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Problem with rs485-3 - Printable Version

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Problem with rs485-3 - Gijs3 - 13.02.2021

Hi all,

I have a LM5p2-KC and have a problem with the third rs485 port (rs485-3), it doesn't work. When i connect the modbus device to port rs485-2 does it works, so the modbus device en profile are OK.

I removed the genohm-scada-enocean package. But it doesn't make a difference.
Can somboddy help me whit this?

Regards Gijs

RE: Problem with rs485-3 - admin - 15.02.2021

Connect RS485-2 and RS485-3 A/B wires together and run this self test script. It will tell whether the port is working correctly or not:

port1 = serial.open('/dev/RS485-2', { duplex = 'half' })
port2 = serial.open('/dev/RS485-3', { duplex = 'half' })

str = '1234567890'
ok = true

function test(p1, p2)

  for i = 1, 100 do
    local res = p2:read(#str, 1)
    ok = ok and res == str
    if not ok then

test(port2, port1)
test(port1, port2)

alert('RS485 self test ' .. (ok and 'OK' or 'ERROR'))