Yes, Christian, serial interface in my AP is in TTL level, where I can use MAX3232 with DS9097 (or DS2480 directly as pointed out by njh) for 12v-to-3.3v conversion. Thanks for your (and njh's) useful information ... I will try out these hacks soon!
But ... before trying it on AP, I tried it on my PC if I can pull out any information, which I failed. This is precisely how my devices are connected: PC's DB9M (PC's standard 9-pin male) <---> DB9F-to-DB25M (a standard 9-pin to 25-pin converter) <---> DS9097E (Maxim's 25 pin Serial Adapter with a RJ11 port) <---> RJ11 cable <---> DS2781K (Maxim's voltage sensor). Here are some more info: 1. DS2781K package has 5 visible pins: DQ (data) and P- (GND) pins are, by default, connected to DS9097E (through RJ11); B+ and B- pins are connected to my 7.2 V battery's +ve and -ve terminals, and pin PIO is open. 2. DS9097E (a passive device) has a DB25F interface and is powered by RS232 interface. Any suggestion why am I not getting any info? ---- Christian Magnusson-2 wrote: > > BTW: isn't your serial interface in TTL levels? Then you have to get a > converter, such as MAX3232 > > http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1068 to connect the ds9097 > adapter. Otherwise the signal level will be inverted to the 1-wire > devices. > > > > The signal is inverted in terms of electrical polarity. e.g. a ttl low > will > generate a positive voltage on the RS232 TX output pin, a ttl high will > generate a negative RS232 TX. In the > <http://www.piclist.com/techref/io/serial/rs232sigs.htm> rs232 standard, a > low electrical level (-3 to -15 volts) is defined as a logic 1, or 'on' or > 'high' and is referred to as 'marking.' > > > > I guess it would be possible to add logic to read/write inverted levels in > OWFS, but that will require lots of re-writing. It's better to make sure > you > have RS232-levels on your pins. > > > > Read some more about serial-console cable at: > > http://wiki.openwrt.org/OpenWrtDocs/Hardware/Netgear/WGT634U#head-6128a64e71 > f6af2e38e2b1e0066d8b3c08d62d2a > > > > > > /Christian > > > > > > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Paul > Alfille > Sent: den 15 september 2007 07:25 > To: owfs-developers@lists.sourceforge.net > Subject: Re: [Owfs-developers] MIPS vs MIPSEL in OWFS > > > > Lets be systematic. > DS9097 or DS9097U > Any problems with permissions? (root?) > Try running with --error_level=9 --foreground and look at the starting > messages. > > Paul Alfille > > On 15 Sep 2007 01:05:34 -0000, suman sarkar <[EMAIL PROTECTED]> > wrote: > > > I tried some voltage sensing with DS2781K Maxim chip, which is connected > to > a DS9097 serial adapter through RJ11. > > I've installed all necessary software, but not been able to pull out any > information from the mounted directory (/mnt/1wire). My laptop's serial > port > is set to baud rate 9600. > > Here is what I did: > > owfs -d /dev/ttyS0 /mnt/1wire. > > This command does not give any error, and only creates a 1wire directory, > where I can see subdirectories: bus.0, settings, structure, statistics, > system, and uncached. > > Even "cat /dev/ttyS0" does not show any information on ttyS0 port. > > So, I am at a loss ... Is DS2781K a owfs supported device ... or am I > missing something? .... Any help will be helpful. > > > > > > > <http://adworks.rediff.com/cgi-bin/AdWorks/click.cgi/www.rediff.com/signatur > e-home.htm/[EMAIL PROTECTED]/1411820_1405315/1411271/1?PARTNER=3&OAS_QUERY= > null+target=new+> Error! Filename not specified. > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2005. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Owfs-developers mailing list > Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers > > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2005. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Owfs-developers mailing list > Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers > > -- View this message in context: http://www.nabble.com/Re%3A-MIPS-vs-MIPSEL-in-OWFS-tf4446090.html#a12696554 Sent from the OWFS - Dev mailing list archive at Nabble.com. ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
