Ordered the same as you have.
5PCS HN27C4096HCC-85 PLCC-44, erasable.
If I get everything else before it arrives, still have several OTP ROMS if I get impatient.
The UV eraser arrived yesterday.
XGecu TL866II Plus Programmer will be here next week. Went full tilt and purchased the package with enough adapters to rewire the house.
ROM's, at least in my Falcon Diagnostic cart are 256k each, and that's how the board is jumpered. Photo in above post.
Something I've learned in all this, is there are 64k areas times x for the various sizes. I'm not educated with electronics, only OJT and owning an Atari of one sort of another for 35 years
I,E, for a 256K ROM, thought it was just that, not divided up. Wasn't something I understood. I'd thought I could program HI/LO ROM regardless of either size, up to the addressable space of the cart port. Thank you all.
Don't know yet the size of the Falcon Diagnostic image, or the EmuTOS file size you used for development.
Will surely be pinging you soon for the EmuTos image
Think copying the diagnostic ROM, and TOS ROM would be good places to start to learn the device.
Only reason I'm using the diagnostic now is to boot the Falcon into 25MHz (opposed to the COMBEL 16MHz output), getting around the Blitter. Mainly looking at the diagnostic timing results, how setting the COMBL output at "half speed" with the diagnostic, screen artifacts, any indicators the board isn't functioning at 25MHz bus. Poor man's logic analizer
Know it's been well thought-out years before with Nemesis/Phantom and many other speeders. It's just they rely on switching the clock after TOS is booted. Trying to get away from their design, and the additional fly wires it requires.
I'm looking at possibly using the IKB/MIDI ASCI pin 5's to control a switching logic for a single oscillator.
I've socketed those two now, and discovered alternate ways of injecting a 500KHz clock to them without uplifting pins for fly wires.
Through process of elemanation using the diagnostic cart, have discovered the lowest clock the Falcon will boot at. She happily boots with a 25MHz oscillator, which will be a 1/2 clock for 2x distribution purpose on the Afterburner.
The entire cartridge port use though now may not be necessary, at least for full EmuTOS/MagiC images. I'd purchased the Vulture ST RAM board. The sdram on Lotharek's card are mounted on the top, leaving plenty of room for a ROM extender cable/card to programming adapter such as you set up, or the ROM to cartridge port mod you ingeniously came up with.
Such is the life without CLPD
Did purchase a pair of 50/50 PGA 030/882 for when your design is fully available to build
I'd given away the last set with a new PAK/FRAK/Pulpa I'd given to a user in the hopes it would help the broader Atari community. I don't think he ever got it working, coming to the conclusion his Mega was at fault from the beginning of working with his original PAK.
I "guess" that was help, kind of hoped for more out of it. Was quite the investment...