Binary Record - Parker Compax3 Series Operating Instructions Manual

Communication
5.2.3.

Binary record

Basic structure:
Start code address
SZ A
The start code defines the frame type and is composed as follows:
Bit
Frame type
RdObj Read object
WrObj Write object
Rsp Answer
Ack Positive command acknowledgement
Nak Negative command acknowledgement
Request telegrams
302
The binary record with block securing is based on 5 different telegrams:
2 request telegrams which the control sends to Compax3 and
3 response telegrams which Compax3 returns to the control.
Telegram layout
Number of data bytes - 1
L
7
Frame identification
1
1
0
0
0
Bits 7, 6, 5 and 4 of the start code form the telegram identification; Bit 2 is always
"1".
Bits 3, 1 and 0 have different meanings for the request and response telegrams.
The address is only necessary for RS484.
-> Compax3
the address bit (Bit 0 = 1 ) shows if the start code is followed by an address
(only for RS485; for RS232 Bit 0 = 0)
the gateway bit (Bit 1 = 1) shows if the message is to be passed on.
(Please set Bit 1 = 0, as this function is not yet available)
the PLC bit (Bit 3 = 1 ) allows access to objects in the PLC/Pop format
U16, U32: for integer formats (see bus formats: Ix, Ux, V2)
IEEE 32Bit Floating Point: for broken formats (bus formats: E2_6, C4_3, Y2, Y4;
without scaling)
With Bit 3 = 0 the objects are transmitted in the DSP format.
DSP formats:
24 Bit = 3 Bytes: Integer INT24 or Fractional FRACT24
48 Bit = 6 Bytes: Real REAL48 (3 Byte Int, 3 Byte Fract) / Double Integer DINT48
/ Double Fractional DFRACT48
192-120114 N5 C3I22T11 June 2008
Data
D0 D1 ...
6 5 4 3
PLC
0 1 0 x
1 0 0 x
0 0 0 0
0 0 0 0
0 0 0 0
C3I22T11
block securing
D Crc(Hi) Crc(Lo)
n
2 1 0
Gateway address
1 x x
1 x x
1 0 1
1 1 0
1 1 1