On Sun, 2010-01-10 at 21:41 -0500, Dale Pontius wrote: > Every now and then my hvr-1600 goes red-screen on me. (Apparently this > indicates no signal, so presumably something has gone south in the > front-end selection logic.) From the lookup I've done, it's a symptom of > no signal.
I wouldn't say that "red screen" means "no signal". I would say that "red screen", with buffers still being DMA'ed properly from the CX23418, means the analog front end/digitizer in the CX23418 stopped operating normally. > For a while I blamed it on my cheapo splitter/amp, because > when it happened I'd take things down, move the input to another > channel, and things would work, again. Recently I installed a much > better distribution amp. > > Today it happened again. I guess I need to sort out symptoms better, > but from what I can tell, once it goes red-screen, a simple reboot > doesn't clear things up, though I need to verify this. I'm going to > presume that rmmod/modprobe wouldn't clear things either, if a reboot > didn't. These facts are a bit murky, from the old splitter/amp, but I > do remember that once an input went, it stayed gone until I fiddled with > the hardware. > > Tonight when that happened, I realized that fiddling with the hardware > also meant really disconnecting the power, and that means the V5SB (5V > standby - on when the front-panel power is off) too. So I shutdown, > then turned off the switch on the pack of the power supply to really > power off, and waited about 20 minutes. (I wanted to record "Serenity" > and I thought it was at 6:00, but it was really at 6:30, so I could have > given it 50 minutes.) Anyway, all is well now. So it sounds like either: a. a resistor somewhere - power supply, motherboard, or HVR-1600 - has open-circuited. Once you build up enough charge on some capacitors somewhere, the circuit stops working (oscillators for clock signals stop oscillating) b. You're power supply voltages are sagging and you're getting CMOS latch up. See section 4.3 of the publicly available CX25840/1/2/3 datasheet for a terse description of CMOS latch up. Some rhetorical questions: Was 20 minutes needed to get back to normal operation, or is some smaller period of time also OK? How many minutes of continuous operation does it take to get the red screen? Is there a lot of variance in that number? > Next time it goes red-screen, I'll first shut down mythbackend, then try > the rmmod/modprobe, and if that doesn't work I'll simply reboot. Then > I'll try the full powerdown, including the backside switch. (and report > findings here) By the way, this is on the NTSC side, while in this > state the ATSC/QAM side works OK. OK. It sounds like the integrated ananlog front-end/digitizer is what is ceasing proper operation. ATSC/QAM doesn't require that piece to be operational. It could also be a DDR ram problem on the HVR-1600 board. The digitized video gets dumped into a certain memory and the encoder works on it from there. If that memory is faulty, one could also expect incorrect video (but a solid colored field is not what I would really expect). > In the meantime, have other seen this, or have any observations? A few more rhetorical questions: How old is your power supply? Is it a name brand or off brand? Regards, Andy > Dale Pontius _______________________________________________ ivtv-users mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-users
