Farnell dont stock them. eBay sellers want around 4.50 for one. What is the chip used for and can anyone advise where I can get one at a sensible price?
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These suppliers however do list them:
https://www.digikey.co.uk/product-detai ... 5-ND/38770
http://www.mouser.co.uk/Semiconductors/ ... 85&FS=True
At this point I stopped looking.
I'd have to check the schematic, but it's likely a 74HC85 would work. And it's also possible that a 74LS85 may work.
Can you tell me...
Is the Spectrum available as an option?
Can I run the H4th Rom?
Can I use a Vdrive with any of the ROMs?
Is there any central source for ZXMore/ZXMaster documents.
I am looking forward to getting this board running.
Vdrive should be possible to use in general with any ZX81 ROM when loaded/programmed at a proper location in the flash rom. I don't have experience with Vdrive personally but there shouldn't be any hardware conflict with default Vdrive IO address 7Fh. But you can use the usb flash drive (upper port of both) to load and store programs. With the current release there is a lack of subdirectory support but in further releases this will be possible, too.
Maybe try to get the board run in general first and read through the manual and experiment with it.
I have the docs already, but am a confused with the version numbers
My ROM is marked as V2.1 with a date of 07/2017 and the CPLD? has a V2.19a with a date of 08/2017. I thought/hoped that this would have sub directories.
But you say that V1.9 is the latest version?
Also the V2 construction document shows 2 diodes marked in a photo at the "Step 2 Diodes" section, but these aren't on my board. Are they a modification or been dropped?
OK, no problem re the Spectrum implementation. I'll need to look into CM/P then.
Until I get the rest of the components, its questions, questions, questions....
And the mismatch between hardware revision (CPLD) and software revision is normal as the software changes faster and more often than hardware (hopefully). But in general this is. V2 marks the CPLD for the newer board which is somehow different but will operate with the same software in future as the first V1 boards.
V2-19 is the latest hardware revision (for the V2 boards) and V2.1C the latest software revision.