Internal PAL tuner gets a sound upgrade!

[Darren King]

That's not as silly as it sounds, but not as elegant as everything all in one chip on the motherboard. Still if the end result is stereo then by all means!!!

A couple of points from the above posts:

1. There is no difference between the ASIC chips on a USA or UK motherboard as I have swapped chips on a board that although was not 100% working and it wasn't the ASIC at fault like I thought. I have brand new ASIC chips that were destined for UK TiVo's on hand. I'll repeat the procedure soon on a totally working USA board just to rule it out soon*

2. I was tracing the I2S (yes that's right it is I2S which is the sound version of the data I2C bus just in case other's were wondering if we have all been doing typos). From what I have gathered the main players involved here are the Micronas, the TiVo ASIC and the Analogue Devices audio encoder which is a microcontroller in itself and is quite possibly where our master/slave culprit is. I'll do a full trace on both a UK and USA board soon that are essentially bare so I do not miss any diversions on the bus to other weird places*

*both points have the asterisk (*) as time at present is a little limited. For anyone wondering why you are quite welcome to visit my website (link in signature) and see why!

Cheers

[zollymonsta]

... And from this day forward, he shall be known as 'Daddy King'

[Islander]

To get a US TiVo with the new Micronas chip to run the UK image?

I was wondering if this was possible and would it result in NICAM functionality.

I have made a few basic attempts but have had limited success.

Problems to date:

TiVo boots in NTSC mode and continues through GS in NTSC output as PALMOD not loaded to convert output back to PAL.
GS fails at import data stage (series fail).

I have tried to alter rc.sysinit to correct PAL / NTSC on GS but so far have been very good at creating reboot loops.

The reason for this tack is that I figure that the hardware after a Micronas and tuner change is getting closer to being a UK than a US and maybe that an insight into the I2S master / slave problem can be gained from this approach.

Any ideas??

[TimesOwn]

Have you running the NZ Thomson image?

[catdog]

This may be a wild idea.....but
Why not install a MSP 3410D on a daughter board, connect to the same conns as the mk1 stereo mod and command the new chip form the Tivo I2C bus. This would get around the I2S problem but present decoded NICAM to the inputs of the Tivo MSP chip.
I realise that this is not exactly a perfect solution but it would give the required result.
Any thoughts?

Building on this idea, I'm sure there are other ICs which could be used without having to program them for to specifically work with NICAM - briefly looking at STV8216 looks like it might do the job with its default reset settings and automatic detection, and it comes in a PDIP package which would make building a small board like the "mark 1" board much easier.
http://www.st.com/stonline/products/...re/ds/9786.pdf

[Darren King]

Looks like that could be an option, and Table 9 reset defaults show it is indeed a good candidate and in default setting can accept input from the SIF and output it on SCART1. From there you feed the audio into the Micronas as the Mark 1 stereo decoder or mono hookup does via pins 56 and 57 of the Micronas.

You know, it's a shame the STV8216 outputs it's I2S sound data in Master mode only (refer part 6 of the document) otherwise it would have been a good replacement for the Micronas and solve everyone's sound issues... If it could have been configured for Slave I2S and someone was willing to write a version of palmod for the different I2C control commands and the necessary adaptor board (it isn't a simple "drop in" pin-for pin Micronas compatible replacement) then it would be an excellent chip to use in place of the Micronas altogether as it has both SIF sound input for use from the tuner and analogue sound inputs for use from the rear A/V input(s). Close... but no cigar

[Islander]

I have been able to get through GS using the current NZ UK 2.5.5 image on a US Tivo but have now got two basic problems.

1. As the boot PROM is for a US TiVo it starts up as NTSC and remains in NTSC after GS has finished . If I try to change to PAL using TWP the Tivo goes into a reboot loop.

2. There is no live TV. I am not sure if this is related to 1 above or the channel settings . I have tried manually selecting individual channels but have had no luck. I have setup using 2121 , cable, Auckland FTA.

My questions are:

Is there a way to set the TiVo to PAL working at the start of sysinit?
Is the lack of live TV from the tuner related to NTSC or a tuner setup problem?

Any assistance greatly appreciated.

[petestrash]

I'm not familiar with 2.5.5, but there is code in 3.0 rc.sysinit which detects which hardware it is being run on. If it detects US hardware then it runs palmod.

Check the code.

When you say there is no live TV is the sceen blank or do you have the no signal detected message. from past memory when a PAL signal is input to a US TiVo in NTSC mode, you get the message screen.

HTH

Peter

[Islander]

I'm not familiar with 2.5.5, but there is code in 3.0 rc.sysinit which detects which hardware it is being run on. If it detects US hardware then it runs palmod.

Peter

Thanks for the reply.

I have tried a brief attempt at tweaking the code in rc.sysinit to con it into thinking that it should config for PAL early on in the script but this quickly failed into a reboot loop that could only be stopped by removing the drive and inserting into a PC to rectify the code.

This then led me off in an attempt to have a test for a reboot loop at the beginning of rc.sysinit and branch to a safe version of sysinit on the second reboot but my script writing is not great and has to date has been unsuccessful ( the reason for the above is to reduce the swapping of drive to pc etc as the areas of sysinit to do with PAL/NTSC are well before bash/telnet start. I also feel that this could also be useful as a prevention of reboot loops for other reasons).

I had reasoned that the no signal message was due to the TiVo being in NTSC mode and the tuner O/P being PAL.

The TiVo also starts / remains in Maintenance mode NTSC output even after successful completion of guided setup but I assume that this is also because the PAL/NTSC/GS settings are not being set correctly for this firmware/software/hardware configuration.

My next thought is to load Palmod early in the rc.sysinit script but I suspect that this will only uncover even more problemsresulting in reboot loops.

Presumably what is required is a versioin of Palmod that runs once early in the sysinit script that configures the tivo in PAL mode and the leaves the rest of the operation up to the UK 2.5.5 software. Unfortunatly this is beyond my coding abilities.

If anyone can assist with the problems in the above ramblings this woulld be much appreciated.

Thanks in advance.

[petestrash]

No help on the software side ATM, but I have one TiVo with a cheap $5-10 removable drive caddy and a spare housing in the PC I use for TiVo work. It makes running the drive between a PC and the TiVo much simpler during dev work.

Peter.