table 9.2

Bus Cycles by Access Space of the R8C/2D Group

Access Area

Bus Cycle

SFR (address 0000h to 01FFh)/Data flash 2 cycles of CPU clock

SFR (address 0200h to 02FFh)

3 cycles of CPU clock

Program ROM/RAM

1 cycle of CPU clock

Area

SFR (address 0000h to 01FFh), data flash

Even address

Byte access

ROM (program ROM), RAM

Odd address

Byte access

Even address

Word access

Odd address

Word access

CPU clock

Data

Even

Address

CPU

clock

Data

Address

CPU

clock

Data

Address

CPU

clock

Data

Address

CPU

clock

Data

Address

CPU

clock

Data

Address

CPU

clock

Data

Address

CPU

clock

Data

Address

Data

Odd

Data

Even

Even + 1

Data

Odd

Odd + 1

Data

Even

Even + 1

Data

Odd

Odd + 1

Data

R8C2C Datasheet(PDF) 115 Page - Renesas Technology Corp

R8C2C Datasheet(HTML) 115 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

Datasheet Download

Link URL