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- #EPROM PROGRAMMER FOR C64 PROJECT HOW TO#
- #EPROM PROGRAMMER FOR C64 PROJECT GENERATOR#
- #EPROM PROGRAMMER FOR C64 PROJECT UPGRADE#
- #EPROM PROGRAMMER FOR C64 PROJECT SOFTWARE#
- #EPROM PROGRAMMER FOR C64 PROJECT CODE#
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This is where the EPROM emulator comes handy, a device that can temporary “replace” your EPROM chip, it is controlled by a computer and can be reprogrammed in seconds.
#EPROM PROGRAMMER FOR C64 PROJECT CODE#
The entire process is extremely slow and has to be repeated every time you want to make even a small one bit change! And yes, there are modern EPROM alternatives based on Flash technology, that could save you the 20-30 min erase time, but the rest of the process is still the same and still annoyingly slow if you’re writing code and trying to “debug” it. That means, remove the EPROM from its host computer, subject it to 20-30min of UV light exposure, program it with EPROM programmer, re-install in host computer.
#EPROM PROGRAMMER FOR C64 PROJECT SOFTWARE#
Imagine you are developing software (well, firmware more likely) and you need to change the “program” in your EPROM memory. By its nature, this type of memory is “read only” and to change its content you need to erase it with UV light. So, what is the issue and why would one need an EPROM emulator. See below: Example of EPROM chip used in Commodore 64 “test” cartridge. Those EPROMS typically come as ICs in DIP28 package with a “window” in the middle used to “erase” the memory using UV light. And when I say “computers” I refer to the 80s eight bit machines (Commodore, Amiga ZX Spectrum, Tandy etc.), but also other computer like devices, controllers etc. EPROM or Erasable Programmable Read- Only Memory is a type of programmable read-only memory that is used to store program in “computers”. Well, before I explain what an EPROM Emulator is, I should first explain what an EPROM is. I recently posted an article that shows how people ended up using the emulator, check it out there: EPROM emulator NG use cases. This makes it a little more difficult to deal with as you need a larger socket and there are more pins/wires to jumper.As always, all source code and design documents are on my github page: EPROM-EMU-NG on GitHub The 27010 is a 128Mb EPROM which is in a 32 pin package. This makes installing larger EPROMs easy to do as you only need to deal with switching in/out the extra address lines. The pinout differences between the 2764 to 27512 are not extensive, mainly extra address lines that need to be dealt with. In order to use a 2764 in place of one of these ROMS, an adapter socket is needed. The 2364 is an 8Kb PROM and is the same pinout as the 24-pin ROMS used in the original C, like 901227-0x (KERNAL in the C64) or 901229-0x (KERNAL in the 1541). The 23 are 2Kb ROM's but are not common on Commodore equipment.
#EPROM PROGRAMMER FOR C64 PROJECT GENERATOR#
The 2332 is a 4Kb PROM and is the same pinout at the 24-pin ROM used for the character generator in the C64. Apparently, you can use these in the older drives and it makes the drive more reliable as most of the and REL bugs are gone. Of the 1541-II ROM's are for use in an older 1541. The BINARY files are raw format images (without load addresses) and the S19 files are also provided if you want to burn them and you have an EPROM programmer that supports the S19 format.
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The ROMs below are the latest versions for the C64's and drives. When an EPROM is erased and ready to burn all the bits are set to 1 so all bytes will read as FF.
#EPROM PROGRAMMER FOR C64 PROJECT UPGRADE#
This is especially good if you've replaced the drive kernal ROM with something else and want to verify that the upgrade worked. You will receive back the drive DOS revision. From Star Commander, select F2 (User Menu), and choose user command and send a U9.
#EPROM PROGRAMMER FOR C64 PROJECT HOW TO#
I will not attempt to document how to burn an EPROM as each programmer is unique and the instructions vary greatly. To burn an EPROM requires an EPROM programmer. You can check them on the burner to see if they are indeed erased and if not, re-erase them for 1 minute increments, checking after each erasure session until they show erased.
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Typically EPROMs need about 3 minutes to erase. To erase an EPROM you will need a UV eraser. I generally go with 200-250ns as they were very common. The Commodore chip specs for the 23 PROM's show them as slow as 450ns so almost any EPROM faster than 450ns will so. The speed of the EPROM is not so critical. See here for detailed instructions on how to build one. In order to upgrade to a newer ROM revision or change the ROM to something else and use either a 2732 (for the character set) or 2764 (for kernal/DOS) EPROM, a socket adapter must be built. The ROM's in the C64 and the original 1541 models are 24 pin and are not directly pin compatible with burnable 2732 or 2764 EPROMS.