68
PRELIMINARY
Notice: This is not a final specification.
Some parametric limits are subject to change.
MITSUBISHI MICROCOMPUTERS
M37754M8C-XXXGP, M37754M8C-XXXHP
M37754S4CGP, M37754S4CHP
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Particular function select register 0
External clock input select bit
(Notes 1, 2)
0 : Actuated oscillation circuit; connecting resonator
1 : Stopped oscillation circuit; inputting externaly genarated clock
Standby state select bit 0
(Notes 1, 3)
; in execution of WIT or STP instruction in memory expansion
or microprocessor mode
0 : External bus for P0 to P3, P10, P11
1 : Port Input/Output for P0 to P3, P10, P11
Standby state select bit 1
(Notes 1, 4)
; in execution of WIT or STP instruction
0 :
“H” or “L” output for pins E/RD, WR
1 :
“H” output for pins E/RD, WR
Memory allocation select bit
(Note 2)
0 : ROM 60 Kbytes, RAM 2048 Bytes
(ROM : 001000
16
to 00FFFF
16
, RAM : 000080
16
to 00087F
16
)
1 : ROM 56 Kbytes, RAM 2048 Bytes
(ROM:002000
16
to 00FFFF
16
, RAM:000080
16
to 00087F
16
)
This bit must be fixed to “0.”
Address
6C
16
Notes 1 :
After the expansion function select bit (bit 5 of particular function select register 1; Figure 62) is “1”,
bits 1, 5 and 6 can be written and changed.
2 :
To set bits 1 and 2, continuous-twice-write operations to address 6C
16
are required.
3 :
When BYTE = “H” (8-bit external bus width), P11 becomes an input/output port independent of bit 5’s contents.
4 :
When the signal output disable select bit = “1” and bit 5 = “1”, the E/RD pin outputs “L” independent of bit 6’s contents
in execution of WIT or STP instruction.
Fig. 83 Particular function select register 0 bit configulation
7
6
5
4
3
2
1
0
0
STP rerurn select bit
0 : Wachdog timer is used when returning from Stop mode.
1 : Wachdog timer is not used when returning from Stop mode ; the maicrocomputer returns
at once.