Spectrum Controls 1769sc-HART Modules - Manual (Page 114)

Compact IO™ Isolated HART Analog Input Module
User's Manual 0300215-03 Rev. A
7-46
Table 7-20
Tag Name Val ue in Hex Descr ipti on
HART_PASS_THRU_REQ _TX[0] 00 HART channel
HART_PASS_THRU_REQ _TX[1] 01 Pass-t hrough command des ignator
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 unit s 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 Check sum
Upper Range value (This is a floating
point value = 600.0) Note: The byt es
are in reverse order.
Lower Range value (This is a floating
point value = -150.0) Note: The bytes
are in reverse order.
The HART message string, shown in Table 7-20, 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 7-10. The reply for the HART command will be found in
the If4ih0PassThruQryRX tag. The response message should look like the table shown
below.
Table 7-21
Tag Name Value in Hex Descri ption
HART_PASS_THRU_QRY_RX[0] 00 HART channel
HART_PASS_THRU_QRY_RX[1] 00 Command St atus
HART_PASS_THRU_QRY_RX[2]
15
Length of handle + HART response
dat a (Byt e 1)
HART_PASS_THRU_QRY_RX[3]
0
Length of handle + HART response
dat a (Byt e 2)
HART_PASS_THRU_QRY_RX[4] 02 Mes sage handle
HART_PASS_THRU_QRY_RX[5] 86 Start charct er
HART_PASS_THRU_QRY_RX[6] BE Long address byte 0
HART_PASS_THRU_QRY_RX[7] 02 Long address byte 1
HART_PASS_THRU_QRY_RX[8] 0C Long address byte 2
HART_PASS_THRU_QRY_RX[9] 77 Long address byte 3
HART_PASS_THRU_QRY_RX[10] 37 Long address byte 4
HART_PASS_THRU_QRY_RX[11] 23 HART command = 35 decimal
HART_PASS_THRU_QRY_RX[12] 0B Byte count = 11 decimal
HART_PASS_THRU_QRY_RX[13] 00 Status Byte 0
HART_PASS_THRU_QRY_RX[14] 00 Status Byte 1
HART_PASS_THRU_QRY_RX[15] 20 Range units code = 32 decimal
HART_PASS_THRU_QRY_RX[16] 44
HART_PASS_THRU_QRY_RX[17] 16
HART_PASS_THRU_QRY_RX[18] 00
HART_PASS_THRU_QRY_RX[19] 00
HART_PASS_THRU_QRY_RX[20] C3
HART_PASS_THRU_QRY_RX[21] 16
HART_PASS_THRU_QRY_RX[22] 00
HART_PASS_THRU_QRY_RX[23] 00
HART_PASS_THRU_QRY_RX[24] F9 Checksum
Upper Range value (This is a floating
point value = 600) Note: The bytes are
in reverse order.
Lower Range value (This is a float ing
point value = -150) Note: The bytes
are in reverse order.