Rs485 address <msd>, <lsd, Rs485 transmission rate <rate, By means of two rotary switches – INFICON PSG55x ATM to Medium Vacuum Gauge (RS232C / RS485C) User Manual
Page 3: Example: node address = 7d, The data link layer uses the following terminology
tira59e1 (2010-07) RS232C.cp
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The node address is an unambiguous device address in the RS485 network. The
gauge can only communicate with the network if the node address setting is
correct. Valid address range: 0 … 255 in decimal form.
The node address setting is made on the gauge in hexadecimal form (00 … FF
hex
)
by means of two rotary switches.
4
2
6
0
8
E
A
C
LSD
MSD
ADDRESS
4
2
6
0
8
E
A
C
<MSD>: upper half byte setting
<LSD>: lower half byte setting
Factory setting: 00
hex
.
Example: Node address = 7D
hex
:
MSD
8
6
LSD
E
C
When the gauge is put into operation, the firmware queries its node address.
If the node address is modified during operation it is taken over immediately.
The transmission rate is set with the rotary switch <RATE>.
Position Baud
1 9600
2 19200
3 38400
4 57600
0 reserved
5 … F
reserved
If the transmission rate is modified during operation, a reset occurs and the new
transmission rate is taken over.
Request (Req)
Confirmation (Cf)
Master
PCG5xx
Indication (Ind)
Response (Rs)
The Data Link Layer uses the following terminology:
A request is an instruction (to read/or write) transmitted by the Master.
An indication means that the Slave (gauge) recognizes a request from the Master.
A response is an answer from the Slave to the Master.
A confirmation is an acknowledgement of the response by the Master.
RS485 address
<MSD>, <LSD>
A
E
6
2
LSD
MSD
ADDRESS
RATE
SP1
SP2
ST
DIA
BUS
ADJ
3 2 1 ON
A
E
6
2
A
E
6
2
RS485 transmission rate
<RATE>
LSD
MSD
ADDRESS
RATE
SP1
SP2
ST
DIA
BUS
ADJ
3 2 1 ON
A
E
6
2
A
E
6
2
A
E
6
2
Data Link Layer
request (Req)
indication (Ind)
response (Rs)
confirmation (Cf)