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1.3.7 Programmable Timer/Counter
Type : 82C54 -8 programmable timer/counter
Counters: The counter1 and counter2 are cascaded as a 32 bits pacer timer.
The counter0 is used as user timer/counter. The software driver use counter0
to implement a machine independent timer.
Clock input frequency : DC to 10 MHz
Pacer output : 0.00047Hz to 0.5MHz
Input, gate : TTL compatible
Internal Clock : 2M Hz
1.3.8 Direct Memory Access Channel (DMA)
Level : CH1 or CH3, jumper selectable
Enable : via DMA bit of control register
Termination : by interrupt on T/C
Transfer rate : 100K conversions/sec.(DOS Software manual, sec. 4.11)
A-812PG Hardware Manual (Ver.1.2, Sep/2005, IPH-004-12) -----
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