SainSmart USB 4-channel relay

I need to find a way of getting my PC (Ubuntu 14.04 32-bit) to program one channel of this relay such that the relay closes for 3 seconds and then remains open for the next 27 seconds and then closes for 3 seconds and repeats this cycle for ten minutes or so.

The relay uses a FT245TR USB FIFO device and I have the Linuix drivers. I understand that some have written code to operate the relay using Python or Java, etc. What I need is something easy and hopefully with graphical interface.

Thank you,

John

Hi,

Look at: http://www.ftdichip.com/Support/Docu.../DS_FT245R.pdf for additional information.

BTW, which shield are you using? Most suppliers/vendors provide module information/drivers.

Moved: This thread is more suitable in <Linux - Embedded & Single-board computer> and has been moved accordingly to help your thread/question get the exposure it deserves.

Hello Onebuck:

Thank you for moving my request for help. but I am still as confused as ever, and I need a solution fast as I have a paper to give next week, and programming the SainSmart USB 4-channel relay is a mission critical step. No one, even Canonical (have support agreement), wants to tell me what applications softrware I need to use to make one of the four channels open and close the way I need. Apparently, if I had LabView, I would have the needed functionality. A program called KMTronic USB Timer 1.1 Beta (Windows XP) will find the board at COM112 and open and close the port, but apparently does not do anything with the channels. I am not sure why this is so difficult. I had a Mattson Instruments FT-IR back in 1986 that used AT&T UNIX, and had similar commands built into the graphical user interface.

Ok, so does this device appear as a serial port on your computer?

What have you written so far to interface with it?

From a quick look around online it looks like this is supposed to appear as a serial port and the following are supposed to activate the relays:

Communication Parameters:
 8 Data, 1 Stop, No Parity
 Baud rate : 9600

 Commands:
 FIRST channel commands:
 OFF command : FF 01 00 (HEX) or 255 1 0 (DEC)
 ON command : FF 01 01 (HEX) or 255 1 1 (DEC)

 SECOND channel commands:
 OFF command : FF 02 00 (HEX) or 255 2 0 (DEC)
 ON command : FF 02 01 (HEX) or 255 2 1 (DEC)

 THIRD channel commands:
 OFF command : FF 03 00 (HEX) or 255 3 0 (DEC)
 ON command : FF 03 01 (HEX) or 255 3 1 (DEC)

 FOURTH channel commands:
 OFF command : FF 04 00 (HEX) or 255 4 0 (DEC)
 ON command : FF 04 01 (HEX) or 255 4 1 (DEC)

So try:

You may have to change the stty accordingly, I've not really looked at it in much detail.

stty -F /dev/ttyS0 speed 9600 cs8 -cstopb 
echo -e -n "\xFF\x01\x01\x0a" > /dev/ttyS0

and see if that turns relay 1 on.

If that works then you can use a quick and dirty bash script to achieve your timings.

I've a Velleman 8 relay board that's similar and appears as a com port and I've written some nice sequencer software with a GUI that sends the relevant commands down the serial port to the board. However it's also Windows only.

You may also find this link handy, it's the "missing" documentation / samples from SainSmart: https://s3-ap-northeast-1.amazonaws....20-018-909.rar

Hi,

I found for Win7 using this FTDI D2XX Driver. Maybe that will help.
There are Rpi examples for this; http://www.raspberrypi.org/forums/vi...45516&p=500639
Hope this helps.
Have fun & enjoy!