AT89C51RE2 Atmel Corporation, AT89C51RE2 Datasheet - Page 88

• Manufacturer Part Number: AT89C51RE2
• Manufacturer: Atmel Corporation

Specifications of AT89C51RE2

• Flash (kbytes): 128 Kbytes
• Max. Operating Frequency: 60 MHz
• Cpu: 8051-12C
• Max I/o Pins: 34
• Spi: 1
• Uart: 2
• Sram (kbytes): 8.25
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 5.5
• Timers: 4
• Isp: UART/OCD
• Watchdog: Yes

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AT89C51RE2
Table 57. PCA Module Modes (CCAPMn Registers)
There are two additional registers associated with each of the PCA modules. They are CCAPnH
and CCAPnL and these are the registers that store the 16-bit count when a capture occurs or a
compare should occur. When a module is used in the PWM mode these registers are used to
control the duty cycle of the output (See Table 58 & Table 59).
Table 58. CCAPnH Registers (n = 0-4)
CCAP0H - PCA Module 0 Compare/Capture Control Register High (0FAh)
CCAP1H - PCA Module 1 Compare/Capture Control Register High (0FBh)
CCAP2H - PCA Module 2 Compare/Capture Control Register High (0FCh)
CCAP3H - PCA Module 3 Compare/Capture Control Register High (0FDh)
CCAP4H - PCA Module 4 Compare/Capture Control Register High (0FEh)
Reset Value = 0000 0000b
Not bit addressable
ECOMn
Number
X
X
X
0
1
1
1
1
Bit
7-0
7
-
CAPPn
0
1
0
1
0
0
0
0
Mnemonic
Bit
6
-
-
CAPNn
0
0
1
1
0
0
0
0
Description
PCA Module n Compare/Capture Control
MATn
5
-
CCAPnH Value
0
0
0
0
1
1
0
1
TOGn
0
0
0
0
0
1
0
X
4
-
PWMm
0
0
0
0
0
0
1
0
3
-
ECCFn
X
X
X
X
X
X
0
0
Module Function
trigger on CEXn
CEXn
mode.
No Operation
16-bit capture by a positive-edge
16-bit capture by a negative trigger on
16-bit capture by a transition on CEXn
16-bit Software Timer / Compare
16-bit High Speed Output
8-bit PWM
Watchdog Timer (module 4 only)
2
-
1
-
7663E–8051–10/08
0
-