TS80C51RA2 Atmel Corporation, TS80C51RA2 Datasheet - Page 28

• Manufacturer Part Number: TS80C51RA2
• Description: High Performance 8-bit Microcontroller
• Manufacturer: Atmel Corporation

PCA Capture Mode
Figure 9. PCA Capture Mode
28
TS8xC51Rx2
Cex.n
CF
ECOMn
CR
Table 14. CH: PCA Counter High
Table 15. CL: PCA Counter Low
To use one of the PCA modules in the capture mode either one or both of the CCAPM
bits CAPN and CAPP for that module must be set. The external CEX input for the mod-
ule (on port 1) is sampled for a transition. When a valid transition occurs the PCA
hardware loads the value of the PCA counter registers (CH and CL) into the module's
capture registers (CCAPnL and CCAPnH). If the CCFn bit for the module in the CCON
SFR and the ECCFn bit in the CCAPMn SFR are set then an interrupt will be generated
(Refer to Figure 9).
Address 0E9H
Address 0F9H
CAPPn
CH
CL
CAPNn MATn TOGn PWMn ECCFn
CCF4 CCF3 CCF2 CCF1 CCF0
Reset value
Reset value
Capture
7
0
7
0
6
0
6
0
CCAPMn, n= 0 to 4
0xDA to 0xDE
CCON
0xD8
5
0
5
0
CCAPnH
PCA Counter/Timer
CH
4
0
4
0
CCAPnL
3
0
3
0
CL
2
0
2
0
PCA IT
4188A–8051–10/02
1
0
1
0
0
0
0
0