HD404818 Datasheet, PDF (55/100 Pages) Hitachi Semiconductor – 16-digit LCD driver

HD404818 Series
5. The division ratio must not be modified during time base mode operation, otherwise an overflow
cycle error will occur.
Timer Mode Register C (TMC: $00D): Timer mode register C is a 4-bit write-only register which selects
the auto-reload function, input clock source, and prescaler divide ratio, as table 23 shows. Timer mode
register C is initialized to $0 at MCU reset.
The contents of timer mode register C will change in the second instruction cycle after a write instruction to
TMC. Therefore, it is required to initialize timer C after the contents of timer mode register C have been
changed completely.
Timer B (TCBL: $00A, TCBU: $00B, TLRL: $00A, TLRU: $00B): Timer B consists of an 8-bit write-
only timer load register, and an 8-bit read-only timer counter. Each of them has low-order digits (TCBL:
$00A, TLRL: $00A) and high-order digits (TCBU: $00B, TLRU: $00B). (Refer to figure 26.)
Timer counter B can be initialized by writing data into timer load register B. In this case, write the low-
order digits first, and then the high-order digits. The timer counter is initialized when the high-order digit
is written. The timer load register is initialized to $00 by MCU reset.
The counter value of timer B can be obtained by reading timer counter B. In this case, read the high-order
digits first, and then the low-order digits. The count value of the low-order digit is obtained when the high-
order digit is read.
Timer C (TCCL: $00E, TCCU: $00F, TCRL: $00E, TCRU: $00F): Timer C consists of the 8-bit write-
only timer load register and the 8-bit read-only timer counter. These individually consist of low-order digits
(TCCL: $00E, TCRL: $00E) and high-order digits (TCCU: $00F, TCRU: $00F). The operation mode of
timer C is the same as that of timer B.
Table 22 Timer Mode Register B
TMB3
0
1
Auto-Reload Function
No
Yes
TMB2
0
0
0
0
1
1
1
1
TMB1
0
0
1
1
0
0
1
1
TMB0
0
1
0
1
0
1
0
1
Prescaler Divide Ratio, Clock Input Source
÷ 2048
÷ 512
÷ 128
÷ 32
÷8
÷4
÷2
INT₁ (external event input)
53