Hardware manual PCD7.LRxx-PG5 room controller │ Document 27-653; version ENG07 │ 2019-03-21
Saia-Burgess Controls AG
Communication
5
5-22
Modbus on PCD7.LRxx-P5 RS-485 interfaces
PCD7.LRxx-P5 write Modbus values to PCD 1/2/3
PCD7.LRxx-P5
PCD 1/2/3
PCD7.LRxx-P5 acting as
Modbus client and writing 16-bit
or 32-bit values to the PCD 1/2/3
Media mapping on the PCD 1/2/3 acting as Modbus server:
Example: if client writes 12 Modbus objects, where the content of the PCD register on the client is defined as
11112222 hex for PCD Reg
33334444 hex for PCD Reg +1 … as shown on the left side of the table.
PCD7.LRxx-P5
Register
Number
Example of
value stored
on the
PCD7.LRxx-P5
register
Modbus
Holding Register
Number
PCD 1/2/3
Register Number
on the PCD 1/2/3
PCD 1/2/3
Register content if
written with 16 bits
Modbus object
number = PCD
register number
PCD 1/2/3
Register content if
written with 32 bits
Modbus object
range 10001 and
higher must be
used on the PCD
1/2/3.
To access register
600, it is necessary
to access the Mod-
bus object 11201
(2 x 600 + 10001)
PCD 1/2/3
Register content if
written with 32 bits
swapped
Modbus object
range 10001 and
higher must be
used on the PCD
1/2/3.
To access register
600, it is necessary
to access the Mod-
bus object 11201
(2 x 600 + 10001)
PCD Reg
11112222
hex
HR0 / HR1
PCD Reg 0
00002222
hex
11112222
hex
22221111
hex
PCD Reg+1
33334444
hex
HR2 / HR3
PCD Reg 1
00004444
hex
33334444
hex
44443333
hex
PCD Reg+2
55556666
hex
HR4 / HR5
PCD Reg 2
00006666
hex
55556666
hex
66665555
hex
PCD Reg+3
77778888
hex
HR6 / HR7
PCD Reg 3
00008888
hex
77778888
hex
88887777
hex
PCD Reg+4
9999AAAA
hex
HR8 / HR9
PCD Reg 4
00008888
hex
9999AAAA
hex
AAAA9999
hex
PCD Reg+5
BBBBCCCC
hex
HR10 / HR11
PCD Reg 5
0000CCCC
hex
BBBBCCCC
hex
CCCCBBBB
hex
PCD Reg+6
DDDDEEEE
hex
HR12 / HR13
PCD Reg 6
0000EEEE
hex
DDDDEEEE
hex
EEEEDDDD
hex
PCD Reg+7
FFFF1111
hex
HR14 / HR15
PCD Reg 7
00001111
hex
FFFF1111
hex
1111FFFF
hex
PCD Reg+8
22223333
hex
HR16 / HR17
PCD Reg 8
00003333
hex
22223333
hex
33332222
hex
PCD Reg+9
44445555
hex
HR18 / HR19
PCD Reg 9
00005555
hex
44445555
hex
55554444
hex
PCD Reg+10
66667777
hex
HR20 / HR21
PCD Reg 10
00007777
hex
66667777
hex
77776666
hex
PCD Reg+11
88889999
hex
HR22 / HR23
PCD Reg 11
00009999
hex
88889999
hex
99998888
hex
PCD Reg+12
AAAABBBB
hex
HR24 / HR25
PCD Reg 12
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