Spectrum Controls 1769sc-HART Modules - Manual (Page 55)

Chapter 6: Module Data, Status, and Configuration
User’s Manual 0300217-03 Rev. A
6-3
that range.
Note: This bit can also be set if the high clamp value is reached or exceeded. The bit
will automatically clear when the channel command value
1 drops below the high clamp
value.
6.3.4 Under-Range Flag Bits U0 to U3 (Word 1)
Under-range bits for channels 0 through 3 are contained in word 1. They apply to all
output types. When set (1), the under-range flag bit indicates an output signal that is at
the minimum of its normal operating range for the represented channel or sensor. The
module automatically resets (0) when the under-range condition is cleared and the data
value is within the normal operating range.
Note: This bit can also be set if the low clamp value is reached or exceeded. The bit
will automatically clear when the channel command value
1 is above the low clamp
value. Refer to section 6.3.16 for more details.
6.3.5 Hold Last State Bits H0 to H3 (Word 1)
The hold last state bit will be set on the associated channel if the channel is configured to
output the last commanded value, and a fault or “run to program” condition is present.
Refer to Section 6.3.12 for more details.
6.3.6 Channel X
2
Command Value Echo (Words 2 to 5)
Data words 2 through 5 correspond to channels 0 through 3 respectively and contain the
current command value
1
stored in the module’s RAM memory for the associated channel.
These input words can be used as a handshake to verify that the module has received the
correct command value for the associated channel. The command value is defined in
section 6.4.1.
6.3.7 HART Packet Data (Words 6 to 25)
This block of twenty words contains the multiplexed HART packet data for all four
channels.
3
6.3.8 Message Slave Control (Word 26)
The message slave control word controls how data is returned from the module after
sending a message using output words 6 through 27
3 .
6.3.9 Message Reply Size (Word 27)
The message response size indicates the number of bytes returned by the module after
sending a message using output words 6 through 27
3 .
6.3.10 Message Reply Buffer (Words 28…47)
After sending a message to the module, the response data for the message is stored in the
message response buffer
3 .
6.3.11 Reserved (Words 48…69)
Reserved for future expansion.
1 Module output words 0 through 3 for channel 0 through 3, respectively.
2 X refers to channel number 0 through 3
3 For more details refer to Chapter 7