83C754 Datasheet, PDF (13/26 Pages) NXP Semiconductors – 80C51 8-bit microcontroller family 4K/256 OTP/ROM, DAC, comparator, UART, reference

Philips Semiconductors
80C51 8-bit microcontroller family
4K/256 OTP/ROM, DAC, comparator, UART, reference
Preliminary specification
83C754/87C754
CCAPMn Address CCAPM 0DEH
Reset Value = X000 0000B
Not Bit Addressable
––
ECOM
Bit:
7
6
CAPP
5
CAPN
4
MAT
3
TOG
2
PWM
1
ECCF
0
Symbol Function
–
ECOM
CAPP
CAPN
MAT
TOG
PWM
ECCF
Not implemented, reserved for future use*.
Enable Comparator. ECOM = 1 enables the comparator function.
Capture Positive, CAPP = 1 enables positive edge capture.
Capture Negative, CAPN = 1 enables negative edge capture.
Match. When MAT = 1, a match of the PCA counter with this module’s compare/capture register causes the CCF bit in
CCON to be set, flagging an interrupt.
Toggle. When TOG = 1, a match of the PCA counter with this module’s compare/capture register causes the CEX pin
to toggle.
Pulse Width Modulation Mode. PWM4 = 1 enables the CEX pin to be used as a pulse width modulated output.
Enable CCF interrupt. Enables compare/capture flag CCF in the CCON register to generate an interrupt.
NOTE:
*User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features. In that case, the reset or inactive value of the new
bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate.
SU00677A
Figure 10. CCAPM: PCA Modules Compare/Capture Registers
–
ECOM CAPP CAPN MAT
TOG
PWM ECCF
MODULE FUNCTION
X
0
0
0
0
0
0
0
No operation
X
X
1
0
0
0
0
X
16-bit capture by a positive-edge trigger on CEX
X
X
0
1
0
0
0
X
16-bit capture by a negative trigger on CEX
X
X
1
1
0
0
0
X
16-bit capture by a transition on CEX
X
1
0
0
1
0
0
X
16-bit Software Timer
X
1
0
0
1
1
0
X
16-bit High Speed Output
X
1
0
0
0
0
1
0
8-bit PWM
X
1
0
0
1
X
0
X
Watchdog Timer
Figure 11. PCA Module Modes (CCAPM Register)
CEX
CF
CR
––
CCF
––
––
––
––
CCON
(D8H)
(TO CCF)
PCA INTERRUPT
PCA TIMER/COUNTER
CH
CL
CAPTURE
1998 Apr 23
CCAPH
––
ECOM CAPP
CAPN
MAT
TOG
PWM
ECCF
CCAPM
0
0
0
0
Figure 12. PCA Capture Mode
13
CCAPL
SU00678A