Rockwell Automation 1771-N SERIES High Resolution Analog Module User Manual User Manual
Page 102
Block Transfer Write and Block Transfer Read Configurations for 8 Output/0 Input 1771-N Series Modules
C–6
Publication 1771ĆUM127B-EN-P - December 2002
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
Word/Dec. Bit
00
01
02
03
04
05
06
07
10
11
12
13
14
15
16
17
Word/Octal Bit
18
Unused = 0
Bad
Calib
Bad
Prog
Bad
Data
Rate
Alarm
High
Clamp
Low
Clamp
Unused = 0
19
Channel 8 Raw Count sent to DAC
20-27
For factory use only
Block Transfer Read Bit/Word Description for 8 Output Module
Word
Decimal Bit
(Octal Bit)
Definition
Word 0
Bits 00-15
(00-17)
Always 8800 Hexadecimal
Bit 00-05
Not used. Always 0
Bit 06
Bad structure. This bit is set if there is an error in the BTW
header.
Bit 07
Bad program. This bit is set if any of the module level
programming data is illegal.
Word 1
Bit 08 (10)
Module fault. This bit is set if any of the programming data sent
to the module in the most recent BTW was illegal, or if one or
more channels has the bad calibration bit set.
Bits 09-10
(11-12)
Program verify. Indicates the result of verify request.
00 = verify not requested;
10 = verify failed;
11 = verify succeeded
Bit 11 (13)
I/O reset. This bit is set whenever the I/O reset line on the
backplane is asserted.
Bit 12 (14)
RTS timeout. This bit is set if a BTR was not requested of the
module within the RTS sample time.
Bit 13 (15)
Module alarm. This bit is set if there is an alarm bit set for one
or more channels. The input alarm bits are low, high alarm and
rate alarm. The output channel alarm bits are low and high
clamp, and the rate limit alarm.
Word 1 continued
Bit 14 (16)
Bad channel data. This bit is set if the module is in BCD mode
and one or more of the input data values sent in the last BTW
are not legal BCD values.
Bit 15 (17)
Powerup bit. This bit is set until a BTW with programming data
is received by the module.
Word 2
Always 8000 hexadecimal.
Word 3
Not used. Always 0
Word 4
Bit 00-03
Not used. Always 0
Bit 04
Low clamp. This bit is set if alarms are enabled and the output
data is lower than the low clamp value.
Bit 05
High clamp. This bit is set if alarms are enabled and the output
data is higher than the high clamp value.