C8051F989-GUR Silicon Labs, C8051F989-GUR Datasheet - Page 305

• Manufacturer Part Number: C8051F989-GUR
• Description: 8-bit Microcontrollers - MCU 4kB 512B RAM
• Manufacturer: Silicon Labs

Specifications of C8051F989-GUR

• Rohs: yes
• Core: 8051
• Data Bus Width: 8 bit
• Processor Series: C8051

Where F
PCA0MD. The lower byte of the capture/compare module is compared to the PCA counter low byte; on a
match, CEXn is toggled and the offset held in the high byte is added to the matched value in PCA0CPLn.
Frequency Output Mode is enabled by setting the ECOMn, TOGn, and PWMn bits in the PCA0CPMn
register. Note that the MATn bit should normally be set to 0 in this mode. If the MATn bit is set to 1, the
CCFn flag for the channel will be set when the 16-bit PCA0 counter and the 16-bit capture/compare
register for the channel are equal.
26.3.5. 8-bit, 9-bit, 10-bit and 11-bit Pulse Width Modulator Modes
Each module can be used independently to generate a pulse width modulated (PWM) output on its
associated CEXn pin. The frequency of the output is dependent on the timebase for the PCA counter/timer,
and the setting of the PWM cycle length (8, 9, 10 or 11-bits). For backwards-compatibility with the 8-bit
PWM mode available on other devices, the 8-bit PWM mode operates slightly different than 9, 10 and 11-
bit PWM modes. It is important to note that all channels configured for 8/9/10/11-bit PWM mode will
use the same cycle length. It is not possible to configure one channel for 8-bit PWM mode and another
for 11-bit mode (for example). However, other PCA channels can be configured to Pin Capture, High-
Speed Output, Software Timer, Frequency Output, or 16-bit PWM mode independently.
PCA0CPLn
Write to
Reset
PCA0CPHn
PCA
Write to
is the frequency of the clock selected by the CPS2–0 bits in the PCA mode register,
0
ENB
ENB
1
W
M
P
1
6
n
x
C
O
M
E
n
Figure 26.7. PCA Frequency Output Mode
PCA0CPMn
C
A
P
P
n
0 0 0
C
A
P
N
n
M
A
T
n
T
O
G
n
W
M
P
n
C
C
E
F
n
x
PCA Timebase
Enable
Rev. 1.1
Comparator
PCA0CPLn
PCA0L
8-bit
C8051F99x-C8051F98x
match
Enable
Adder
8-bit Adder
Toggle
TOGn
0
1
CEXn
PCA0CPHn
Crossbar
Port I/O
305