8254B CONTROL REGISTER
BADR3 + Bh
WRITE ONLY
D0
D1
D2
D3
D4
D5
D6
D7
0
1
3
2
4
5
6
7
The control register is used to set the operating Modes of 8254B Counters 0,1 & 2. A counter is configured by writing the
correct Mode information to the Control Register, then the proper count data must be written to the specific Counter Regis-
ter.
The Counters on the 8254 are 16-bit devices. Since the interface to the 8254 is only 8-bits wide, Count data is written to the
Counter Register as two successive bytes. First the low byte is written, then the high byte. The Control Register is 8-bits
wide. Further information can be obtained on the 8254 data sheet, available from Intel or Harris.
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