Couldnt really find a section for this..
Re: Couldnt really find a section for this..
Think I might have just found the dash checksum
Any chance you can read that other dash's chip the same as you did this one?
Any chance you can read that other dash's chip the same as you did this one?
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Re: Couldnt really find a section for this..
Last time I tried there was checksums for the values, then a global one for the whole thing but you could work around it by swapping bytes, as being just a sum, not a CRC that doesnt break the sums. Can get it ballpark to what your looking for by clicking over the least significant digits then swapping.
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
Re: Couldnt really find a section for this..
Code: Select all
00000000 ff ff ff ff ff ff 00 ff ff ff ff ff ff ff d3 2c |...............,|
00000010 00 00 00 00 00 00 25 da 00 00 00 00 00 00 09 f6 |......%.........|
00000020
09^25 = 2c
2c^d3 = ff
Probably more to it, but that's definitely a checksum. There might be a CRC check against words 4-7, hard to tell with only one sample.
Does this dash use a 1250ppk VSS?
Because 0x90f6 * 1250 = 3187500
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Re: Couldnt really find a section for this..
Wow, you guys are really into it. Youve got me lost so far. Last time i checked the post i was asked for some numbers and such, went to upload some pictures then saw this.
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Re: Couldnt really find a section for this..
Yeah you get that around here, lots of keen hackers Nice work festy
Re: Couldnt really find a section for this..
So getting back to re-programming via connector CN103, it has 5 pins - are they 5v, gnd, and clock,data in/data out to the 24C44, or are they to a uart on the 8051?
I've found an old 8051 of unknown origin to use as a guinnea pig so will try to put together a rom dumping circuit at some point in the future.
I'll need 25 I/O lines to read the 8051 so a pic16f877 would probably do the job.
I've found an old 8051 of unknown origin to use as a guinnea pig so will try to put together a rom dumping circuit at some point in the future.
I'll need 25 I/O lines to read the 8051 so a pic16f877 would probably do the job.
Re: Couldnt really find a section for this..
A Willem PCB3 clone should be able to read and write the 24C44 using software version 0.97ja, select "S24H45" for the device.VL400 wrote:Both of my programmers dont support it So would need to be a pic/avr to read it like festy suggested. Would be interesting to get the MCU code out too
Or here's an ebay ICSP programmer for $20 that will do them too.
Re: Couldnt really find a section for this..
Just found the facia for this one I usually label all my parts it had 358100 on it
Re: Couldnt really find a section for this..
I'll have a look and see if I can read another one tomorrow and do some tracing
Re: Couldnt really find a section for this..
Cool I'll have a lookfesty wrote:A Willem PCB3 clone should be able to read and write the 24C44 using software version 0.97ja, select "S24H45" for the device.VL400 wrote:Both of my programmers dont support it So would need to be a pic/avr to read it like festy suggested. Would be interesting to get the MCU code out too
Or here's an ebay ICSP programmer for $20 that will do them too.