Simex Simpact SZP-73, User Manual

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User manual for regulated current source SZP-73
8. THE MODBUS PRO TOCOL HANDLING
Transmission parameters: 1 start bit, 8 data bits, 1 or 2 stop bit (2 bits are send, 1 and 2 bits
are accepted when receive), no parity control
Baud rate: selectable from: 1200 to 115200 bits/second
Transmission protocol: MODBUS RTU compatible
The device parameters and display value are available via RS-485 interface, as HOLDING-
type registers (numeric values are given in U2 code) of Modbus RTU protocol. The registers
(or groups of the registers) can be read by 03h function, and wrote by 06h (single registers) or
10h (group of the registers) accordingly to Modbus RTU specification. Maximum group size for
03h and 10h functions can not exceeds 16 registers (for single frame).
The device interprets the broadcast messages, but then do not sends the answers.
8.1. LIST OF REGISTERS
Register Write Range Register description
01h 1 Yes 400 ÷ 2000 Generated current value (diect value) expressed in 0,01 mA
02h
1
Yes -999 ÷ 9999 Rescaled current value expressed according to “
OUtL ”and “ OUtH ”
06h Yes -999 ÷ 9999 “ OUtL ” parameter, no decimal point included
07h Yes -999 ÷ 9999 “ OUtH ” parameter, no decimal point included
08h Yes 0 ÷ 3
“ Pnt ” parameter: 0 - “ 0 ”; 1 - “ 0.0 ”; 2 - “ 0.00 ”; 3 - “ 0.000 ”
09h Yes 0 ÷ 1 “ Init ” parameter: 0 - UdEF option ; 1 - LASt option
0Ah Yes 400 ÷ 2000 “ IvAL ” parameter, expressed in 0,01 mA
20h 2 Yes 0 ÷ 199 Device address
21h No 2065h Device identification code (ID)
22h 3 Yes 0 ÷ 7
“bAud” parameter in “rS” menu (baud rate);
0 - 1200 baud; 1 - 2400 baud; 2 - 4800 baud; 3 - 9600 baud;
4 - 19200 baud; 5 - 38400 baud; 6 - 57600 baud; 7 - 115200 baud
23h 4 Yes 0 ÷ 1
“mbAc” parameter in “rS” menu (permission to write registers via
RS-485 interface); 0 - write denied ; 1 - write allowed
25h Yes 0 ÷ 5
“rESP” parameter in “rS” menu (additional response delay);
0 - no additional delay; 1 - ” 10c ” option; 2 - ” 20c ” option;
3 - ” 50c ” option; 4 - ” 100c ” option; 5 - ” 200c ” option;
2Dh Yes 1 ÷ 8
“
bri
” parameter (display brightness);
1
- the lowest brightness;
8
- the highest brightness
2Eh Yes 0 ÷ 1 “CoL” parameter (main colour of display): 0 - green; 1 - red
2Fh Yes 0 ÷ 1
“ Edit ” parameter (numerical parameters edit mode);
0 - „ dig ” mode; 1 - „ SLid ” mode
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