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. |
TMOD | Timer/Counter 0 and 1 Mode |
| Register |
SFR Address | 89H |
00H | |
Bit Addressable | No |
Gate
C/T
M1
M0
Gate
C/T
M1
M0
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| Table XVI. TMOD SFR Bit Designations | |
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Bit | Name | Description |
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7 | Gate | Timer 1 Gating Control. | ||
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| Set by software to enable timer/counter 1 only while INT1 pin is high and TR1 control bit is set. | ||
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| Cleared by software to enable timer 1 whenever TR1 control bit is set. | ||
6 | C/T | Timer 1 Timer or Counter Select Bit. | ||
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| Set by software to select counter operation (input from T1 pin). | ||
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| Cleared by software to select timer operation (input from internal system clock). | ||
5 | M1 | Timer 1 Mode Select Bit 1 (Used with M0 Bit). | ||
4 | M0 | Timer 1 Mode Select Bit 0. | ||
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| M1 | M0 |
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| 0 | 0 | TH1 operates as an |
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| 0 | 1 | |
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| 1 | 0 | |
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| reloaded into TL1 each time it overflows. |
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| 1 | 1 | Timer/Counter 1 Stopped. |
3 | Gate | Timer 0 Gating Control. | ||
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| Set by software to enable timer/counter 0 only while INT0 pin is high and TR0 control bit is set. | ||
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| Cleared by software to enable Timer 0 whenever TR0 control bit is set. | ||
2 | C/T | Timer 0 Timer or Counter Select Bit. | ||
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| Set by software to select counter operation (input from T0 pin). | ||
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| Cleared by software to select timer operation (input from internal system clock). | ||
1 | M1 | Timer 0 Mode Select Bit 1. | ||
0 | M0 | Timer 0 Mode Select Bit 0. | ||
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| M1 | M0 |
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| 0 | 0 | TH0 operates as an |
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| 0 | 1 | |
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| prescaler |
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| 1 | 0 | |
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| be reloaded into TL0 each time it overflows. |
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| 1 | 1 | TL0 is an |
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| bits. TH0 is an |
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REV. B |