M30622SAFP MITSUBISHI [Mitsubishi Electric Semiconductor], M30622SAFP Datasheet - Page 31

• Manufacturer Part Number: M30622SAFP
• Description: SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

Bus Control
Table 1.9.6. Microcomputer status in hold state
Figure 1.9.4. Bus-using priorities
Table 1.9.7. External bus status when the internal area is accessed
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Oscillation
R/W signal, address bus, data bus, CS, BHE
Programmable I/O ports
HLDA
Internal peripheral circuits
ALE signal
(6) Hold signal
(7) External bus status when the internal area is accessed
Item
Address bus
Data bus
RD, WR, WRL, WRH
BHE
CS
ALE
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.
Table 1.9.7 shows the external bus status when the internal area is accessed.
___
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When read
When write
Item
SFR accessed
Address output
Floating
Output data
RD, WR, WRL, WRH output
BHE output
Output “H”
Output “L”
P6, P7, P8, P9, P10
P0, P1, P2, P3, P4, P5
__________
_____
__________
HOLD > DMAC > CPU
_______
__________
ON
Floating
Floating
Maintains status when hold signal is received
Output “L”
ON (but watchdog timer stops)
Undefined
Internal ROM/RAM accessed
Maintain status before accessed
address of external area
Floating
Undefined
Output “H”
Maintain status before accessed
status of external area
Output “H”
Output “L”
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Status
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M16C / 62A Group
Mitsubishi microcomputers
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