Pca Capture Value/Compare Value Registers (Ccapnl, Ccapnh); Pca Pwm Mode Control Registers (Pca_Pwmn); Pca Operation Mode - STC micro STC8A8K64D4 Series Reference Manual

STC8A8K64D4 Series Manual
CCAPNn: PCAn Capture on falling edge enable bit
MATn: PCAn match function enable bit
TOGn: PCAn high speed pulse output function enable bit
PWMn: PCAn PWM output function enable bit
ECCFn: PCAn match/capture interrupt enable bit

18.2.5 PCA capture value/compare value registers (CCAPnL, CCAPnH)

Symbol Address
CCAP0L EAH
CCAP1L EBH
CCAP2L ECH
CCAP3L FD55H
CCAP0H FAH
CCAP1H FBH
CCAP2H FCH
CCAP3H FD56H
When the PCA capture function is enabled, CCAPnL and CCAPnH are used to save the count value (CL and CH) of
the PCA at the time of capture. When the PCA comparison function is enabled, the PCA controller compares the
current value in [CH,CL] and the value in [CCAPnH, CCAPnL], and the comparison result is given. When the
PCA match function is enabled, the PCA controller compares the current value in [CH, CL] with the value stored
in [CCAPnH, CCAPnL], and checks if they match (equal), then gives a match result.

18.2.6 PCA PWM mode control registers (PCA_PWMn)

Symbol Address
PCA_PWM0 F2H
PCA_PWM1 F3H
PCA_PWM2 F4H
PCA_PWM3 FD57H
EBSn[1:0]: PCAn PWM number of bits control
EBSn[1:0] PWM bits
00 8-bits PWM
01 7-bits PWM
10 6-bits PWM
11 10-bits PWM
XCCAPnH[1:0]: The 9
XCCAPnL[1:0]: The 9
EPCnH: The MSB of reload vaule in PWM mode (i.e. the 9
bit of 6-bit PWM, the 11
EPCnL: The MSB of comparison vaule in PWM mode (i.e. the 9
7 th bit of 6-bit PWM, the 11
Note: When updating the reload value of 10-bit PWM, write the upper two bits of XCCAPnH [1: 0] firstly and
then the lower 8 bits of CCAPnH [7: 0].

18.3 PCA Operation Mode

There are 4 groups of PCA modules in STC12Hseries of microcontrollers, and operation mode of each module can be
set independently. The mode settings are as follows:
-
ECOMn CAPPn CAPNn
- 0 0
- 1 0
- 1 1
- 1 0
B7 B6
B7 B6
EBS0[1:0]
EBS1[1:0]
EBS2[1:0]
EBS3[1:0]
Reload value
{EPCnH, CCAPnH[7:0]}
{EPCnH, CCAPnH[6:0]}
{EPCnH, CCAPnH[5:0]}
{EPCnH, XCCAPnH[1:0], CCAPnH[7:0]}
th th
bit and 10 bit of reload value of 10-bit PWM
th th
bit and 10 bit of comparison value of 10-bit PWM
th bit of 10-bit PWM)
th bit of 10-bit PWM)
CCAPMn
MATn TOGn PWMn
0 0 0
0 0 0
0 0 0
1 0 0
B5 B4 B3
B5 B4 B3
XCCAP0H[1:0] XCCAP0L[1:0]
XCCAP1H[1:0] XCCAP1L[1:0]
XCCAP2H[1:0] XCCAP2L[1:0]
XCCAP3H[1:0] XCCAP3L[1:0]
Comparison value
{EPCnL, CCAPnL[7:0]}
{EPCnL, CCAPnL[6:0]}
{EPCnL, CCAPnL[5:0]}
{EPCnL, XCCAPnL[1:0], CCAPnL[7:0]}
th
bit of 8-bit PWM, the 8
th
bit of 8-bit PWM, the 8
ECCFn
0 0
1 0 6/7/8/10 bit PWM mode, no interrupt
6/7/8/10 bit PWM mode, rising edge
1 1
interrupt
1 1 6/7/8/10 bit PWM mode, falling edge
B2 B1
B2 B1
EPC0H EPC0L
EPC1H EPC1L
EPC2H EPC2L
EPC3H EPC3L
th
bit of 7-bit PWM, the 7
th
bit of 7-bit PWM, the
Function of module
No operation
B0
B0
th
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