AT83C5134 Datasheet, PDF (40/171 Pages) ATMEL Corporation – 8-bit Microcontroller with Full Speed USB Device

Figure 19. PCA Timer/Counter
F_{CLK PERIPH}/6
F_{CLK PERIPH}/2
T0 OVF
P1.2
To PCA
modules
overflow
It
CH
CL
16 Bit Up Counter
CIDL WDTE
CPS1 CPS0 ECF
CMOD
0xD9
Idle
CF CR
CCF4 CCF3 CCF2 CCF1 CCF0
CCON
0xD8
Table 39. CMOD Register
CMOD - PCA Counter Mode Register (D9h)
7
6
5
4
3
CIDL
WDTE
-
-
-
2
CPS1
1
CPS0
0
ECF
Bit
Number
Bit
Mnemonic Description
Counter Idle Control
7
CIDL
Cleared to program the PCA Counter to continue functioning during idle Mode.
Set to program PCA to be gated off during idle.
Watchdog Timer Enable
6
WDTE Cleared to disable Watchdog Timer function on PCA Module 4.
Set to enable Watchdog Timer function on PCA Module 4.
5
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
4
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
3
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
2
CPS1 PCA Count Pulse Select
CPS1CPS0 Selected PCA input
0
0
Internal clock f_{CLK PERIPH}/6
1
CPS0
0
1
Internal clock f_{CLK PERIPH}/2
1
0 Timer 0 Overflow
1
1
External clock at ECI/P1.2 pin (max rate = f_{CLK PERIPH}/ 4)
PCA Enable Counter Overflow Interrupt
0
ECF
Cleared to disable CF bit in CCON to inhibit an interrupt.
Set to enable CF bit in CCON to generate an interrupt.
Reset Value = 00XX X000b
Not bit addressable
40 AT83C5134/35/36
7683B–USB–03/07