M16C29 Datasheet, PDF (143/499 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/Tiny SERIES

M16C/29 Group
12. Timer B
12.2.1 Timer Mode
In timer mode, the timer counts a count source generated internally (see Table 12.6). Figure 12.18
shows TBiMR register in timer mode.
Table 12.6 Specifications in Timer Mode
Item
Specification
Count source
f1, f2, f8, f32, fC32
Count operation
• Decrement
• When the timer underflows, it reloads the reload register contents and
continues counting
Divide ratio
Count start condition
1/(n+1) n: set value of TBi register (i= 0 to 2) 000016 to FFFF16
Set TBiS bit⁽¹⁾ to 1 (start counting)
Count stop condition
Set TBiS bit to 0 (stop counting)
Interrupt request generation timing Timer underflow
TBiIN pin function
I/O port
Read from timer
Count value can be read by reading TBi register
Write to timer
• When not counting and until the 1st count source is input after counting start
Value written to TBi register is written to both reload register and counter
• When counting (after 1st count source input)
Value written to TBi register is written to only reload register
(Transferred to counter when reloaded next)
NOTE:
1. Bits TB0S to TB2S are assigned to the bit 7 to bit 5 in the TABSR register.
Timer Bi Mode Register (i= 0 to 2)
b7 b6 b5 b4 b3 b2 b1 b0
00
Symbol
TB0MR to TB2MR
Address
039B16 to 039D16
After Reset
00XX00002
Bit Symbol
TMOD0
TMOD1
MR0
MR1
MR2
MR3
TCK0
TCK1
Bit Name
Function
Operation mode select bit ^{b1 b0}
0 0: Timer mode or A/D trigger mode
No effect in timer mode
Can be set to 0 or 1
TB0MR register
Set to 0 in timer mode
TB1MR, TB2MR registers
Nothing is assigned. If necessary, set to 0. When read, its
content is undefined
When write in timer mode, set to 0. When read in timer mode, its
content is undefined
Count source select bit
b7 b6
0 0: f1 or f2
0 1: f8
1 0: f32
1 1: fC32
RW
RW
RW
RW
RW
RW
RO
RW
RW
Figure 12.18 TBiMR Register in Timer Mode
Rev. 1.12 Mar.30, 2007 ^{page 119} of 458
REJ09B0101-0112