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NOTE: Address 00 is reserved for global addressing. Do not assign the global
address to any device. When commands with the global address are sent, all
devices on the RS-485 bus execute the command but do not reply with an
acknowledgement message.
The global address can be used to change RS-485 address for a particular device without local
display and joystick interface with unknown address:
1. Make sure only one device (whose address must be changed) is connected to
the RS-485 network.
2. Type the memory write command with the global address:
!00,MW,118,XX,<CR>where XX, the new hexadecimal address, can be from 01 to FF.
After the new address has been assigned, a device will accept commands with the
new address.
NOTE: Do not assign the same RS-485 address to two or more devices on the
same RS-485 bus. If two or more devices with the same address are connected
to one RS-485 network, a communication collision on the bus will result, leading
to communication errors.
Several examples of commands are shown below. All assume that the DPC controller has been
confi gured for decimal address 18 (12 hex) on the RS-485 bus:
1. To get currently selected Gas: !12,G<CR>
The DPC will reply: !12,G:0,AIR<CR>
(assuming the Current Gas is #0, calibrated for AIR)
2. To get current Flow Rate Alarm status:
!12,FA,R<CR>
The DPC will reply: !12,FAR:N<CR> (assuming no fl ow alarm conditions)
3. To get a mass and volumetric fl ow reading:
!12,F<CR>
The DPC will reply: !12,50.0,50.3<CR> (assuming the mass fl ow is at 50% FS)
4. Set the Set Point to 100.0 % full scale:
!12,SP,100.0<CR>
The DPC will reply: !12,SP:100.0<CR>
5. Set the High and Low Flow Alarm limit to 90% and 10% of Full Scale fl ow rate:
!12,FA,C,90.0,10.0<CR>
The DPC will reply: !12,90.00,10.00,<CR>
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