TS87C51RD2 ATMEL Corporation, TS87C51RD2 Datasheet - Page 25

• Manufacturer Part Number: TS87C51RD2
• Description: (TS8xC51Rx2) High Performance 8-bit Microcontroller
• Manufacturer: ATMEL Corporation

Figure 6-4.
4188E–8051–08/06
PCA Timer/Counter
Idle
Fosc /12
Fosc / 4
T0 OVF
P1.2
Table 6-4.
1.
2.
The CMOD SFR includes three additional bits associated with the PCA (See Figure 6-4 and
Table 6-4).
CIDL
WDTE
-
CPS1
CPS0
ECF
Symbol
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.
f
osc
Address 0D9H
CIDL
= oscillator frequency
CF
CMOD
CMOD: PCA Counter Mode Register
Function
Counter Idle control: CIDL = 0 programs the PCA Counter to continue functioning during idle Mode.
CIDL = 1 programs it to be gated off during idle.
Watchdog Timer Enable: WDTE = 0 disables Watchdog Timer function on PCA Module 4. WDTE = 1
enables it.
Not implemented, reserved for future use.
PCA Count Pulse Select bit 1.
PCA Count Pulse Select bit 0.
PCA Enable Counter Overflow interrupt: ECF = 1 enables CF bit in CCON to generate an interrupt.
ECF = 0 disables that function of CF.
CPS1
WDTE
0
0
1
1
CR
Reset value
CPS0
0
1
0
1
CCF4 CCF3 CCF2 CCF1 CCF0
Selected PCA input.
Internal clock f
Internal clock f
Timer 0 Overflow
External clock at ECI/P1.2 pin (max rate = f
CIDL
0
CPS1 CPS0
osc
osc
WDTE
16 bit up/down counter
/12 ( Or f
/4 ( Or f
0
CH
(2)
(1)
osc
osc
X
/2 in X2 Mode).
-
/6 in X2 Mode).
ECF
CL
CMOD
0xD9
CCON
0xD8
X
-
overflow
AT/TS8xC51Rx2
osc
/ 8)
X
-
To PCA
modules
CPS1
0
It
CPS0
0
ECF
0
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