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CHAPTER 8 8-BIT TIMER/EVENT COUNTERS 50, 51, 52
User
’
s Manual U14701EJ3V0UD
8.3 8-Bit Timer/Event Counters 50, 51, and 52 Configurations
8-bit timer/event counters 50, 51, and 52 consist of the following hardware.
Table 8-1. 8-Bit Timer/Event Counters 50, 51, and 52 Configuration
Item
Configuration
Timer register
8-bit timer counter 5n (TM5n)
Register
8-bit timer compare register 5n (CR5n)
Timer output
3 (TO5n)
Control registers
Timer clock select register 5n (TCL5n)
8-bit timer mode control register 5n (TMC5n)
Port mode registers 3, 7 (PM3, PM7)
Note
Note
See
Figure 4-9 P33, P34 Block Diagram
,
Figure 4-15 P70, P72
Block Diagram
, and
Figure 4-16 P71, P73 Block Diagram.
Remark
n = 0 to 2
(1) 8-bit timer counter 5n (TM5n: n = 0 to 2)
TM5n is an 8-bit read-only register which counts the count pulses.
A counter is incremented in synchronization with the rising edge of a count clock.
When count value is read during operation, count clock input is temporary stopped, and then the count value
is read. In the following situations, count value is set to 00H.
<1>
RESET input
<2>
When TCE5n is cleared
<3>
When TM5n and CR5n match in clear & start mode if this mode was entered upon match of TM5n and CR5n
values.
Remark
n = 0 to 2
(2) 8-bit timer compare register 5n (CR5n: n = 0 to 2)
The value set in CR5n is constantly compared with the 8-bit timer counter 5n (TM5n) count value, and an interrupt
request (INTTM5n) is generated if they match (except PWM mode).
It is possible to rewrite the value of CR5n within 00H to FFH during count operation.
Remark
n = 0 to 2