Single bit set/reset feature, Figure 4-1. control-word formats, Table 4-1. pc-dio-24 address map – National Instruments PC-DIO-24 User Manual
Page 34: Figure 4-1, Control-word formats
Register-Level Programming
Chapter 4
PC-DIO-24 User Manual
4-4
© National Instruments Corporation
D2
D1
D0
D5
D4
D3
D7
D6
(high nibble)
1 = input
0 = output
Control Word
Flag
1 = mode set
00 = mode 0
01 = mode 1
1X = mode 2
Mode Selection
1 = input
0 = output
Port A
Port C
(low nibble)
1 = input
0 = output
Port C
0 = mode 0
1 = mode 1
Mode Selection
Group A
Group B
Port B
1 = input
0 = output
Flag
D2
D1
D0
X
X
D3
D7
X
0 = bit set/reset
1 = set
0 = reset
(000)
(001)
(010)
:
:
(111)
Control Word
Bit Select
Bit Set/Reset
a. Mode Set Word Format
b. Bit Set/Reset Word Format
Figure 4-1. Control-Word Formats
Single Bit Set/Reset Feature
Table 4-2 shows the control words for setting or resetting each bit in port C. Notice that bit 7 of
the control word is cleared when programming the set/reset option for the bits of port C.