
123
μ
PD75238
(4) Display mode register (DSPM)
The display mode register (DSPM) is a 4-bit register for enable/disable setting for the display operation
and for specifying the number of display segments. Fig. 4-70 shows the format of the register.
The display mode register is set with a 4-bit memory manipulation instruction.
Before a standby mode (STOP mode or HALT mode) can be set or the subsystem clock (f
XT
) can be used
for operation, display must be disabled by setting DSPM.3 to 0.
A RESET input clears all bits to 0.
Fig. 4-70 Display Mode Register Format
(5) Digit select register (DIGS)
The digit select register (DIGS) is a 4-bit register that specifies the number of display digits. Fig. 4-71 shows
the format of the register.
DIGS is set with a 4-bit memory manipulation instruction. This register enables the number of display
digits to be selected from 9 to 16 digits. No other values can be selected.
A RESET input initializes the register to 1000B so that 9-digit display is selected.
Fig. 4-71 Digit Select Register Format
3
2
1
0
DSPM3
DSPM2
DSPM1
DSPM0
Address
F88H
Symbol
DSPM
Bit for specifying the number of display segments
DSPM2
0
0
0
0
1
1
1
1
DSPM1
0
0
1
1
0
0
1
1
DSPM0
0
1
0
1
0
1
0
1
Number of display segments
9 segments (+ 8 segments)
10 segments (+ 8 segments)
11 segments (+ 8 segments)
12 segments (+ 8 segments)
13 segments (+ 8 segments)
14 segments (+ 8 segments)
15 segments (+ 8 segments)
16 segments (+ 8 segments)
Remark
Segments in parentheses are added when pins S16 to S23 are specified as dynamic mode
in STATB.
Display operation enable/disable bit
DSPM3
0
1
Display disabled
Display enabled
3
2
1
0
DIGS3
DIGS2
DIGS1
DIGS0
Address
F8AH
Symbol
DIGS
Caution Do not set a value from 0 to 7 for N.
DIGS0-3 set value
N (= 8 to 15)
Number of display digits
N + 1