Toshiba TLCS-900/H1 Series Manual page 127

3.7 8-Bit Timers (TMRA)
The TMP92CH21 features 4 built-in 8-bit timers (TMRA0-TMRA3).
These timers are paired into two modules: TMRA01 and TMRA23. Each module consists of two
channels and can operate in any of the following four operating modes.
•
8-bit interval timer mode
• 16-bit interval timer mode
• 8-bit programmable square wave pulse generation output mode
(PPG: Variable duty cycle with variable period)
•
8-bit pulse width modulation output mode
(PWM: Variable duty cycle with constant period)
Figure 3.7.1 and Figure 3.7.2 show block diagrams for TMRA01 and TMRA23.
Each channel consists of an 8-bit up counter, an 8-bit comparator and an 8-bit timer register.
In addition, a timer flip-flop and a prescaler are provided for each pair of channels.
The operation mode and timer flip-flops are controlled by a five-byte SFR (special function
register).
Each of the two modules (TMRA01 and TMRA23) can be operated independently. All modules
operate in the same manner; hence only the operation of TMRA01 is explained here.
The contents of this chapter are as follows.
3.7.1 Block Diagrams
3.7.2 Operation of Each Circuit
3.7.3 SFR
3.7.4 Operation in Each Mode
(1) 8-bit timer mode
(2) 16-bit timer mode
(3) 8-bit PPG (programmable pulse generation) output mode
(4) 8-bit PWM (pulse width modulation) output mode
(5) Mode settings
External
pin
SFR
(Address)
Table 3.7.1 Registers and Pins for Each Module
Module
Input pin for external clock
Output pin for timer flip-flop
Timer run register
Timer register
Timer mode register
Timer flip-flop control register
92CH21-125
TMRA01 TMRA23
No
TA1OUT
(Shared with PC0) (Shared with PC1)
TA01RUN (1100H) TA23RUN (1108H)
TA0REG (1102H) TA2REG (110AH)
TA1REG (1103H) TA3REG (110BH)
TA01MOD (1104H) TA23MOD (110CH)
TA1FFCR (1105H) TA3FFCR (110DH)
TMP92CH21
No
TA3OUT
2009-06-19