W921E840A Datasheet, PDF (34/58 Pages) Winbond – 4-BIT MICROCONTROLLER

W921E840A/W921C840
6.11.4 TM3
TM3 can perform the following functions:
1. 2 to19 order divider
2. Auto-reload timer
f ^System
Clock
SYS
1/4
11-bit Prescaler
f TM3
8 Order Divider
Interrupt Control
Register
TM3 Interrupt
Logic
High Speed
Clock
TM3 Control
Register
TM3 Set Register
(8 bits)
TM3 Control
Logic
TM3CR register: (address = 02FH, default data = 0H)
b3
b2
b1
b0
b3 b2 b1 b0 Input frequency (f_TM3 )
0000
fsys/2 Hz
0001
fsys/4 Hz
0010
fsys/8 Hz
0011
fsys/16 Hz
0100
fsys/32 Hz
0101
fsys/64 Hz
0110
fsys/128 Hz
0111
fsys/256 Hz
1000
fsys/512 Hz
1 0 0 1 fsys/1024 Hz
1 0 1 0 fsys/2048 Hz
The TM3 set register is divided into TM3 MSB data register (TM3MSB register, address = 030H,
default = 0FH) and TM3 LSB data register (TM3LSB register, address = 031H, default = 0FH).
The format of the status of TM3 register (STTM3) is described below:
STTM3 register: (address = 032H, default data = 0H)
b3
b2
b1
b0
Reserved
Reserved
0: TM3 auto-reload disable
1: TM3 auto-reload enable
0: TM3 stop
1: TM3 start
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