Renesas 6NM User Manual

Rev.1.10    Jul 01, 2005    page 95 of 318
REJ09B0124-0110

M16C/6N Group (M16C/6NK, M16C/6NM)

12. Timers

This document is under development and its contents are subject to change.

Timer Ai Mode Register (i = 0 to 4)

TA0MR to TA4MR

Bit Name

Function

Bit Symbol

RW

b7

b6

b5

b4

b3

b2

b1

b0

0 0 : Timer mode
0 1 : Event counter mode
1 0 : One-shot timer mode
1 1 : Pulse width modulation mode

 

 

b1 b0 

Count Source Select Bit

RW

RW

RW

RW

RW

RW

RW

RW

Function varies with each 
operation mode

Symbol

Function varies with each operation mode

Operation Mode Select Bit

TCK1

MR3

MR2

MR1

TMOD1

MR0

TMOD0 

TCK0

0396h to 039Ah

00h

Address

After Reset

Symbol

Address

After Reset 

TA0

0387h to 0386h
0389h to 0388h
038Bh to 038Ah
038Dh to 038Ch
038Fh to 038Eh

Indeterminate

 

TA1

Indeterminate

 

TA2

Indeterminate

 

TA3

Indeterminate

 

TA4

b7

b0 b7

b0

(b15)

(b8)

Timer Ai Register (i = 0 to 4) 

(1)

RW

Divide the count source by n + 1 where n = 
set value

Function

Setting Range

Divide the count source by n where n = set 
value and cause the timer to stop

Modify the pulse width as follows:
PWM period: (2

16

 — 1) / fj

High level PWM pulse width: n / fj 
where n = set value, fj = count source 
frequency

 

NOTES:

1. The register must be accessed in 16-bit unit.
2. The timer counts pulses from an external device or overflows or underflows in other timers.
3. If the TAi register is set to "0000h", the counter does not work and timer Ai interrupt requests are

not generated either. Furthermore, if "pulse output" is selected, no pulses are output from the
TAiOUT pin.

4. Use the MOV instruction to write to the TAi register.
5. If the TAi register is set to "0000h", the pulse width modulator does not work, the output level on

the TAiOUT pin remains low, and timer Ai interrupt requests are not generated either. 
The same applies when the 8 high-order bits in the TAi register are set to "00h" while operating as
an 8-bit pulse width modulator.

RW

RW

WO

WO

WO

Timer 
Mode

Event 
Counter 
Mode

One-shot  
Timer Mode

Pulse Width 
Modulation 
Mode

(16-bit PWM )

Pulse Width 
Modulation  
Mode

(8-bit PWM )

0000h to FFFFh

0000h to FFFFh

00h to FEh
(High-order address)
00h to FFh
(Low-order address)

0000h to FFFFh

 (3) (4)

0000h to FFFEh

 (4) (5)

 

Mode

Modify the pulse width as follows:
PWM period: ( 2

8

 — 1) 

✕ (m + 1)/ fj

High level PWM pulse width: (m + 1)n / fj  
where n = high-order address set value,  
m = low-order address set value, fj = 
count source frequency

Divide the count source by FFFFh — n + 1
where n = set value when counting up or 
by n + 1 when counting down 

(2)

Indeterminate