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Post by splurge on Jan 25, 2008 17:07:26 GMT -5
Sucks man, sorry to hear. Since I lost my Hummer the first time around, I decided to go a different route with my PAL unit and not touch its existing kernal. I used the DTVBIOS and it works great. Of course the only problem is that i have to POKE it to get my ntsc and colors right.
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Post by expertsetup on Jan 25, 2008 18:08:57 GMT -5
Interesting, DTVBIOS sounds like it works well for you, I will have to take a look.
Thanks for the info.
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Post by spiff on Jan 25, 2008 18:36:19 GMT -5
Interesting, DTVBIOS sounds like it works well for you, I will have to take a look. Also, you can use TLR's kernalpatcher to save the kernal to a PRG, then name this INTRO and put it on the flash filesystem. I made a slightly patched version of TLR's kernalstarter in order to get the palette loaded also. So basically the original kernal loads INTRO, which is in fact the kernalstarter with the patched kernal. This is set to load something else (in my case LSMENU), so I get a DTV with a patched kernal, but avoiding re-flashing the $0000-$FFFF region.
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Post by expertsetup on Jan 26, 2008 13:56:37 GMT -5
Spiff great idea!
Looks like my Willem compatible programmer will work with the flash chip with a TSOP adapter. I should be able to blow a new kernal onto a new flash and solder it in.
I am just a bit unclear on how to reprogram the original flash with this method. More specifically I am not sure how I would access the original flash. If I boot from a soldered on preprogrammed flash then I assume I would need to copy the kernal to hi ram and bank it in. Then I would change the C/S state of each flash so the original flash could be asserted onto the bus. Then I assume I reprogram the original flash with TRL's flash.
Now this sounds to me as if it is quite possible, what do you guys think is this a good plan for recovery? I would just use a DPDT to toggle the C/S of each flash to switch them on or off the bus?
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Post by jsaily on Jan 27, 2008 15:24:47 GMT -5
I think you should replace the flash chip with a small form factor TSOP socket while you're at it. There should be enough space for that on the board. I investigated this in autumn, and found suitable sockets which clip on the flash chip to hold it in place. Then you could use the Willem programmer to burn whatever image you desire. The TSOP adapter for Willem costs more than the DTV though ;-) I bet any decent computer/electronics repair shop should have the tools to remove the flash chip, you'll need a hot air rework station with a TSOP removal head. EDIT: Found the TSOP-48 socket again, it's made by Meritec and is quite cheap. In my mind, it makes so much more sense to add a socket than piggyback another chip and fiddle with CS-lines... www.chip-service.de/product_info.php?language=en&info=p193_TSOP48%20Sockel%20Meritec.html
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Post by expertsetup on Jan 28, 2008 1:48:49 GMT -5
I think you should replace the flash chip with a small form factor TSOP socket while you're at it. There should be enough space for that on the board. I investigated this in autumn, and found suitable sockets which clip on the flash chip to hold it in place. Then you could use the Willem programmer to burn whatever image you desire. The TSOP adapter for Willem costs more than the DTV though ;-) I bet any decent computer/electronics repair shop should have the tools to remove the flash chip, you'll need a hot air rework station with a TSOP removal head. EDIT: Found the TSOP-48 socket again, it's made by Meritec and is quite cheap. In my mind, it makes so much more sense to add a socket than piggyback another chip and fiddle with CS-lines... www.chip-service.de/product_info.php?language=en&info=p193_TSOP48%20Sockel%20Meritec.htmlNow this is the approach I am going to take for this. I will be done with the fabrication of my hot air gun soon. I expect it will drop the chip right off without much fuss. THanks for the input and the great link. Soon I will give this corpse the old lightning rod treatment and spark some life in there.....Mary Shelly style Muahahahaha.
