Woodward 2301D, Инструкция по установке и эксплуатации, Страница: 109 / 130

Manual 26247 2301D/2301D-EC Digital Control
Woodward 101
Modbus Function Codes
Code Definition Reference Address
01 Read Digital Outputs 0XXXX
(Raise/Lower and Enable/Disable Commands)
02 Read Digital Inputs 1XXXX
(Status Indications / Alarms and Trips)
03 Read Analog Outputs 4XXXX
04 Read Analog Inputs 3XXXX
(Speed, Setpt, etc.)
05 Write Single Discrete Output 0XXXX
(Raise/Lower and Enable/Disable Commands)
08 Loopback Diagnostic Test N/A
(Subfunction 0 only)
15 Write Digital Outputs 0XXXX
16 Write Analog Outputs 4XXXX
Table 7-3. Modbus Function Codes
When a Modbus message is received, it is checked for any errors or invalid data.
If there is invalid data in the message, an error code is sent back to the master
and the control issues an alarm message. The error codes are defined in the
following table. The exception error status and respective error codes can be
viewed in the Service mode under Y**COM PORT (MODBUS)**.
If the control has not received a message for the configured time-out period, the
control will give and alarm with an error message, but no message is sent to the
master. This time-out is defaulted to 4 seconds and only applies to units using
both monitor and control (adjustable in Service Mode).
Port Adjustments
Before the 2301D will communicate with the master device, the communication
parameters must be verified. These values are set in Service Mode.
Parameter Port Adjustment Range
Baud Rate 110 to 38400
Data Bits 7 or 8
Stop Bits 1, 2 or 1.5
Parity NONE, ODD or EVEN
Driver RS232 or RS422
Table 7-4. Port Adjustments