Re: [Gumstix-users] controlling DTR and RTS on console-vx

[David M. <dm...@so...>]

Thanks, Dave. I've been a software geek too long; I should've checked  
the schematics.

I think I'll dig out the soldering iron and see about tying the pins  
to the correct voltages. I found some hints on how to go about doing  
this in another forum...

- David M.

> Message: 2
> Date: Tue, 7 Apr 2009 19:44:46 -0700
> From: Dave Hylands <dhy...@gm...>
> Subject: Re: [Gumstix-users] controlling DTR and RTS on console-vx
> To: "General mailing list for gumstix users."
> 	<gum...@li...>
> Message-ID:
> 	<c32...@ma...>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Hi David,
>
>> I have connected my gumstix with console-vx to a power monitoring
>> device via its serial connector. The device requires that DTR be
>> driven high and RTS low, as it's using opto-isolators and needs its
>> power to be supplied via these pins. I have written a simple C  
>> program
>> that *should* be able to do this, but it doesn't work; the pins don't
>> get driven to the correct voltages, and so no data is received. I've
>> tried both the BTUART and STUART serial ports on the console-vx, and
>> my multimeter does not show any voltage changes on those pins. If I
>> connect the STUART via a USB adapter to my computer, I can  
>> communicate
>> with it, so the port isn't defective. Does anyone have any  
>> suggestions
>> on how to solve this problem or where to look for solutions?
>
> If you examine the schematics for the console-vx, you'll see that only
> the BTUART has any signals besides Tx and Rx. And the BTUART only has
> RTS and CTS, no DTR or DSR.
>
> There was somebody else trying to manipulate BTRTS and BTCTS, but I
> don't recall the outcome. You need to ensure that the pins are muxed
> properly.
>
> If you want full modem control signals, then your best bet is to use a
> USB-to-serial adapter and plug it in to the verdex USB port.
>
> -- 
> Dave Hylands
> Shuswap, BC, Canada
> http://www.DaveHylands.com/