SparkFun Forums

[ebrandt]

Hi,

happy customer here, worked thru the embedded tutorials no problem.

Now I have ordered, received, assembled, and tested the RS-232 Shifter Board Kit (thru-hole), but am having some troubles...

it works fine in loopback mode, just as expected.
However, when connected in place of he MAX232 chip in the embedded tutorials example, it doesn't work. I've tried switching the tx/rx connections and have traced all the leads with a continuity meter, comparing to schematics, all seems good. I have tried connecting to two different computers with same (fail) results. The soldering job is reasonable, I have moderate experience soldering and feel its certainly a passable job. I have a working knowledge of analog circuits, I see how it is supposed to wrok and see nothing obviously wrong with my assembled kit.

Where can I turn to help with further troubleshooting of the shifter board? Is this the proper forum or is another better suited? Should I just order a 2nd one and see if it magically works better? I do not have access to an o-scope.

Thanks in advance, for a great site, easy ordering, and fun so far, just need a little directon on what to do when something doesn't work.

Thanks,
Eric.

[ebrandt]

anyone, anyone? Bueller?
TIA, Eric.

[jstanle1]

Hi --

I'm having the same problem with the similar PRT-08780 board. I am powering it with 5v from a PIC board and trying to transmit through it to a USB-serial dongle. I can see the transmit LED lit as data is generated by the PIC but nothing shows up on the PC connected to the USB dongle; an oscilloscope doesn't show any output at the RS-232 transmit or receive line.

Are these circuits compatible with USB-RS232 dongles? That's the only serial connection avaliable on my PC.

Thanks for any word on these boards.

[leon_heller]

I built something like it for myself but I used a MAX202 chip, that works very well. I'm surprised that SFE didn't do the same; it makes assembly much easier and less prone to error, and meets the RS-232 spec. Mine works with a USB-RS-232 adapter.

[jstanle1]

Turns out the PRT-08780 board I have is working fine -- I had rx and tx reversed. If I send data from my PIC to the rx port, it goes out RS Out properly. This may be the issue with the original post.