Intel MCS 51 User Manual

8XC51FXHARDWAREDESCRIPTION
Table 12. CCAPMn: PCAModules Compare/Capture Regiatere
CCAPMn Address CCAPMO ODAH
ResetValue = XOOO00006
(n = O-4)
CCAPMI ODBH
CCAPM2
ODCH
CCAPM3 ODDH
CCAPM4 ODEH
NotBitAddressable
—
ECOMn
CAPPn CAPNn MATn
TOGn PWMn ECCFn
Bit
7 6 5 4 3 2 1
0
Symbol Funotion
—
ECOMn
CAPPn
CAPNn
MATn
TOGn
PWMn
ECCFn
NOTE:
Notimplemented,reservedforfutureuse*.
Enablecomparator.ECOMn= 1enablesthecomparatorfun~”on.
CapturePositive,CAPPn= 1enablespositiveedgecapture.
CaptureNegative,CAPNn= 1enablesnegativeedgecapture.
Match.WhenMATn= 1,a matchofthePCAcounterwiththismodule’scompare/cepture
registercausestheCCFnbitinCCONto beset,flagginganinterrupt.
Toggle.WhenTOGn= 1,a matchofthePCAcounterwiththismodule’scompare/capture
registercausestheCEXnpinto toggle.
Pulse Width Modulation Mode. PWMn = 1 enables the CEXn pin to beusedasapulsewidth
modulatedoutput.
EnableCCFinterrupt.Enablescompare/captureflagCCFnintheCCONregisterto generate
aninterrupt.
*User softwareshoutdnot write Is to reservedbits.Thesebite maybe usedin future8051 familyproductsto invoke
new features.Inthat case, the reset or inscttievalueof the new bitwillbe O,and itsacfNe valuewillbe 1. The value
read froma reservedbitis indeterminate.
Tabfe 13. PCA Module Modes (CCAPMn Regiater)
I - lECOMnlCAPPnlCAPNnlMATnl TOGnlPWMnlECCFnl
ModuleFunction
I
I x I o I o I o I o I O I o I o INoot)erstion
I
x x
1 0 0
0 0
x
16-bit capture bya postive-edgetriggeron CEXn
x
x
o
1
0 0
0
x Ie-bitcapturebyanegative-edgetriggeron
CEXn
x x 1
1
0
0 0
x 16-bifcapturebyatrsnsition on CEXn
x 1
I
o
0 1
I
Ololx
16-bifSoftwareTimer
x 1 0
0 1
1
0 x
16-bit High Speed Output
x I 1 I o 0 0
0 1 0
!8-bit PWM
[
1 1 1
1 1
t I
x 1 0 0 1
x Olx
WatchdogTimer
X = Don’t Care
5-23

Intel MCS 51 Specifications

General

Brand	Intel
Model	MCS 51
Category	Microcontrollers
Language	English