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Rockwell Automation 6008-SI IBM PC I/O SCNNR 6008-SI User Manual

Page 63

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Chapter 6

Discrete I/O

6-8

clrbit

Use this routine to write a zero bit into the output image table.

Calling sequence:

clrbit(

rack, group, bit

);

Arguments:

rack:

an integer 0 to 7, the logical rack number.

group:

an integer 0 to 7, the module group number.

bit:

an integer 0 to 15 (decimal) or 0 to 17 (octal), the bit number.

Returned values:

none.

Note:

clrbit

is a macro that compiles into a call on putbit with a

constant data value of 0.

putbyte

Use this routine to write an 8-bit byte to the output image table.

Calling sequence:

putbyte(

data, rack, group, hilow

);

Arguments:

data:

an unsigned integer whose low order byte is written to the output

image table.

rack:

an integer 0 to 7, the logical rack number.

group:

an integer 0 to 7, the module group number.

hilow:

the logical constant HI (1) or LO (0) to select the high or low

byte. The high byte is slot 1 (terminals 17-10) of the module group; the
low byte is slot 0 (terminals 07-00).

Returned values:

none.