W83C553F Datasheet, PDF (106/159 Pages) Winbond – SYSTEM I/O CONTROLLER WITH PCI ARBITER

W83C553F
Electrical Specifications
Counter Status Register
Function:
Each counter's status byte can be read following a timer Read Back command, as programmed in the
Timer Control Register (43h).
Type:
Read back
Bit Description:
Bit 7:
Bit 6:
Bits [5:4]:
Bits [3:1]:
Bit 0:
OUT. Count Out Status. This bit indicates the Counter Out pin state. When set to "1", the
OUT pin of the counter is also a "1". When set to "0", the OUT pin of the counter is also a "0".
NULLCOUNT.
R/W. Read/Write Selection Status. These bits reflect the read/write selection made through
bits [5:4] of the control register. The binary codes returned, during the status read, match the
codes used to program the counter read/write selection.
Bit 5
0
0
1
1
Bit 4
0
1
0
1
Function
Counter Latch command
R/W Least Significant Byte (LSB)
R/W Most Significant Byte (MSB)
R/W LSB then MSB
M. The Mode Selection Status bits return the counter mode programming. The binary code
returned matches the code used to program the counter mode, as listed under the bit function
above.
Bit 3
0
0
x
x
1
1
Bit 2
0
0
1
1
0
0
Bit 1
0
1
0
1
0
1
Mode
0
1
2
3
4
5
BCD. The countdown method is binary when this bit is "0", and Binary Coded Decimal (BCD)
when this bit is "1".
WINBOND SYSTEMS LABORATORY
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