Rockwell Automation 1794-APB/B FLEX I/O PROFIBUS Adapter Module User Manual User Manual
Page 82
2–62
How Communication Takes Place and I/O Image Table Mapping
Publication 1794ĆUM057B-EN-P - November 2001
Definition
Bit
Word
Write
Word 1
Control Word 0 - Control word for setting the function of counter 0.
Word 1
Bits 00
Pulse counting and period time measurement selection for Channel 0 -
0 = pulse counting and period time measurement selected
1 = period time measurement selected
Bits 01
Pulse counting and period time measurement selection for Channel 1 -
0 = pulse counting and period time measurement selected
1 = period time measurement selected
Bits 02
Pulse counting and period time measurement selection for Channel 2 -
0 = pulse counting and period time measurement selected
1 = period time measurement selected
Bits 03
Pulse counting and period time measurement selection for Channel 3 -
0 = pulse counting and period time measurement selected
1 = period time measurement selected
Bits 04-15
(04-17)
Reserved
Write
Word 2
Bit 00
Clock frequency for period time measurement - Channel 0 -
0 = period time measurement with 10MHz internal clock selected
1 = period time measurement with 1MHz internal clock selected
Bits 01-03
03
02 01
Number of periods for measurement - Channel 0
0
0
0
1 period
0
0
1
2 periods
0
1
0
4 periods
0
1
1
8 periods
1
0
0
16 periods
1
0
1
32 periods
1
1
0
64 periods
1
1
1
128 periods
Bit 04
Clock frequency for period time measurement - Channel 1 - refer to bit 00.
Bits 05-07
Selection of Number of periods for measurement - Channel 1 - se e bits 01-03 above
Bit 08 (10)
Clock frequency for period time measurement - Channel 2 - refer to bit 00.
Bits 09-11
(11-13)
Selection of Number of periods for measurement - Channel 2 - se e bits 01-03 above
Bit 12 (14)
Clock frequency for period time measurement - Channel 1 - refer to bit 00.
Bits 13-15
(15-17)
Selection of Number of periods for measurement - Channel 1 - se e bits 01-03 above