at89c51rc2-slsil ATMEL Corporation, at89c51rc2-slsil Datasheet - Page 39

• Manufacturer Part Number: at89c51rc2-slsil
• Description: 8-bit Microcontroller With 16k/ 32k Bytes Flash
• Manufacturer: ATMEL Corporation

PCA Capture Mode
Figure 13. PCA Capture Mode
4180E–8051–10/06
Cex. n
CF
ECOMn
CR
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
(see Figure 13).
CAPPn
CAPNn MATn TOGn PWMn ECCFn
CCF4 CCF3 CCF2 CCF1 CCF0
Capture
CCAPMn, n = 0 to 4
0xDA to 0xDE
CCON
0xD8
CCAPnH
PCA Counter/Timer
CH
AT89C51RB2/RC2
CCAPnL
CL
PCA IT
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