7751 Datasheet, PDF (90/540 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER

TIMER A
5.3 Timer mode
5.3 Timer mode
In this mode, the timer counts an internally generated count source. (Refer to Table 5.3.1.) Figure 5.3.1
shows the structures of the timer Ai mode register and timer Ai register in the timer mode.
Table 5.3.1 Specifications of timer mode
Item
Count source
Count operation
Specifications
f2/f4, f16/f32, f64/f128, or f512/f1024
• Down-count
• When the counter underflows, reload register’s contents are reloaded
Count start condition
and counting continues.
When count start bit is set to “1.”
Count stop condition
When count start bit is cleared to “0.”
Interrupt request occurrence timing When the counter underflows.
TAiIN pin function
TAiOUT pin function
Read from timer Ai register
Write to timer Ai register
Programmable I/O port or gate input
Programmable I/O port or pulse output
Counter value can be read out.
q While counting is stopped
When a value is written to timer Ai register, it is written to both
reload register and counter.
q While counting is in progress
When a value is written to timer Ai register, it is written to only
reload register. (Transferred to counter at next reload timing.)
7751 Group User’s Manual
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