Rockwell Automation 1771-N SERIES High Resolution Analog Module User Manual User Manual
Page 179
Block Transfer Write and Block Transfer Read Configurations for 7 Output/1 Input 1771-N Series Modules
K–7
Publication 1771ĆUM127B-EN-P - December 2002
Block Transfer Read Bit/Word Descriptions for 7 Output/1 Input
Modules
Word
Decimal Bit
(Octal Bit)
Definition
Word 0
Bits 00-15
(00-17)
Constant = 8800 hexadecimal
Bits 00-05
Not used. Always 0
Bit 06
Bad structure. This bit is set if there is an error in the BTW
header.
Word 1
Bit 07
Bad program. This bit is set if any of the module level
programming data is illegal.
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.
Word 1 continued
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.
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 a legal BCD value.
Bit 15 (17)
Powerup bit. This bit is set until a BTW with programming data
is received by the module.
Bit 00
Cold junction compensation (CJC) underrange bit. This bit is
set if the CJC temperature is below 0
o
C.
Word 2
Bit 01
Cold junction compensation (CJC) overrange bit. This bit is set
if the CJC temperature is above 70
o
C.
Bits 02-14
(02-16)
Not used. Always 0.
Bit 15 (17)
Always 1.
Word 3
Bits 00-15
(00-17)
Cold junction temperature. Units of 0.01 degrees C or 0.1
degrees F. (0.1 degrees C or 1.0 degrees F in BCD.)