Analog Devices MicroConverter ADuC812 User Manual page 30

ADuC812
User configuration and control of all Timer operating modes is
achieved via three SFRs, namely:
TMOD, TCON: Control and configuration for
Timers 0 and 1.
T2CON: Control and configuration for
Timer 2.
G a e t C T /
Bit Name
7 Gate
6 C/T
5 M1
4 M0
3 Gate
2 C/T
1 M1
0 M0
M 1 M 0
Table XVI. TMOD SFR Bit Designations
Description
Timer 1 Gating Control.
Set by software to enable timer/counter 1 only while INT1 pin is high and TR1 control bit is set.
Cleared by software to enable timer 1 whenever TR1 control bit is set.
Timer 1 Timer or Counter Select Bit.
Set by software to select counter operation (input from T1 pin).
Cleared by software to select timer operation (input from internal system clock).
Timer 1 Mode Select Bit 1 (Used with M0 Bit).
Timer 1 Mode Select Bit 0.
M1 M0
0 0 TH1 operates as an 8-bit timer/counter. TL1 serves as 5-bit prescaler.
0 1 16-Bit Timer/Counter. TH1 and TL1 are cascaded; there is no prescaler.
1 0 8-Bit Auto-Reload Timer/Counter. TH1 holds a value which is to be
reloaded into TL1 each time it overflows.
1 1 Timer/Counter 1 Stopped.
Timer 0 Gating Control.
Set by software to enable timer/counter 0 only while INT0 pin is high and TR0 control bit is set.
Cleared by software to enable Timer 0 whenever TR0 control bit is set.
Timer 0 Timer or Counter Select Bit.
Set by software to select counter operation (input from T0 pin).
Cleared by software to select timer operation (input from internal system clock).
Timer 0 Mode Select Bit 1.
Timer 0 Mode Select Bit 0.
M1 M0
0 0 TH0 operates as an 8-bit timer/counter. TL0 serves as 5-bit prescaler.
0 1 16-Bit Timer/Counter. TH0 and TL0 are cascaded; there is no
prescaler
1 0 8-Bit Auto-Reload Timer/Counter. TH0 holds a value which is to
be reloaded into TL0 each time it overflows.
1 1 TL0 is an 8-bit timer/counter controlled by the standard timer 0 control
bits. TH0 is an 8-bit timer only, controlled by Timer 1 control bits.
TMOD Timer/Counter 0 and 1 Mode
Register
SFR Address 89H
Power-On Default Value 00H
Bit Addressable No
G a e t C T / M 1 M 0