1Timer Mode - Renesas M16C FAMILY Hardware Manual

Under development
Preliminary specification
Specifications in this manual are tentative and subject to change.
R8C/11 Group
12.3.1 Timer Mode
In this mode, the timer counts an internally generated count source or Timer Y underflow (see "Table
12.9 Timer Mode Specifications"). The TZSC register is unused in timer mode. Figure 12.22 shows
the TYZMR register and PUM register in timer mode.
Table 12.9 Timer Mode Specifications
Item
Count source
Count operation
Divide ratio
Count start condition
Count stop condition
Interrupt request
generation timing
TZ pin function
OUT
INT0 pin function
Read from timer
1
Write to timer
Notes:
1. The IR bit in the TZIC register is set to "1" (interrupt requested) if you write to the TZPR or PREZ register while both
of the following conditions are met.
<Conditions>
• TZWC bit in TYZMR register is set to "0" (write to reload register and counter simultaneously)
• TZS bit in TYZMR register is set to "1" (count start)
To write to the TZPR or PREZ register in the above state, disable interrupts before the writing.
Rev.0.91 2003 Sep 08
f , f , f , Timer Y underflow
1 2 8
• Down-count
• When the timer underflows, it reloads the reload register contents before continuing
counting (When the Timer Z underflows, the contents of the Timer Z primary reload
register is reloaded.)
fi/(n+1)(m+1) n: set value in PREZ register, m: set value in TZPR register
Write "1" (count start) to TZS bit in TYZMR register
Write "0" (count stop) to TZS bit in TYZMR register
• When Timer Z underflows [Timer Z interrupt]
• Rising, falling, or both edges of INT0 pin input [INT0 interrupt]
Programmable I/O port
Programmable I/O port, or external interrupt input pin
Count value can be read out by reading TZPR register.
Same applies to PREZ register.
Value written to TZPR register is written to both reload register and counter or written to
reload register only. Selected by program.
Same applies to PREZ register.
page 91 of 184
Specification
12.3 Timer (Timer Z)