C8051F997-GUR Silicon Labs, C8051F997-GUR Datasheet - Page 303

• Manufacturer Part Number: C8051F997-GUR
• Description: 8-bit Microcontrollers - MCU 8kB 14-CH CDC
• Manufacturer: Silicon Labs

Specifications of C8051F997-GUR

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

26.3.2. Software Timer (Compare) Mode
In Software Timer mode, the PCA counter/timer value is compared to the module's 16-bit capture/compare
register (PCA0CPHn and PCA0CPLn). When a match occurs, the Capture/Compare Flag (CCFn) in
PCA0CN is set to logic 1. An interrupt request is generated if the CCFn interrupt for that module is
enabled. The CCFn bit is not automatically cleared by hardware when the CPU vectors to the interrupt
service routine, and must be cleared by software. Setting the ECOMn and MATn bits in the PCA0CPMn
register enables Software Timer mode.
Important Note About Capture/Compare Registers: When writing a 16-bit value to the PCA0
Capture/Compare registers, the low byte should always be written first. Writing to PCA0CPLn clears the
ECOMn bit to 0; writing to PCA0CPHn sets ECOMn to 1.
PCA0CPLn
Write to
Reset
PCA0CPHn
Write to
0
ENB
ENB
1
W
M
P
1
6
n
Figure 26.5. PCA Software Timer Mode Diagram
x
E
C
O
M
n
PCA0CPMn
C
A
P
P
n
0 0
C
A
P
N
n
M
A
T
n
O
G
T
n
0 0
P
W
M
n
C
C
E
F
n
x
Enable
PCA
Timebase
Rev. 1.1
PCA0CPLn
PCA0L
16-bit Comparator
C8051F99x-C8051F98x
PCA0CPHn
PCA0H
Match
C
F
C
R
PCA0CN
0
1
C
C
F
2
C
C
F
1
C
C
F
0
PCA Interrupt
303