I have a few more questions about the vision box.
I have read Mick's How to guide and am just waiting on my chip and programmer to come and i will get down and dirty so to speak.
In Micks guide he says to connect the reset wire to a pin near the USB chip now on the image in the wiki and in micks guide there is the USB chip whereas in my box there are a few compnents that seem to have been omited at build i have attatched both photos for comparison. Bottom right of the large image.
(http://www.t-hack.com/wiki/images/5/52/100_1155.JPG) If those chips are missing does this mean i will need to find another place to connect the reset wire.
From the looks of that image, they have ommited the USB driver chip completely :S
Maybe they are not planning to use USB in the future?
What is the model number of the box?
The reset wire MAY still work, as its a reset FROM the smp chip, so you may still be ok.
Mick
Its the DIT7421/05 box. i hope the modchip will work well with it so i can start modding the software soonish.
ahh i think mick has one of these. Going by the results of other boxes id very much expect the bootloader to have altered somewhat.
Need to get it dumped 1st and then see if its changed.
there could be an issue with dumping the bootloader, as my modding kit is quite limited as i only have a laptop and no serial interface.
i was kindof hopeing that i could use micks code for the modchip and then tweak the software on the hdd from there on.
I'm going to be helping warrmr with the electronics of this mod, just wondering if you guys would need me to dump the memory to mod this model? I'm not entirely sure how, but if you walk me through it I should have the equipment necessary. Got several Atmega chips and an AVR Dragon which has a JTAG interface, can't find a pinout of the JTAG header on the board to check if it's using a standard one or not though.
Looks identical, bridge the jumper to enable jtag on cpu, then attach wires to jtag pins on jtag header.
Instead of connecting to the atmega, connect to the parallel port lead and run the pc prog to dump the decrypted bootloader from ram.
it MAY be the same as the normal BTV bootlaoder and it MAY have been updated, unknown without trying.
You also MAY be lucky and its the same so a normal atmega chip works nps.
Info is all in wiki btw ;)
Im sorry you going to have to excuse me as i am a compleate noob.
i have this page on the Wiki http://www.t-hack.com/wiki/index.php/Dump_X300T_Bootloader which explains what i need to do.
is there a bootloader that i can compair mine to to see if its the same.
and what are teh schematics for this parallell cable.
and will Dark Neo be able to use the JTAG function on his AVR Dragon or will we need to use the parallel cable
Im assuming this may help identify the version.
TV2 Client Version 1.2.14642.551 (RELEASE)
TV2 BootRom Version 1.1527
Bootstrap http://sg01clgv.nevis.btopenworld.com/bootstrap/bootstrap.asmx
bootstrap IP 213.123.20.11
right page on wiki, wrong info on version. the version you showed is for the tv2client ie the software which runs via the hd
the page you want is this http://www.t-hack.com/wiki/index.php/EJTAG either the normal or wiggle are fine (your jtag may be a wiggle clone i dont know) but you can build the basic one omitting the resistors :D
Hmmm, is the full modchip schematic here: http://www.t-hack.com/forum/index.php?topic=47.msg1170#msg1170 capable of passing through the JTAG interface via the serial converter? I'm looking through the modchip code now, and although it uses JTAG commands it doesn't seem to allow any sort of passthrough :(
The parallel interface is a last resort, since I don't have an easily accessible port, and it's noted on the wiki that the lead length can be a problem.
Do you guys have an IRC channel set up btw?
I smell confusion.
you have to differenciate between the operation of the modchip and the programming of the modchip.
you can program the atmel either with serial or parallel or JTAG interface... you can use whatever you have.
when the modchip is in operation, it works as JTAG client and applies the memory patching via JTAG.
there is no "passthrough" because it is not needed.
if you want to dump the flashrom, you need to access the SMP863x JTAG interface from the PC, but in this case you have to remove
the modchip.
again, you can use whatever JTAG cable you have to do this, but you also need a software that supports MIPS CPUs.
the dump tool that we supply here only works with the cables shown in the WIKI.
Oh I'm certainly confused lol, but I think in this case you just misinterpreted what I was saying. I know about programming the modchip, I'm going to use the ISP header of the modchip board for that since that's how I usually program Atmel chips.
I know the modchip operates as a JTAG client for patching memory when in normal operation, the "passthrough" I was on about was only for dumping the memory, since I don't have the parts to make a wiggler cable, and I can't really get the vision box close enough to my PCs parallel port to connect it using the basic cable.
Is the source code for the dump tool available? Maybe I can program the chip to dump the data itself over serial...
I've ported the c#-dumper to c to be able to use it on my linux box, this should get you started.
ahh i think mick has one of these. Going by the results of other boxes id very much expect the bootloader to have altered somewhat.
Need to get it dumped 1st and then see if its changed.
I have one of these but the USB chip is present on mine.
TV2 BootRom Version 1.1527
Bootloader looks to be the same version :)
Mick
Thanks mick, one last question,
in your guide is there a reason why you swapped the reset line to the one closest to the usb chip from the one in the guide. Neo is thinking that it could be quite hard to get a good solder point to the point you recommend as the tags are so small and the tip on his soldering iron is quite large.
everything is going to plan at the moment.
thankyou for all of your guidance and support.
Matt
We've hit a little snag, everything is wired up right, but we're getting 0xFF bytes for the CPUID. We've checked the connections, made sure we weren't getting them mixed up, and they're fine.
One thing we have noticed is that pin 5 of the JTAG doesn't seem to be connected to anything on the board, as the resistor packs to either side of the JTAG are missing, and there's no resistor in the area circled on the attached image. We can't find a decent image of that area anywhere else to compare what is supposed to be there though. (btw this picture was before modding, we have bridged the JTAG enable)
The resistors are present on my board.
If you want an image.. there should be one in the hardware section in my "how - to" pdf :)
Mick
The resistor in your image is covered by the cables coming from the JTAG port. Do you have a 'before' shot?
If we were to bridge the resistor on J5 would this make the jtag work or would we need to bridge the 2 lots of resistor packs each side of it.
once again thanks for your guidance and for putting up with all the noobish questions.
The resistor pack at 3332 is 10k (marked 103). (probably for pullup to 3v3 for each pin) same for pack 3331.
I would think both packs would be needed to get a correct signal.
The small resistor from pin 5 just seems to be a link. it measures < 1ohm on my meter....
Mick
The resistor packs definitely seem to be pullups. I've bridged that missing resistor, and I've now started getting zeroes instead of Fs. I've put a breadboard between the mainboard and the modchip with some 10k resistors pulling up to the 3.3V, and I'm still getting zeros for the CPUID. Any idea what could be wrong? ???
What I've tried:
I've checked the wires about a million times, using the vias near the JTAG points as test points (so I know the solder joints are alright - they're about 0.2ohm). I've checked the JTAG lines aren't shorting against each other (or to anything else). I've checked the reset line (using pin 4 of the header near the JTAG, serial output shows resets are being detected correctly when booting and soft-rebooting), and the 3.3V (coming straight from the power header), and the ground (coming from the 3 pin header next to the fan header). I've followed the chip schematic properly and tested my modchip board...all seems to be in order.
Maybe some of the other lines where the missing resistor packs go are needed to be pulled up too?
try finding an old scrap pcb? or such and removing them, and fitting them to the pcb?
Mick