Permission denied while connect to serialport?

Question

I'd like to connect to 3G modem using Ruby and the serialport gem.

My Ruby code:

require 'serialport'

class GSM
  sp = SerialPort.new('COM7', 9600)
  sp.read_timeout = 1500
  sp.write "AT\r\n"
  puts sp.read
end

I get this error after starting my script:

serialport.rb:25:in `create': Permission denied - \\.\COM7 (Errno::EACCES)

The IDE is run under administrator and the COM port is available from Putty and works fine. (I close Putty before running the script.)

is COM7 is a file or directory? – Sachin Singh Feb 03 '14 at 14:07 — Sachin Singh, Feb 03 '14 at 14:07
COM7 is virtual comport there my 3g modeb is connected – alexey.chumagin Feb 03 '14 at 14:18 — alexey.chumagin, Feb 03 '14 at 14:18

score 0 · Answer 1 · answered Feb 03 '14 at 16:12

0

According to the docs http://rubydoc.info/gems/serialport/SerialPort#new-class_method the port must be an integer or a full path to the device file. In your case I believe you want to replace 'COM7' with 6

answered Feb 03 '14 at 16:12

bridiver

Thank you for you answer. I've tried SerialPort.new(4, 9600) (connected device to another USB) and get same error serialport.rb:25:in `create': Permission denied - \\.\COM4 (Errno::EACCES) – alexey.chumagin Feb 04 '14 at 05:59
In previous comment should be SerialPort.new(3, 9600) – alexey.chumagin Feb 04 '14 at 10:19

1 Answers1