| *** tpb has joined #timvideos | 00:00 | |
| thaytan | xfxf, that's more a question for one of the python binding guys - bilboed or thibault | 01:38 |
|---|---|---|
| thaytan | we used to have support in the old manual bindings though, I think | 01:39 |
| thaytan | so probably just requires some overrides in gst-python | 01:39 |
| thaytan | some reference to the GStreamer 0.10 python bindings might help | 01:40 |
| *** sb0 has quit IRC | 03:38 | |
| mithro | _florent_: ping me if you are around this evening | 03:45 |
| *** rohitksingh_work has joined #timvideos | 04:20 | |
| *** sb0 has joined #timvideos | 04:24 | |
| *** rohitksingh_wor1 has joined #timvideos | 04:51 | |
| *** rohitksingh_work has quit IRC | 04:52 | |
| *** rohitksingh_wor1 has quit IRC | 05:21 | |
| *** rohitksingh_work has joined #timvideos | 05:43 | |
| *** Bertl_zZ is now known as Bertl | 06:11 | |
| *** rohitksingh_wor1 has joined #timvideos | 06:39 | |
| *** rohitksingh_work has quit IRC | 06:39 | |
| *** Bertl is now known as Bertl_oO | 06:45 | |
| *** NTU has quit IRC | 07:57 | |
| *** RattusRattus has joined #timvideos | 08:02 | |
| RattusRattus | hay mithro sorry, work has gone carzey, I've not been reading IRC for weeks. | 08:03 |
| * RattusRattus needs to recap.... give me half hour or so | 08:07 | |
| mithro | RattusRattus: okay | 08:10 |
| RattusRattus | So DCC is just an I2c bus. As such the SDA signal is bi-directional, but the clock signal needs only be in one direction: however the datasheet states "Bidirectional Level-Shifting N-Channel FETs Provided for DDC_CLK and DDC_DATA Channels | 08:13 |
| RattusRattus | so yes this is suitable for both VGA IN and VGA output ports | 08:13 |
| * RattusRattus looks further and sees that the data sheet refers to the pins as In and Out. this is just a nominal name, if you look at section 7.2 you can see that they are FET level shifters and therfore bi-directional. | 08:17 | |
| RattusRattus | the important bit is the "Out" side has the ESD clamp diodes... | 08:18 |
| RattusRattus | mithro: please also note the layout guidelines on the datasheet (figure 9) | 08:21 |
| RattusRattus | (surface routin, no vias) | 08:21 |
| RattusRattus | routing even! | 08:21 |
| mithro | RattusRattus: The I2C is bidirectional | 08:26 |
| mithro | RattusRattus: the HSYNC / VSYNC signals are not | 08:26 |
| RattusRattus | doh! | 08:27 |
| *** NTU has joined #timvideos | 08:28 | |
| RattusRattus | yes - I need to add a couple of resistors to the schematic for the input ~ A simple devider will bring the signals down (1k to SYNC in, 2k to GND, mid point is 3V3 sync signal) | 08:45 |
| RattusRattus | Do not connect pins 13 or 15, but still connect 14 and 16 to give ESD protection | 08:47 |
| RattusRattus | no need for active level shift here | 08:47 |
| mithro | RattusRattus: But it looks like the drivers would cause the output always be driven to a value? | 09:19 |
| mithro | RattusRattus: the SYNC pins on the AD9948 are 5V tolerant | 09:19 |
| RattusRattus | yes I had spotted that and was looking at alternatives: options include: seporate clamp diodes (with / without resistor devider - with is probably safest), seporate clamp diodes and level shifter (but looks more expensive) | 09:26 |
| RattusRattus | ehhh hang on.... just looking again. we can connect vsysnc seporatly..... | 09:29 |
| RattusRattus | so vsync can be 3v3 for driving in reverse | 09:29 |
| RattusRattus | but we would need to add the resistors still. | 09:32 |
