P-Bus Gateway Firmware PBGW2.128 Version 1.61

Calculating example
If you want to calculate the modbus register offset Y to control an I/O Module at
address A then:
for P-Bus 1: Y = 512 + A * 8
and
for P-Bus 2: Y = 2816 + A * 8
in which the registers:
Y + 0 to Y + 3 are the read registers 0 – 3 of the I/O Module at address A and
Y + 4 to Y + 7 are the write registers 0 – 3 of the I/O Module at address A.
Now, suppose you’ll want to control an I/O Module at address 7 on P-Bus 2 then:
Y = 2816 + 7 * 8 = 2872.
The read registers 0 – 3 of the I/O Module at address 7 are: 2872 – 2875 and
The write registers 0 – 3 of the I/O Module at address 7 are: 2876 – 2879.
An easy tool for calculating the modbus-addresses is available on our website:
www.persy.nl and can be found under document number: PCS018x
diagnostic functions
Detailed mapping of the diagnostic functions:
Dec. Hex. Description
0 0x00 Device Status
1 – 7 0x01 – 0x07 Not used
8 0x08 PBUS 1 Current Operating Mode
9 0x09 PBUS 1 Error Status
10 0x0A PBUS 1 Number of I/O Modules present
11 0x0B PBUS 1 Number of load units present
12 – 15 0x0C – 0x0F Not used
16 0x10 PBUS 2 Current Operating Mode
17 0x11 PBUS 2 Error Status
18 0x12 PBUS 2 Number of I/O Modules present
19 0x13 PBUS 2 Number of load units present
20 – 255 0x14 – 0xFF Not used
Device Status:
0 = normal operations
1 = firmware upgrade mode
2 = reset
3 = hardware failure, gateway need to be reset or exchanged
PBUS Current Operating Mode:
0 = not used
1 = slave
2 = master
PBUS Error Status:
Bit Description
0 Set = general failure, gateway need to be reset or exchanged
1 Set = overload
2..15 not used
16/17
Persy Control Services B.V.
Netherlands
PBGW2.128 – P-bus Gateway
PCS0113en
02.2009