Rockwell Automation 1794-VHSC 1794 FLEX I/O Very High Speed Counter Module User Manual User Manual
Page 51
Rockwell Automation Publication 1794-UM010D-EN-E - July 2013
43
Communicate With Your Module
Word 1
Filter Selection – Only 1 filter selection can be chosen at a time. Frequency = 50% duty cycle.
Bits 00…03
03
02
01
00
Counter 0
Bits 08…11
(10…13)
11
(13)
10
(12)
09
(11)
08
(10)
Counter 1
0
0
0
0
No filter
0
0
0
1
50 kHz (10
μ
s + 0
μ
s/-1.6
μ
s)
0
0
1
0
5 kHz (100
μ
s + 0
μ
s/-13.2
μ
s)
0
1
0
0
500 Hz (1.0 ms + 0 ms/-1.25
μ
s)
1
0
0
0
50 Hz (10.0 ms + 0 ms/-1.25 ms)
Bit 12 (14)
Input A filter bit (AF) – 0 = not filtered; 1 = apply filter to input
Bit 13 (15)
Input B filter bit (BF) – 0 = not filtered; 1 = apply filter to input
Bit 14 (16)
Input Z filter bit (ZF) – 0 = not filtered; 1 = apply filter to input
Bit 15 (17)
Set to 0.
Word 2
Bits 00…15
(00…17)
Time base – Sets the fundamental time base for both counters. Resolution in ms, with a minimum of 10 ms intervals
(10 ms = 10; 1 s = 1000).
Time base must be entered when PWM and rate measurement are configured. The maximum programmed
value is 3000.
Word 3
Bits 00…15
(00…17)
Channel 0 Gate interval – Sets the individual counter gate interval using the time base setting as its time unit.
Actual gate interval is time base X gate interval (for instance, time base of 10 X gate interval of 5 = 50 ms). Maximum
value is 3 s.
Gate interval must be entered when PWM and rate measurement are configured.
Word 4
Bits 00…15
(00…17)
Channel 1 Gate interval – Sets the individual counter gate interval using the time base setting as its time unit.
Actual gate interval is time base X gate interval (for instance, time base of 10 X gate interval of 5 = 50 ms). Maximum
value is 3 s.
Gate interval must be entered when PWM and rate measurement are configured.
Word 5
Bits 00…15
(00…17)
Do not use – reserved.
Word 6 and 7
Bits 00…15
(00…17)
Channel 0 Rollover – Sets the number of counts the counter accumulates before rolling over. For example, a setting
of 1000 produces a count sequence of 998, 999, 0, 1, 2... while incrementing; and 2, 1, 0, 999, 998... while
decrementing. Rollover is a 32-bit number with a usable range of 16,777,216. In PWM, this value is zero; in count, X1
encoder, X2 encoder and X4 encoder configurations, it must be some specified nonzero number. The value doesn.t
matter in period/rate, continuous/rate and rate measurement configurations.
Word 8 and 9
Bits 00…15
(00…17)
Channel 1 Rollover – Sets the number of counts the counter accumulates before rolling over. For example, a setting
of 1000 produces a count sequence of 998, 999, 0, 1, 2... while incrementing; and 2, 1, 0, 999, 998... while
decrementing. Rollover is a 32-bit number with a usable range of 16,777,216. In PWM, this value is zero; in count, X1
encoder, X2 encoder and X4 encoder configurations, it must be some specified nonzero number. The value doesn.t
matter in period/rate, continuous/rate and rate measurement configurations.
Word 10 and 11 Bits 00…15
(00…17)
Channel 0 Preset – This word sets the preset value the counter is loaded with when CP is asserted. This number has
a range of 0
≤
value
≤
16,777,216.
Word 12 and 13 Bits 00…15
(00…17)
Channel 1 Preset – This word sets the preset value the counter is loaded with when CP is asserted. This number has
a range of 0
≤
value
≤
16,777,216.
Configuration Word Definition
Configuration
Word
Bit
Definition