sorry.i dont have this. foto from internet
Help with Kaiser's Highway Star repro
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1. NO BLATANT PIRACY. This includes reproducing homebrew less than 10 years old, with the exception of free software.
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1. NO BLATANT PIRACY. This includes reproducing homebrew less than 10 years old, with the exception of free software.
2. No advertising your reproductions, with the exception of free software.
3. Be nice. See RFC 1855 if you aren't sure what this means.
Re: Help with Kaiser's Highway Star repro
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krzysiobal
- Posts: 829
- Joined: Sun Jun 12, 2011 12:06 pm
- Location: Poland
Re: Help with Kaiser's Highway Star repro
I've just bought the Highway Star LH42 with hope that it is the same blob version as yours.
I attach the dump. One important thing that I ignored: if you look at the schematic, there is the part with 7474 that I considered wrongly weird, because it does nothing (I thought its Q is used, not /Q). It actually inverts the PRG-A16 line, so before burning your EPROM, either:
* swap the lower and upper 64kB of your 128kB ROM
or
* tie the PRG-A16 to 7474's pin 12, not pin 8.
BTW. Mine PCB slightly differs from yours by placement of few vias. The reason is that your PRG blob has a DIP28-mask rom pinout (pin22=PRG A16), while mine has a DIP32 jedec pinout (pin3=PRG A16)
I attach the dump. One important thing that I ignored: if you look at the schematic, there is the part with 7474 that I considered wrongly weird, because it does nothing (I thought its Q is used, not /Q). It actually inverts the PRG-A16 line, so before burning your EPROM, either:
* swap the lower and upper 64kB of your 128kB ROM
or
* tie the PRG-A16 to 7474's pin 12, not pin 8.
- inv.png (8.83 KiB) Viewed 3232 times