Archive for May, 2009
As announced at the C4 EXPO, I am working with Mark Fellows (Highland IT Solutions) to finalize a licensing agreement for ‘JiffyDOS’ ROM Overlay manufacture and distribution. In addition to hardware ROM enhancement units, I will also offer image downloads for 1541 Ultimate, C64DTV, and emulator users, as well as an amnesty offering for unlicensed copies.
To minimize manual manufacturing processes inherent in the current EPROM-based JiffyDOS offerings, my goal is to utilize the ROM-el EEPROM/FLASH solution for JiffyDOS hardware offerings.
23128 and 23256 ROMs are not as hard to deal with, as 27XXX JEDEC standard EPROMs share the same pinout. However, some of the benefits of the 2364 ROM-el still remain, such as:
- Use of 5V programmable FLASH/EEPROM
- Can be pre-assembled and field programmed
If used in a switched ROM scenario (one where the upper address bits are toggled on or off via a switch), this design can save a lot of time (most 27256/27512 switched ROM replacement options I’ve seen manually bend the additional address pins over the top of the EPROM and hand solder a resistor to Vcc.)
Thus, I’m considering this unit as well for production. It offers some additional configuration options over the 2364 ROM-el, but retains the ease of assembly and programming of the 2364 ROM-el.
Another project of mine requires a way to replace the 2364 ROMs on Commodore computers, so I started looking for a 2764 to 2364 adapter. After designing one, I determined that DIP EPROMs are starting to get very expensive, so I set about designing a Flash version. My tentative name is ROM-el. Since Flash is considered ROM as well, the name is a bit off, but I liked it, and only the pedantic will probably care.