Spectrum Controls 1756sc-OF8H Series A User Manual
Page 112
98
ControlLogix
™
Analog HART Modules
Figure 7.19
Tag Name
Value in Hex
Description
HART_PASS_THRU_REQ_TX[0]
00
HART channel
HART_PASS_THRU_REQ_TX[1]
01
Pass-through command designator
HART_PASS_THRU_REQ_TX[2]
82
Start charcter
HART_PASS_THRU_REQ_TX[3]
BE
Long address byte 0
HART_PASS_THRU_REQ_TX[4]
02
Long address byte 1
HART_PASS_THRU_REQ_TX[5]
0C
Long address byte 2
HART_PASS_THRU_REQ_TX[6]
77
Long address byte 3
HART_PASS_THRU_REQ_TX[7]
37
Long address byte 4
HART_PASS_THRU_REQ_TX[8]
23
HART command = 35 decimal
HART_PASS_THRU_REQ_TX[9]
09
Byte count
HART_PASS_THRU_REQ_TX[10]
20
Range units code = 32 decimal
HART_PASS_THRU_REQ_TX[11]
44
HART_PASS_THRU_REQ_TX[12]
16
HART_PASS_THRU_REQ_TX[13]
00
HART_PASS_THRU_REQ_TX[14]
00
HART_PASS_THRU_REQ_TX[15]
C3
HART_PASS_THRU_REQ_TX[16]
16
HART_PASS_THRU_REQ_TX[17]
00
HART_PASS_THRU_REQ_TX[18]
00
HART_PASS_THRU_REQ_TX[19]
FF
Checksum
Upper Range value (This is a
floating point value = 600.0) Note:
The bytes are in reverse order.
Low er Range value (This is a
floating point value = -150.0) Note:
The bytes are in reverse order.
The HART message string, shown in figure 19, performs HART
command 35 (write range values). Once the tags are populated with the
HART message, the message can be sent using the ladder in figure 7.
The reply for the HART command will be found in the (If8h0 or
Of8ho)PassThruQryRX tag. The response message should look like the
table shown below.
Figure 7.20
Tag Name
Value in Hex
Description
HART_PASS_THRU_QRY_RX[0]
00
HART channel
HART_PASS_THRU_QRY_RX[1]
01
Pass-through command designator
HART_PASS_THRU_QRY_RX[2]
15
Length of handle + HART response
data
HART_PASS_THRU_QRY_RX[3]
02
Message handle
HART_PASS_THRU_QRY_RX[4]
86
Start charcter
HART_PASS_THRU_QRY_RX[5]
BE
Long address byte 0
HART_PASS_THRU_QRY_RX[6]
02
Long address byte 1
HART_PASS_THRU_QRY_RX[7]
0C
Long address byte 2
HART_PASS_THRU_QRY_RX[8]
77
Long address byte 3
HART_PASS_THRU_QRY_RX[9]
37
Long address byte 4
HART_PASS_THRU_QRY_RX[10]
23
HART command = 35 decimal
HART_PASS_THRU_QRY_RX[11]
0B
Byte count = 11 decimal
HART_PASS_THRU_QRY_RX[12]
00
Status Byte 0
HART_PASS_THRU_QRY_RX[13]
00
Status Byte 1
HART_PASS_THRU_QRY_RX[14]
20
Range units code = 32 decimal
HART_PASS_THRU_QRY_RX[15]
44
HART_PASS_THRU_QRY_RX[16]
16
HART_PASS_THRU_QRY_RX[17]
00
HART_PASS_THRU_QRY_RX[18]
00
HART_PASS_THRU_QRY_RX[19]
C3
HART_PASS_THRU_QRY_RX[20]
16
HART_PASS_THRU_QRY_RX[21]
00
HART_PASS_THRU_QRY_RX[22]
00
HART_PASS_THRU_QRY_RX[23]
F9
Checksum
Upper Range value (This is a
floating point value = 600) Note: The
bytes are in reverse order.
Low er Range value (This is a
floating point value = -150) Note:
The bytes are in reverse order.