Onkyo TX SR875 hdmi"no signal"fault,possible DIY THX I2C/DSD project if not fixable!

[paulflan]

Onkyo TX SR875 hdmi"no signal"fault,possible DIY THX I2C/DSD project if not fixable!

Help hdmi "no signal" on Onkyo tx sr875
can anyone be so kind as to help me please,

i have an Onkyo TX SR875
its having the problem of non of the HDMI inputs/output working, just saying there is "no signal"

now iv been reading everything i can find using google till my eyes have started to hurt an developing a headache after reading through 10'000+ post's lol iv tryed changing most of the 100uf cap's just in case,

now is there any thing at all i can do/try please to get a digital audio signal into this amp higher than standard SPdif as well as possibly input DSD audio please mainly from a PC/ small SBC like raspberry pi or beagle bone black please but would be nice from also the likes of, say a blu ray player mainly for dolby trueHD an other audio formats that only work through the HDMI input's but could play such media from HTPC if only i could get something woking, like USB to I2S/I2c or other I2S audio source hardware hacked onto the right input busses on the HDMI board of the sr875 if it's even possible and can't be fixed to work normally as it should ?

the amp is a UK model with firmware,
Main, 87 1.07/08223A
DSP1 SR8051 08214A
DSP2 SR8052 07518A
DSP3 SR8053 07820B
HDMI 1.01/07706A
Video blank screen! (is this normal for this to be blank pls?)

now i tryed to find newest firmware updates an can't find a working link to download it plus cant find a .pdf file that had info about a particular capacitor but couldnt find it to download that to look into it or try it if it is related,

please any help what so ever would be nice,
help to fix this problem would be priceless

ps, if its un-fixable has anyone tryed any hardware hacks or DIY project's around this unit please ? like finding the I2C control bus as well as I2S and DSD audio stream data busses on the HDMI board and injected any audio successfully from say a Raspberry Pi or Beagle Bone Black (as it's claimed to play native DSD to a compatible DAC) or USB to I2S or anything else please ? as the rest of this unit works fine, just the hdmi in/output's

thank you for any help/reply's and taking the time to read my first post here on the forum

plus thinking about doing a cheap DIY amp kit but where's best/cheapest place in UK to get board ect rom pls ?
Thanks
Paul

 

[paulflan]

so nearly the perfect project as hdmi board is basically useless but a 10pin connection carry's standard McASP I2S multi channel audio stream from the useless hdmi board to the 3 THX DSP's an then DAC's


anyone willing to help or have any advise pls ?

as u can buy hdmi to i2c and usb to i2c boards plus others would anyone with a Onkyo TX SR875 with dead hdmi board also like to know how i get on and document my progress to make a new thread if i successfully get it working so othere's may also mod there SR875s as i think it would work nicely with a dsd capable usb to i2s with McASP
anyone tryed anything along these lines with any digital amp with internal i2s stream pls

i have a raspberry pi with i2s so first going to experiment using that as a starting point

any chance of the new'est fimware if there is 1 for uk pls, DSP firmwire would be nice

thanks

 

[paulflan]

right iv got as far as, there's what seem's to an I2c bus between main M32C/87 MCU and the v850es video mcu and another from the v850 to the sil9135 an putting my usb logic analyzer on one from v850es is dead, just pulled high as per the i2c spec but the bus from the main mcu dose show data for addresses 0x60 and 0x68 which are the correct address's for the sil9135 and thanks to chinese search engine ????????? iv found SiI9135 Programming Reference .pdf guid but can only view online and can't find a downloadable copy but O-well better than nothing, least i can read an right down what ever info i really need, mainly the I2c registers i need to set correctly ect.

now could i possibly try to program something like any of the atmel's like the arduino chip to reply to the correct address's taking the place of the sil9135 setting the appropriate register's as per the sil9135 Programmers Reference guide, as if the register's all would be set to after a succesful hdmi handshake and so correctly outputting both video signals to rest of the hdmi board and the I2S audio Stream directly from the Sil9135 to the DSP board ?
as fare as i can tell after setting the video based registers to static value's indicating all is working it's probably a good idea to use the register or an active incoming signal for when there's no audio input from chosen interface plus there's also 4 register's that change to point out, number of incoming audio channel's, bit depth and sample rate and if the incoming digital audio stream is PCM or DSD !, so is it possible to also pogram the atmel mcu to, A, use a system such as(or any ideas pls?) gpoi on the atmel as input's and use them to indicate the correct state of the incoming I2S data stream setting the correct register's to correctly reflect the incoming audio data stream, stating the correct number of incoming I2S channel pair's and bit depth/sample rate and if the digital audio stram is PCM or DSD by pulling different gpio pin's to ground ?
such as pulling 1 of 4 pin's low to indicate number of I2S channels being inputted and 2 for 16bit or 24bit and another 2 for choosing between inputting PCM or DSD audio data streams plus othere's for indicating different sample rates of the incoming I2S audio as first need the cheapest way possible that i can find to first get it working as a proof of concept before moving on to design the final setup,
so could i possibly work something out that work's with any of the USB to I2S (DSD if possible as would be nice to also check dsd function) but it also need's to have a programmable I2C bus that can do 1 o 2 things, 1. i can fully program to interface directly with the main systems I2c bus. 2. if it can only be used for basic functions then be used to interface with a fully programmed atmel to control the systems I2c register's accordingly,
if anyone has any ideas of where to even start with such an implementation please help (possibly a final XMOS chip design as they are fully programmable and also capable of 8ch I2s and also 6ch DSD audio needed but first i need the cheapest way possible to first get it working as a proof of concept so please, any help and advice
or are there any small single board linux computer's out there with 8 channel I2S and possibly also 6 channel DSD would be nice but not a deal braker i could hopefully program a I2c bus to correctly trick the main mcu into thinking the I2S audio stream is coming from the sil9135

any help or advice what so ever would be gratefully received please

has anyone what so ever tryed anything even remotely like this with a HDMI chipset and I2c bus or even anything else with the I2c bus even remotely like what im hoping of doing please and programming an atmel or whatever to trick another mcu like chip into thinking its talking to another ic chip on the I2c bus when its really talking to the progammed atmel for whatever purpose and modification's you are making please leave a comment/advice and add a link to any helpful project's if possible, anything at all please

thanks