UPSD3212C, UPSD3212CV
Programmable Period 8-bit PWM
The PWM 4 channel can be programmed to pro-
vide a PWM output with variable pulse width and
period. The PWM 4 has a 16-bit Prescaler, an 8-
bit Counter, a Pulse Width Register, and a Period
Register. The Pulse Width Register defines the
PWM pulse width time, while the Period Register
defines the period of the PWM. The input clock to
the Prescaler is f
/2. The PWM 4 channel is as-
OSC
signed to Port 4.7.
Figure 37. Programmable PWM 4 Channel Block Diagram
DATA BUS
8
8
8
8-bit PWM4P
CPU RD/WR
8-bit PWM4W
Register
Register
(Period)
(Width)
8
8
8
8-bit PWM4
Comparator
Register
8-bit PWM4
Comparator
Register
Load
16-bit Prescaler
CPU RD/WR
Register
Port 4.7
(B4h, B3h)
PWM4
Control
8
8
16
PWMCON
Bit 6 (PWMP)
8-bit PWM4
Comparator
8-bit PWM4
Comparator
f
/ 2
OSC
Match
16-bit Prescaler
Counter
8
8
Load
PWMCON
Bit 5 (PWME)
8-bit Counter
Clock
Reset
AI07091
73/152
STMICROELECTRONICS [ ST ]