| mithro | RattusRattus: hrm? These VSYNC / HSYNC signals are coming from somewhere else | 09:33 |
| mithro | RattusRattus: Looking at AD9984, it seems like we can just connect them directly to it, with some ESD protection | 09:33 |
| mithro | RattusRattus: an alternative options is to replace the TPD with a PACVGA200 which does seem to separate the drivers from the ESD protection | 09:34 |
| RattusRattus | so the supply for tyhe vsync pin of the shifetr can be 3V3 (it doesn't have to be the same as VCC_video - thats why it is a seporate pin) | 09:35 |
| * RattusRattus also looks at PACVGA200 | 09:35 | |
| mithro | RattusRattus: The problem isn't the supply for the shifter - the ESD protection is only on the output side of the shifter, not the input - hence we can't just connect it backwards | 09:39 |
| RattusRattus | no I haven't been clear. Vcc_sync = 3V3, Sync_In* to Vga connector (via resistor devider), sync_out* to sync input of ADC | 09:41 |
| RattusRattus | which is pretty much the same as PACVGA200. | 09:42 |
| RattusRattus | I can change to PACVGA200 if you prefer thoughj | 09:42 |
| RattusRattus | nope no good. the TPD7S019 sync input pins don't have ESD protection.... so it should be the PACVGA200 | 09:48 |
| * RattusRattus updates schematics | 09:48 | |
| mithro | RattusRattus: so, as I mentioned above.... | 09:56 |
| mithro | The PACVGA200 is quite expensive :( | 09:57 |
| mithro | But I wasn't able to find anything else | 09:57 |
| mithro | RattusRattus: oh, I had unpushed changes to the schematic.... | 09:58 |
| RattusRattus | yes as you said above :-( sorry | 09:58 |
| mithro | RattusRattus: btw - if you say my nick it flashes a notification :) | 09:58 |
| RattusRattus | will I can price up just adding ESD diodes to sync lines and still using TPD7S019 | 09:58 |
| mithro | Well, I guess the PACVGA200 saves the term resistors - which is kind of nice | 10:10 |
| mithro | But it does seem to be double the TPD7S019 price on Digikey | 10:11 |
| *** rohitksingh_wor1 has quit IRC | 10:11 | |
| mithro | RattusRattus: http://www.findchips.com/search/pacvga200 | 10:18 |
| tpb | Title: pacvga200 Stock and Price by Distributor (at www.findchips.com) | 10:18 |
| *** rohitksingh_work has joined #timvideos | 10:26 | |
| *** rohitksingh_work has quit IRC | 10:39 | |
| *** rohitksingh_work has joined #timvideos | 10:44 | |
| RattusRattus | mithro: I guess we could use a TPD2S017 on the SYNC lines and keep the TPD7S019.... still costs less than the PACVGA200 | 11:13 |
| mithro | RattusRattus: Sure I guess? | 11:25 |
| RattusRattus | ok. /me will need to add symbol, will do this this evening when I get home | 11:26 |
| mithro | RattusRattus: okay, make sure you pull the latest changes before doing anything | 11:27 |
| RattusRattus | willco | 11:27 |
| *** rohitksingh_work has quit IRC | 12:06 | |
| *** rohitksingh_work has joined #timvideos | 12:09 | |
| *** cr1901_modern1 is now known as cr1901_modern | 12:29 | |
| *** sb0 has quit IRC | 12:31 | |
| *** sb0 has joined #timvideos | 13:09 | |
| mithro | RattusRattus: just pushed the latest update from the PCB designer to the VGA repo | 13:10 |
| *** rohitksingh_work has quit IRC | 13:16 | |
| *** rohitksingh has joined #timvideos | 14:53 | |
| *** Bertl_oO is now known as Bertl_zZ | 16:31 | |
| *** rohitksingh has quit IRC | 20:24 | |
| *** sb0 has quit IRC | 21:27 | |
| mithro | RattusRattus: any luck? | 21:48 |
Generated by irclog2html.py 2.13.1 by Marius Gedminas - find it at mg.pov.lt!