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Post by expertsetup on Feb 5, 2008 13:28:38 GMT -5
Well after looking at this problem for a while I have decided that I can't really put much cash out to fix my user error. So in a effort to keep this repair a bit more practical I have decided to use a smaller capacity flash chip. I have a SST39VF512 and afer reviewing the data sheet it looks like it is a good fit for the task. It is the same voltage and has all the address lines (no multiplexed address lines like some FWH I have in my shop)in the 32 pin PLCC package I have. Since I have sockets and perfboard for 32 pin PLCC on hand I thought I could use SST39VF512 without spending any cash. Here is a link to the data sheet. www.expertsetup.com/~brian/c64/flash/SST39VF512.pdfNow I was thinking there must be a way I can wire the 64K flash and the original so that I can boot from the SST39VF512 but still program the $E000-$FFFF portion of the original flash. Does this sound like a viable plan? I would even be happy to use the 64K flash for the system if I had to until I can afford the TSOP gear. This just seems like it should be possible with a little glue logic on a nice daugter board.
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Post by expertsetup on Feb 14, 2008 12:57:11 GMT -5
OK, So I have been thinking about this and perhaps this is the best course of action:
I will use only the first 8K of the 64K SST39VF512, which I will place a copy of the kernal into. This will allow me to only use A0-A13 on the SST39VF512.
A13, A14 & A15 from the DTV board will go to an OR gate which will toggle the SST39VF512 CE when the DTV does access to the $E000-$FFFF range. I would also have to disable the original flash whe the system is in the $E000-$FFFF range.
how does this sound as a solution?
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Post by expertsetup on Feb 15, 2008 0:03:51 GMT -5
After looking at this again, I see that the logic calls for AND not OR. It looks to me that the address lines A12-A15 are all used for accessing the $E000-$FFFF range. It looks like A15-A12 are for $F000-$FFFF and $A15-A13 are for $E000-$EFFF. With this in mind I guess I would need something like this to bank the 47BV161 out and the 39VF512 in. This should be what I need for the logic if I am on track. Now my next question is this, can I connect both of these logic circuits up in parallel with the address lines direct or will I need to buffer them or something? Also will I need to use NAND gates for this instead? Is there a single chip package I can use to do all of this at once? Any help for this hobby electronics hacker would really be appreciated, I am such a neophyte in design.
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Post by expertsetup on Feb 15, 2008 0:15:28 GMT -5
At this point I am over my head and cant really proceed any further without some oversight or guidance. Any push in the right direction is sure to gain momentum so I appreciate all the support and help I can get.
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Post by tlr on Feb 15, 2008 3:52:30 GMT -5
Wouldn't it be easier to just let the new flash be mirrored through the whole address range? You just need to have a working lowest 64Kb to make it boot, then load up flash.prg and switch to the original flash-chip.
This way you just need to hook the CS-lines to some gates controlled by a switch. If you keep the wires really short it might even work with just a toggle switch.
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Post by expertsetup on Feb 15, 2008 12:22:18 GMT -5
This way you just need to hook the CS-lines to some gates controlled by a switch. If you keep the wires really short it might even work with just a toggle switch. This sure does sound a lot easier, for some reason I keep thinking I can't bank the kernal out while the system is runing, I'm going to stop thinking that now. Well I will wire in my PLCC socket and a switch and give it a try, keep positive thoughts for me! thanks againm tlr.
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Post by tlr on Feb 15, 2008 12:25:44 GMT -5
This sure does sound a lot easier, for some reason I keep thinking I can't bank the kernal out while the system is runing, I'm going to stop thinking that now. Generally you can't, but I had to make that possible in flash.prg to allow for kernal reflashing.
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Post by jsaily on Feb 15, 2008 16:13:53 GMT -5
Well, if you can take the old flash chip out I can send you a programmed chip (AT49BV163DT) to solder in. These are programmed by Ziili with PAL DTV flash image, and should work. No guarantees though, but hey it's free and saves the hassle. Courtesy of Atmel. PM me if you're interested.
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Post by expertsetup on Feb 17, 2008 13:46:46 GMT -5
Thanks Jsaily, it might work with the 64K chip, if not I will send my address via PM. Well I have my materials out and am prepping the PLCC32 socket and perf board. I notice in the 49BV161 datasheet it has two possible A1 pins. One is listed as A1 and one as IO15/A1. text from pdf: I/O15 (A-1) I/O15 (Data Input/Output, Word Mode) A-1 (LSB Address Input, Byte Mode does this indicate that the original A1 (pin 24) is NC for 8bit address mode? I substitute pin 45 (IO15/A1) for pin 24 and all other connections are direct 1 to 1? I am just not used to dual mode chips.
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