Hex manipulation

[Erwin van der Zwart]

Hi Buuuudzik,

Here is a script i use for other devices, here is a function to read a line without knowing the lenght, also another HEX function you might want to use:

Code:

--------------------------------------------------------------------- -- *********************** START CONNECTION ********************** -- --------------------------------------------------------------------- -- Load Modules require('serial') -- Open connection port = serial.open('/dev/RS485', { baudrate = 4800, parity = 'odd', duplex = 'half', databits = 8, stopbits = 1 }) --------------------------------------------------------------------- -- *********************** START FUNCTIONS *********************** -- --------------------------------------------------------------------- -- Function to read until carier return is received or timeout function readline(port, timeout)  local char, buf  buf = {}  while true do    char = port:read(1, timeout or 0.2)    -- error (timeout) or newline, stop    if char == nil or char == '\n' then      break    -- ignore cr char    elseif char ~= '\r' then      table.insert(buf, char)    end  end  return table.concat(buf) end -- Function to write to port and return a reply function writetoport(port, timeout, command)     -- Write data to port as HEX  port:write(command)     -- Call function to read data  line = readline(port, timeout)  if #line > 0 then      return line  else    return "No reply received"  end end -- Function to decode hex string value to readable string format function str2hex(str)     raw_len = string.len(str)     i = 1  while i <= raw_len do    current_hexvalue = '0x' .. string.format("%02x", string.byte(str, i))    if value then      value = value .. ', ' .. current_hexvalue    else        value = current_hexvalue    end    i = i + 1  end  return value end --------------------------------------------------------------------- -- ************************ END FUNCTIONS ************************ -- --------------------------------------------------------------------- --------------------------------------------------------------------- -- *********************** START WRITE/READ ********************** -- --------------------------------------------------------------------- -- Declare command to send to rotel command = string.char(0xfe, 0x03, 0xa5, 0x10, 0x0a, 0xc2) -- power toggle -- Send command to port and wait for reply or timeout reply = writetoport(port, 1, command)-- Timeout is set to 1 second (default = 0.2) --------------------------------------------------------------------- -- ************************ END WRITE/READ *********************** -- --------------------------------------------------------------------- --------------------------------------------------------------------- -- ************************ START LOGGING ************************ -- --------------------------------------------------------------------- -- Process the reply if reply == "No reply received" then  log(reply) else  --Decode the reply if hex  decoded = str2hex(reply)  log(decoded) end   --------------------------------------------------------------------- -- ************************* END LOGGING ************************* -- --------------------------------------------------------------------- -- Close port port:close() --------------------------------------------------------------------- -- ************************ END CONNECTION *********************** -- ---------------------------------------------------------------------

Hope this helps you..

BR,

Erwin