Announcement

Collapse
No announcement yet.

Brand new DSATX won't start up...

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • Brand new DSATX won't start up...

    OK, I got this thing about a week ago and finally getting around to installing it. PC was working fine on an inverter + CarPC-EZ controller but it was not a great solution so I went with the DSATX after hearing lots of good things about it.

    So now it's in my case, connected, I have a big Optima battery sitting here by my desk for testing. All connections made, when I power up the ACC line, the red LED on the DSATX comes on, the system fans "pulse" for just an instant, and then nothing. The DSATX LED remains lit until I remove the ACC power and then it flashes twice and goes dark.

    If I close jumper B, go "dumb" and use the case power switch instead, the system will start up. I'm suspecting this MAY have something to do with the power switch pulsewidth (?) but I was stupid and didn't get the serial interface when I ordered the DSATX (had this crazy thought that I could just hook up to the TX and RX pins with an RS232 breakout and eliminate the awkward vertical adapter but obvously that won't work upon further examination).

    I just ordered the Acroname RS232 adapter from DigitalWW but I'd still like to get some idea what may be going on here. Oh, and just a side point, but it seems like this PSU, for all its good points, really should include the serial port out of the box... it seems like just about everyone who posts about it finds themselves in a situation where it needs to be reset or otherwise tweaked.

  • #2
    these symptoms remind me of what jeff was sayin about an inverted polarity mobo.. just make an inverted cable as described in jeffs site..or better before that check the power switch polarity of your mobo with a voltmeter

    Comment


    • #3
      either that, or it's possible that the 2 leads to the power switch header need to be switched.... one is ground & one is pulse for on.. if there reversed it'll do nothing.... as your discribing
      MY NEWEST INSTALL:modded infiniti fx with big screen

      first windows carpc install........my liquid cooled LVDS screen :D

      Comment


      • #4
        Originally posted by Nomader View Post
        these symptoms remind me of what jeff was sayin about an inverted polarity mobo.. just make an inverted cable as described in jeffs site..or better before that check the power switch polarity of your mobo with a voltmeter
        Interesting... I haven't seen anything like this on his site but I'll try to hunt it down.

        I've tried switching polarity on the DSATX's supplied cable with the same outcome. From what I can tell, my motherboard really only needs a switch to close the circuit to start it up... I frequently start it just by shorting the pins on the mobo with a screwdriver.

        Comment


        • #5
          of the 2 pins, one is usually a ground, & the other is looking for a ground pulse... of course jumping them is going to start it...

          some motherboards aparently use a positive trigger instead of a negative trigger, so one pin is + while the other is looking for + pulse.... this setup will obviously do the same thing if you short the 2 pins....

          the best thing to do is use a voltmeter to check for 5v on either pin... if you see 5v on either pin with the power supply connected(it should use the 5v standby as a trigger I would assume), then you know you have a + board, which is inverted from the normal expected -

          this is why you think your motherboard really only needs a switch to close the circuit to start it up... & can start it just by shorting the pins on the mobo with a screwdriver, but it works with ground, & rarely a +.....
          MY NEWEST INSTALL:modded infiniti fx with big screen

          first windows carpc install........my liquid cooled LVDS screen :D

          Comment


          • #6
            Originally posted by turbocad6 View Post
            of the 2 pins, one is usually a ground, & the other is looking for a ground pulse... of course jumping them is going to start it...

            some motherboards aparently use a positive trigger instead of a negative trigger, so one pin is + while the other is looking for + pulse.... this setup will obviously do the same thing if you short the 2 pins....

            the best thing to do is use a voltmeter to check for 5v on either pin... if you see 5v on either pin with the power supply connected(it should use the 5v standby as a trigger I would assume), then you know you have a + board, which is inverted from the normal expected -

            this is why you think your motherboard really only needs a switch to close the circuit to start it up... & can start it just by shorting the pins on the mobo with a screwdriver, but it works with ground, & rarely a +.....
            This is definitely what's going on here. I found +5V on one of the pins, so it's obviously a pull-up situation. I located an old relay in my bag of tricks and I think I've got it all taken care of now. Hope it's uneventful from here on out - thanks for the help! I was a little concerned about how much current the DSATX pull-to-ground pin can sink, since it will be used to trigger the relay, but testing it on a bench supply it looks like the relay doesn't ever pull more than 50 mA or so. That shouldn't smoke anything running for < 1 second.

            Comment


            • #7
              Also, this issue is a non-issue with setups like the CarPC-EZ because it actually uses a relay to close the power switch for on/off events; so whether it's pull-up or pull-down, it doesn't matter.

              this kind of stuff REALLY needs to be in the documentation though! it's a good product that could be great if it had solid docs.

              Comment


              • #8
                it has solid docs..the situation is discussed a lot on the mpegbox site.. the cable is very easy to make..you have 2 choises..either make a cable using a transistor.or use a relay..(moving parts...noise...tick-tick!?) i did the cable before buying the dsatx but i did not use it because i was wrong, my mobo was not inverted. i still have the cable.

                check
                http://www.mpegbox.net/fourms/viewtopic.php?t=24

                Comment


                • #9
                  I've never even SEEN the mpegbox forums until just now! I'm glad you said something. That might come in handy.

                  But still, something pretty major like this should be in the published user manual. So should silly things like "what the LED indicator is trying to tell you." It's a pretty stripped down manual that I'm just suggesting should be revised to reflect some of the more important knowledge gained from the experience of many forum users.

                  Comment


                  • #10
                    believe me the DSATX is the best out there at the moment. (I am not working for jeff ) but i agree .. jeff should supply both the inverted cable and the serial interface with the units...

                    I don't have the serial intrface myself i know i will need it 1 day) but it is ok for now!

                    and 1 important advice.. watch out how strong you turn P1 and P2.. they are veeery sensitive and will not turn 360 deg.. only 240 or something.. don't break those or then you will certainly need the seral interface to hard write them in the pic

                    Comment


                    • #11
                      yeah, I don't know why most power supplies (Opus has the same issues) depend on the ground for trigger instead of just close circiut like the carPC-EZ....

                      glad you got it going..., just curious, what board is it that you have with the + trigger switch? I've heard about that many times, but never came across one myself... even all of the laptop boards I've done use the negative trigger setup...
                      MY NEWEST INSTALL:modded infiniti fx with big screen

                      first windows carpc install........my liquid cooled LVDS screen :D

                      Comment


                      • #12
                        Originally posted by turbocad6 View Post
                        yeah, I don't know why most power supplies (Opus has the same issues) depend on the ground for trigger instead of just close circiut like the carPC-EZ....

                        glad you got it going..., just curious, what board is it that you have with the + trigger switch? I've heard about that many times, but never came across one myself... even all of the laptop boards I've done use the negative trigger setup...


                        The mobo is an MSI Nforce-2 miniATX board... don't recall the model number, I grabbed it off newegg a year or so ago for ultra-cheap. Solid moboard though.

                        Comment

                        Working...
                        X