NSLU2 Linux wiki has an extensive list of options for 3.3V to RS232 or USB conversion: http://www.nslu2-linux.org/wiki/HowTo/AddASerialPort
Also, check out FOX console board using just a couple of transistors and diods: http://www.acmesystems.it/?id=106 Thanks, Sergey > On Mon, Apr 7, 2008 at 11:16 AM, Giles Thomas <[EMAIL PROTECTED]> > wrote: > > > > > On 02/04/2008, Rod Whitby <[EMAIL PROTECTED]> wrote: > > > > > Giles, it looks like you're really going to need a serial console to > > debug this one ... > > > > What would I look for with a serial console? I assume that would give me > > the console output and persist over a reboot, so perhaps I'm looking for > > kernel panic messages or the like? > > If so, I assume (as per < > > http://www.nslu2-linux.org/wiki/HowTo/AddASerialPort>) that I'll need to > > start doing a bit of hardware hacking to enable the internal serial port, is > > that right? > > > > > Regarding the serial port, I made my own, using a MAX3232 and bunch of > caps/resistors on the NSLU2 itself (actually by superglueing the MAX3232 > upside down and soldering the components to pins directly), then soldering > the RS232 signals directly to a cable and hot-glue the whole thing behind > the ethernet connector. I wouldn't suggest everyone do this. This is the > datasheet for the MAX3232: > > http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1068 > > What you need is a TTL-to-RS232 converter. I don't know if the > USB-to-serial adapters will work, as serial EIA232 is specified negative and > positive voltages (single-ended not differential), whereby TTL is just 3.3V > and ground. The MAX3232 has a charge pump to get the negative and positive > voltages higher than VCC. Not sure if you can use something that's > RS(EIA)422 capable. > > Googling for "TTL RS232" I saw these links: > > http://www.ecrater.com/product.php?pid=1750384 > http://www.compsys1.com/workbench/On_top_of_the_Bench/Max233_Adapter/max233_adapter.html > > Some of the prices for these things is extremely outrageous... $75-$200 > I've seen. Ridiculous. I looked on ebay for "rs232 TTL" and saw several > candidates. Just make sure the one you get will support 3.3V. The MAX232 > is 5V and MAX3232 is 3.3V (what you need). It shouldn't cost more than $15, > and that's being generous. > > Next, you'll need some way to interface this to the NSLU2 (see page you > mention above). If you're good at soldering, I'd recommend some header test > pins, 1x4, but I don't know the pin spacing (is it 0.1"? - if so someone > please update the wiki - I don't have access to my NSLU2 right now to > measure). Then you'll need to get some kind of female socket, 1x4 jacks, > soldered to wire to the board you bought. > > Let us know what stage you feel comfortable attacking this console project. > > -Rob > > -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
