srt
Junior Member
Posts: 90
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Post by srt on Feb 10, 2023 11:07:06 GMT -5
I have I have tx sr444 issue is dsp firmwares shows qstion marks only, and no sound. changed ram chip and ROM chip re flash with a file from other member posted here. But still no sound .Any other suggestions thanks
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srt
Junior Member
Posts: 90
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Post by srt on Feb 12, 2023 8:00:55 GMT -5
Further update -dsp cs pin always shows 0volt is that the reason DSP not booting?
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Post by mastertech on Feb 16, 2023 19:09:38 GMT -5
Have you checked to see if there is any output on the DSP_CS on the MCU (Q7009)?
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srt
Junior Member
Posts: 90
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Post by srt on Feb 18, 2023 11:11:49 GMT -5
Have you checked to see if there is any output on the DSP_CS on the MCU (Q7009)? Yes on MCU side also it's near 0volt.I don't have oscilloscope to see , but in multimeter I can measure the frequency , on CS pin of microcontrollers shows 0hz.but CS pin of PCM9211 shows some freequency ,that means MCU trying to access PCM9211. MCU using same SPI bus for DSP and PCM9211.Other pin of SPI bus, DSP clock ,DSP MOSI and DSP MISO have some voltages and freequency changes also. |
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Post by mastertech on Feb 18, 2023 15:07:59 GMT -5
Yes, there can be many ic's on the same bus lines. And the chip select line is how the mcu indicates which chip on the bus it wants to communicate with.
And during startup the MCU will go through a procedure, polling each chip on the bus and looking for acknowledgement from each one. If it fails to get an answer from a chip it would likely either cease polling or continue polling the same chip. Don't know for sure as it would depend on how the firmware is written.
So you would have no idea if the DSP-CS not having any activity would be normal or not. Maybe it is not being polled for any reason. Or the firmware is stuck somewhere else on a different chip. Or polling is done and something else is causing your problem. Don't know.
I asked to check at the MCU just to be sure there were no open resistors on the CS line to the DSP.
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srt
Junior Member
Posts: 90
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Post by srt on Feb 18, 2023 22:10:53 GMT -5
Yes, there can be many ic's on the same bus lines. And the chip select line is how the mcu indicates which chip on the bus it wants to communicate with. And during startup the MCU will go through a procedure, polling each chip on the bus and looking for acknowledgement from each one. If it fails to get an answer from a chip it would likely either cease polling or continue polling the same chip. Don't know for sure as it would depend on how the firmware is written. So you would have no idea if the DSP-CS not having any activity would be normal or not. Maybe it is not being polled for any reason. Or the firmware is stuck somewhere else on a different chip. Or polling is done and something else is causing your problem. Don't know. I asked to check at the MCU just to be sure there were no open resistors on the CS line to the DSP. Yes I double checked communication line between MCU and DSP, all are ok, including DSP reset and other lines such as DSP INT and DSP ready. Also I discounted PCM9211 buslines(removed resisotors near PCM 9211) to make sure there is nothing wrong with PCM 9211), other thing is MCU resetting the DSP in every seconds also checked bus line between DSP and firmware chip, that also ok and I can see some activities going on bus line DSP and firmware chip including CS pin of firmware chip.So my doubt is something wrong with CS pin of MCU. The initial problem was the receiver in protection mode, but there was nothing worng with amp section, even I reset its again going over voltage protection(approximate 0.39volt at VPROT pin of MCU. Then I resolder the diodes near MCU then it's protection activation gone .there was littile bit corrossion near the mCu on Front display communication bus resistors that also I resolder it. |
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srt
Junior Member
Posts: 90
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Post by srt on Apr 8, 2023 22:57:13 GMT -5
Any one can provide valuable suggestions as of now i found another things there is no data reading from Flash memory even i put from another working onkyo unit, Clock, CS pin and SI pin having the Digital Data but SO pin of Flash IC have no data transfer
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Post by clintbarrett on Apr 12, 2023 1:16:23 GMT -5
Check all the connections in the amplifier, making sure that all cables and wires are properly and securely connected. It is possible that some of them may have become loose or disconnected during repair.
Check all of the amplifier's settings to make sure that they are set correctly. Something may have been inadvertently changed during repair or maintenance.
If you have the opportunity, connect the amplifier to other audio sources to see if it works at all. This may help to determine if there is a problem with the unit or the connected source.
If you have experience with electronics, you might try checking other components in the amplifier, such as capacitors or resistors, to see if they are working properly.
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