93
•
Appendix A - MODBUS RTU Protocol
5.
Always wait more than 0.5 sec after using Functions 06 or 16 to preset parameter(s) before transmitting
again to the same ASTAT-XT.
6.
Communication parameters 81...87 can only be read through the serial link. They can only be set (written)
manually.
7.
It is the user’s responsibility to read and check all changed parameter settings after presetting.
Example 2:
To Read Stop Parameter settings 41-43 addressed as 40-42 (Soft Stop Curve, Ramp Down Time and End Torque) of
ASTAT-XT # 96. The host computer sends the following frame:
byte 1: Serial Link No.
($60)
byte 2: Function
($03)
byte 3: Starting Address High ($00) (40)
byte 4: Starting Address Low ($28)
byte 5: No. of Registers High ($00)
byte 6: No. of Registers Low ($03)
byte 7: CRC_Low
($XX)
byte 8: CRC_High
($XX)
The ASTAT-XT Normal response:
byte 1: Serial Link No.
($60)
byte 2: Function
($03)
byte 3: Byte Count
($08)
byte 4: Data High
($00) (Soft Stop Curve = 0)
byte 5: Data Low
($00)
byte 6: Data High
($00) (Ramp Down Time = 10Sec)
byte 7: Data Low
($10)
byte 8: Data High
($00) (End Torque = 0)
byte 9: Data Low
($00)
byte 10: CRC_Low
($XX)
byte 11: CRC_High
($XX)
Example 3:
To write one parameter setting (Undervoltage FLT = 300V) to Parameter Setting # 10 (Addressed as 9) of ASTAT-XT #
5, the host computer sends the following frame:
byte 1: Serial Link No.
($05)
byte 2: Function
($06)
byte 3: Starting Address High ($00)
byte 4: Starting Address Low ($09)
(9)
byte 5: Preset Data High
($01)
(300)
byte 6: Preset Data Low
$2C)
byte 7: CRC_Low
($XX)
byte 8: CRC_High
($XX)
The ASTAT-XT Normal response is an echo of the query:
byte 1: Serial Link No.
($05)
byte 2: Function
($06)
byte 3: Starting Address High ($00)
byte 4: Starting Address Low ($09)
byte 5: Preset Data High
($01)
byte 6: Preset Data Low
($2C)
byte 7: CRC_Low
($XX)
byte 8: CRC_High
($XX)
Example 4:
To write multiple parameter settings (Undervoltage_FLT = 300V, Undervoltage_DLY = 10Sec, Overvoltage_FLT =
480V, Overvoltage DLY = 2Sec) to Parameter settings # 10-13(Addressed as 9-12) of ASTAT-XT # 128, the host
computer sends the following frame:
