Computer Control; Data Format - Danfoss 176F7300 Manual

1 Computer Control

• There is abuilt-in RS-485 serial interface, marked (RJ-11) on the control card. The
pins are defined below:
Each VLT MICRO drive has a pre-assigned communication address specified by
Pr.88. The computer then controls each AC drive according to its communication
address.
• The VLT micro can be setup to communicate on Modbus networks using one of the
following modes: ASCII (American Standard Code for Information Interchange).
Users can select the desired mode along with the serial port communication
protocol in Pr.92.
• Code Meaning:
ASCII mode:
Each 8-bit data is the combination of two ASCII characters. For example, a 1-byte
data: 64 Hex, shown as "64" in ASCII, consists of "6" (36Hex) and "4" (34Hex).

2 Data Format

2.1 10-bit character frame (For 7-bit character):
• (7, N, 2: Pr.92 = 0)
Start 0 1
bit
2: GND
3: SG–
4: SG+
5: +5V
6 1
2 3 4 5
7-bit character
10-bit character frame
83
VLT ® MICRO
6 Stop Stop
bit bit