Serial board using bitbang

[irkgreen]

I was curious if anyone has used the ioBridge with the serial board in a bit bang capacity?  What i mean is: I would like to use one channel to control or monitor 8 outputs/inputs.  I assume if I use the serial board that I can build a relatively simple circuit to accomplish this.  Perhaps it is easier to explain like this:

ioBridge channel 1 -> serial board - CIRCUIT - > 8 I/O data pins

The CIRCUIT here would convert the serial output to 8 data pins that are high or low.  Ideally they would be input or output; but just output would work in my case.

I know the easy solution is to buy 2 ioBridges and just use all 8 channels, but the above method would only use one channel and would leave me 3 other channels to play with

Seems like this could be done with an FTDI chip.  Any thoughts?

[nick]

Read my post here about using a Teensy arduino implementation: http://www.iobridge.net/forum/index.php/topic,567.msg2355.html

I think you would find that much easier, cheaper and more flexible.

Nick

[irkgreen]

Very interesting. I like the options they have too.  Breadboardable version too.

My brother is pretty good at AVR programming and he suggested i use an atmeg8 chip to take the ioBridge's digital ports (in serial mode) and use it in my project. I would need to know the protocol that the ioBridge uses to serialize the DO/DI pulses.  I don't know if that is a standard.  He suggested i use an atmega8 (small size version of the 186) so the code should be for the most part a match, as long as I use the same pins and port to read the data.  Perhaps ioBridge would share this code???

Does the teensy have a time keeper of some sort?  With the write code, could it interpret these pulses?

For a one time cost the teensy and the serial board seem perfect.  But i hope to make several of my projects for friends and the AVR solution would be about 15 bucks a pop.

[wolfgang]

I am planning to do the same thing. I ordered following serial board http://www.robot-electronics.co.uk/htm/rly08tech.htm . But  I am still on business trip, so hopefully at x-mas I will have time to try it out. I will let you know how it turns out, but it will take some time.

//Wolfgang

[irkgreen]

The documentation isn't great but it seems they are saying you can plug the Tx and Rx to the DI and DO of the ioBridge (and presumably ground).  It is 73 bucks in the States.  Pretty expensive for my project.

Cool idea though.

[nick]

That board is an output only board -- you send it a byte, it sets the eight relays to reflect that byte.  Useful I'm sure in some situations, but not what you're looking for.

I wouldn't hold my breath waiting for IOBridge to release the specifications on the interface with the serial smart board.  It seems like it would be costing them revenue and adding hassle.  The nice thing about RS232 is that it is mature.

[iobridge]

http://www.iobridge.net/wiki/smart-boards/serial-smart-board

[iobridge]

From their website:

Communication settings
The Serial mode operates over a link with a baud rate of 9600 bps (no parity, 1 stop bit) and 5v signals,  The RLY08 can be found at a factory default address of 1, although this is easily changed to another of eight locations - see Changing the RLY08 Address .

From our Wiki:

The serial board operates naively on TTL voltage levels, 0v/5v. However, the RX pin will accept other voltage levels, such as 0v/3v and RS-232 levels of -10v/+10v. Be sure that the external circuit is capable of receiving 5v from the TX pin as that voltage is not adjustable.

Our serial board works native with their serial relay board.

[nick]

I wouldn't hold my breath waiting for IOBridge to release the specifications on the interface with the serial smart board.  It seems like it would be costing them revenue and adding hassle.  The nice thing about RS232 is that it is mature.

To clarify, I was responding to this comment:

My brother is pretty good at AVR programming and he suggested i use an atmeg8 chip to take the ioBridge's digital ports (in serial mode) and use it in my project. I would need to know the protocol that the ioBridge uses to serialize the DO/DI pulses.  I don't know if that is a standard.  He suggested i use an atmega8 (small size version of the 186) so the code should be for the most part a match, as long as I use the same pins and port to read the data.  Perhaps ioBridge would share this code???

[ohararp]

I have setup a very simple triac driven board that can control up to 4 amps of AC current.  There is nothing to say that this could not be increased to more ouputs or more amperage very easily.

I'll be demoing this board in Pittsburgh tomorrrow if anyone is interested.

[jason]

Ryan,

That thing looks awesome!  Add some screw terminals and it'll be ready for market.  

It's too bad I'm going to miss the show tomorrow.  Maybe Hans can patch me in via video chat.

[irkgreen]

I think I found a way to accomplish what I want but I am unable to change from inverted to true in my serial settings.  It is stuck in inverted.  Does 1200 baud only allow inverted?

[jason]

irkgreen,

Are you sure your serial board is happily connecting to the IO-204?  Is the green LED on the serial board lit?  If the options you are setting are not "sticking" that could be the reason.

[irkgreen]

I'm not using the serial board.  I am trying to analyze the digital out directly.

[irkgreen]

I have setup a very simple triac driven board that can control up to 4 amps of AC current.  There is nothing to say that this could not be increased to more ouputs or more amperage very easily.

I'll be demoing this board in Pittsburgh tomorrrow if anyone is interested.

how do you control what output is turned on?