Spectrum Controls 1769sc-HART Modules - Manual (Page 82)

Compact IO™ Isolated HART Analog Input Module
User's Manual 0300215-03 Rev. A
7-14
Figure 7-6 Sending Message
Up to 257
Bytes
MsgMasterControl (Hex) =
RR|SS
RR = Page Last Received
SS = Page Being Sent
MsgRequestSize =
Total size of message in
bytes, up to 257 bytes.
MsgRequestBuffer =
One page of data being sent
to module. Last byte is
page checksum. 1 page =
38 bytes max.
First
Page
38 Bytes
Second
Page
nth
Page
MsgMasterControl = 00|02
MsgSlaveControl = 01|00
Bytes sent <> MsgRequestSize
Message
to be sent
Up to 257
Bytes
MsgMasterControl (Hex) =
RR|SS
RR = Page Last Received
SS = Page Being Sent
MsgRequestSize =
Total size of message in
bytes, up to 257 bytes.
MsgRequestBuffer =
One page of data being sent
to module. Last byte is
page checksum. 1 page =
38 bytes max.
First
Page
38 Bytes
Second
Page
nth
Page
MsgMasterControl = 00|02
MsgSlaveControl = 02|00
Bytes sent = MsgRequestSize
Message
to be sent
If checksum
is valid, then
ready to
receive data
from module
MsgMasterControl (Hex) =
RR|SS
RR = Page Last Received
SS = Page Being Sent
MsgRequestSize =
Total size of message in
bytes, up to 257 bytes.
MsgRequestBuffer =
One page of data being sent
to module. Last byte is
page checksum. 1 page =
38 bytes max.
First
Page
Up to 257
Bytes
38 Bytes
Second
Page
nth
Page
MsgMasterControl = 00|01
MsgSlaveControl = 00|00
Bytes sent <> MsgRequestSize
Message
to be sent