Problem with rs485-3

[admin]

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:

Code:

require('serial')

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

str = '1234567890'
ok = true

function test(p1, p2)
  p1:flush()
  p2:flush()

  for i = 1, 100 do
    p1:write(str)
    local res = p2:read(#str, 1)
    ok = ok and res == str
    if not ok then
      break
    end
  end
end

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

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