M16CSLASH62M datasheet(52/615 Pages) RENESAS

52 / 615 page

Mitsubishi microcomputers

M16C / 62A Group

SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Bus Control

1-33

Table 1.9.6. Microcomputer status in hold state

Item

Status

Oscillation

___

_____

_______

R/W signal, address bus, data bus, CS, BHE

Floating

Programmable I/O ports

P0, P1, P2, P3, P4, P5

Floating

P6, P7, P8, P9, P10

Maintains status when hold signal is received

__________

HLDA

Output “L”

Internal peripheral circuits

ON (but watchdog timer stops)

ALE signal

Undefined

__________

HOLD > DMAC > CPU

(6) Hold signal

The hold signal is used to transfer the bus privileges from the CPU to the external circuits. Inputting “L” to

__________

the HOLD pin places the microcomputer in the hold state at the end of the current bus access. This status

__________

is maintained and “L” is output from the HLDA pin as long as “L” is input to the HOLD pin. Table 1.9.6

shows the microcomputer status in the hold state.

__________

Bus-using priorities are given to HOLD, DMAC, and CPU in order of decreasing precedence.

Figure 1.9.5. Bus-using priorities

(7) External bus status when the internal area is accessed

Table 1.9.7 shows the external bus status when the internal area is accessed.

Table 1.9.7. External bus status when the internal area is accessed

Item

SFR accessed

Internal ROM/RAM accessed

Address bus

Address output

Maintain status before accessed

address of external area

Data bus

When read

Floating

When write

Output data

Undefined

RD, WR, WRL, WRH

RD, WR, WRL, WRH output

Output “H”

BHE

BHE output

Maintain status before accessed

status of external area

Output “H”

ALE

Output “L”

M16C/62M Datasheet(PDF) 52 Page - Renesas Technology Corp

M16C/62M Datasheet(HTML) 52 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