SAES SIP POWER User Manual page 30

9. Modbus PDU Communication Protocol
9.1. Implementation Notes
Application Layer
Physical Layer
The inter-frame interval has to be at least 4ms.
According to Modbus specification the power supply does not answer to read requests
directed to broadcast slave ID, ever.
The power supply answers with a illegal function exception to any commands which specify a not
implemented function.
The power supply answers with illegal data address exception to any command which addresses
invalid register(s) or try to read/write write/read-only register(s).
The power supply answers with illegal data value exception to:

any command which spans multiple registers and due to an invalid number of registers
or/and number of bytes fields control reaches an invalid or misaligned register value.

any write command which fails validation.
A single word byte order is the same of the specification: MSB first.
Multi-word word order is least-significant-word first, for instance 32bit value 0x33221100 is
encoded in two consecutive words 0x1100 0x3322.
CRC is encoded with the same byte order of the specification: LSB first.
Multiple adjacent registers can be read or written with a single command.
9.2. Registers Map
Address Word R/W Type
0x1000 1 R
0x1001 1 R
0x1002 1 R
0x1003 2 R
0x2000 2 R
0x3000 1 R
0x3001 1 R
M.HIST.0109.23 Rev.1
Modbus Application Protocol V1.1b3 (PDU)
Implemented functions:

(0x03) Read Holding Registers

(0x10) Write Multiple Registers
RS-485 EIA/TIA Standard
Name
bit-mask CARD_TYPE
unsigned integer HW_CODE
unsigned integer SW_VERSION
unsigned integer SERIAL_NUMBER
unsigned integer LIFE_TIME
unsigned integer TEMPERATURE
unsigned integer ARCING_NUMBER
USER MANUAL - SIP POWER ION PUMP CONTROLLER
Description
hardware features
hardware revision
software version
serial number
total working hours
internal temperature [K]
number of arcing events from power
supply start
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