C8051F581-IMR Silicon Labs, C8051F581-IMR Datasheet - Page 336

• Manufacturer Part Number: C8051F581-IMR
• Description: 8-bit Microcontrollers - MCU 50MIPS 128kB 8kB SPI
• Manufacturer: Silicon Labs

Specifications of C8051F581-IMR

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

C8051F58x/F59x
29.3.2. Software Timer (Compare) Mode
In Software Timer mode, the PCA1 counter/timer value is compared to the module's 16-bit capture/com-
pare register (PCA1CPHn and PCA1CPLn). When a match occurs, the Capture/Compare Flag (CCFn) in
PCA1CN 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 ser-
vice routine, and must be cleared by software. Setting the ECOM1n and MAT1n bits in the PCA1CPMn
register enables Software Timer mode.
Important Note About Capture/Compare Registers : When writing a 16-bit value to the PCA1 Cap-
ture/Compare registers, the low byte should always be written first. Writing to PCA1CPLn clears the
ECOM1n bit to 0; writing to PCA1CPHn sets ECOM1n to 1.
336
PCA1CPLn
Write to
Reset
PCA1CPHn
Write to
0
ENB
ENB
1
Figure 29.5. PCA1 Software Timer Mode Diagram
W
P
M
1
6
1
n
x
PCA1CPMn
E
C
O
M
1
n
C
A
P
P
1
n
0 0
C
N
A
P
1
n
M
A
T
n
1
O
G
T
1
n
0 0
W
M
P
1
n
E
C
C
F
1
n
x
Enable
PCA1
Timebase
Rev. 1.2
PCA1CPLn
PCA1L
16-bit Comparator
PCA1CPHn
PCA1H
Match
C
F
1
C
R
1
PCA1CN
C
C
F
0
1
1
1
C
C
F
1
0
C
C
F
9
C
C
F
8
C
C
F
7
PCA1 Interrupt
C
C
F
6