Technical data

MOTOROLA MC68HC912B32
66 MC68HC912B32TS/D
CON01 — Concatenate PWM Channels 0 and 1
When concatenated, channel 0 becomes the high-order byte and channel 1 becomes the low-order
byte. Channel 0 output pin is used as the output for this 16-bit PWM (bit 0 of port P). Channel 1 clock-
select control bits determine the clock source.
0 = Channels 0 and 1 are separate 8-bit PWMs.
1 = Channels 0 and 1 are concatenated to create one 16-bit PWM channel.
PCKA2 – PCKA0 — Prescaler for Clock A
Clock A is one of two clock sources which may be used for channels 0 and 1. These three bits determine
the rate of clock A, as shown in Table 22.
PCKB2 – PCKB0 — Prescaler for Clock B
Clock B is one of two clock sources which may be used for channels 2 and 3. These three bits determine
the rate of clock B, as shown in Table 22.
Read and write anytime.
PCLK3 — PWM Channel 3 Clock Select
0 = Clock B is the clock source for channel 3.
1 = Clock S1 is the clock source for channel 3.
PCLK2 — PWM Channel 2 Clock Select
0 = Clock B is the clock source for channel 2.
1 = Clock S1 is the clock source for channel 2.
PCLK1 — PWM Channel 1 Clock Select
0 = Clock A is the clock source for channel 1.
1 = Clock S0 is the clock source for channel 1.
PCLK0 — PWM Channel 0 Clock Select
0 = Clock A is the clock source for channel 0.
1 = Clock S0 is the clock source for channel 0.
If a clock select is changed while a PWM signal is being generated, a truncated or stretched pulse may
occur during the transition.
Table 22 Clock A and Clock B Prescaler
PCKA2
(PCKB2)
PCKA1
(PCKB1)
PCKA0
(PCKB0)
Value of
Clock A (B)
000 P
001 P ÷ 2
010 P ÷ 4
011 P ÷ 8
100 P ÷ 16
101 P ÷ 32
110 P ÷ 64
111P ÷ 128
PWPOL — PWM Clock Select and Polarity $0041
Bit 7 6 5 4 3 2 1 Bit 0
PCLK3 PCLK2 PCLK1 PCLK0 PPOL3 PPOL2 PPOL1 PPOL0
RESET: 0 0 0 0 0 0 0 0