Format Of 8-Bit Timer Mode Control Register 30 - NEC PD789860 User Manual

(1) 8-bit timer mode control register 30 (TMC30)
TMC30 is the register that controls the setting of the timer 30 count clock and the setting of the operating
mode.
This register is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input clears this register to 00H.
Figure 9-4. Format of 8-Bit Timer Mode Control Register 30
Symbol <7> 6
TMC30 TCE30 0
TCE30
0 Clears TM30 count value and halt operation
1 Starts count operation
TCL302 TCL301
0 0
0 0
0 1
0 1
Other than above
TMD301 TMD300
0 0
0 1
0 0
0 0
Other than above
Notes 1. In cascade connection mode, since count operations are controlled by TCE40 (bit 7 of TMC40),
TCE30 is ignored even if it is set.
2. The selection of operating mode is made by combining the two registers TMC30 and TMC40.
Cautions 1. Be sure to clear bits 0 and 6 to 0.
2. In cascade connection mode, timer 40 output signal is forcibly selected for count clock.
Remarks 1. f : System clock oscillation frequency (ceramic/crystal oscillation)
X
2. f : System clock oscillation frequency (RC oscillation)
CC
CHAPTER 9 8-BIT TIMERS 30 AND 40
5 4 3
TCL302 TCL301 TCL300
TM30 count operation control
TCL300
When operating at f
6
0 f /2 (78.1 kHz)
X
8
1 f /2 (19.5 kHz)
X
0 Timer 40 match signal
1 Carrier clock generated by timer 40
Setting prohibited
TMD401 TMD400
0 0 Discrete mode
0 1 Cascade connection mode
1 1 Carrier generator mode
1 0 PWM output mode
Setting prohibited
User's Manual U14826EJ5V0UD
2 1 0
TMD301 TMD300 0
Note 1
Selection of timer 30 count clock
= 5.0 MHz When operating at f
X
6
f /2 (15.6 kHz)
CC
8
f /2 (3.91 kHz)
CC
Selection of timer 30, timer 40 operating mode
Address After reset R/W
FF52H 00H R/W
= 1.0 MHz
CC
Note 2
89