What is it?

OpenAmiga600FastRamExpansion is an Open Hardware 4 MB Fast RAM Expansion for the Commodore Amiga 600 Computer.

Why did you make it?

Most low-end Amiga models only came with Chip RAM. "Big Box" models allowed for a different type of memory to be installed, known as Fast RAM, where fast means that it's dedicated to the main processor, so that it doesn't have to compete with the other chips in order to gain access to it.

OpenAmiga600FastRamExpansion will allow you to add 4 MB of Fast RAM to your Amiga 600. This way you will be able to run more applications at once and more quickly. If you combine it with a chip RAM expansion, you will also be able to run almost all games supported by WHDLoad, pushing the smallest of the Amigas to its limits. The Fast RAM will be mapped to $200000-$5fffff, which means it will not interfere with the PCMCIA address space.

Note that the A600 was not originally designed to support a Fast RAM expansion, which means Commodore didn't provide any connector for it. Thus the only way to install it is to clip it over the CPU, using a PLCC socket placed upside-down. PLCC sockets are not meant to be used this way, so this is really a bit of a hack and might not even work in all cases.

OpenAmiga600FastRamExpansion has a counterpart for the Amiga 500, which supports up to 8 MB.

What makes it special?

OpenAmiga600FastRamExpansion is Open Hardware licensed under the CERN OHL v. 1.2.

The Documentation Location of the original project is https://github.com/SukkoPera/OpenAmiga600FastRamExpansion/.

What's included?

If you buy the component kit, this is what you will get:

• 1xATF1502AS-10JU44 CPLD
• 1xPLCC44 Socket
• 1x10-Pin IDC Male Connector
• 3x10k 0805 Resistor
• 12x100nF 0805 Capacitor
• 2x74LS157 Multiplexer
• 1xPLCC68 Socket

The Led Kit includes:

• 1x0805 Led
• 1x0805 Resistor

The CPLD must be programmed with the firmware files available on the project page. This requires a programmer, if you do not want to take care of this yourself, be sure to select the option to have it done for you.

Note that I do not provide the actual RAM chips! You will have to find your own! Compatible chips should be all 42-pin EDO RAM chips in the SOJ package, which are commonly found on old SIMM memory modules used on PCs in the late '90s-early '00s. These can be found quite easily on eBay or hopefully in your attic. Count the pins carefully, because there are also 40-pin chips around, which are NOT compatible with this expansion.

All critical components come from a Reputable Source (capitalization is not casual). Note that the final, soldered, ready-to-use product is NOT on sale. These are DIY kits which require soldering. They are not suitable for the faint-hearted, since they require soldering a lot of surface-mount components (0805 and SOJ packages).

Disclaimer

OpenAmiga600FastRamExpansion is provided to you 'as is' and without any express or implied warranties whatsoever with respect to its functionality, operability or use, including, without limitation, any implied warranties of merchantability, fitness for a particular purpose or infringement. We expressly disclaim any liability whatsoever for any direct, indirect, consequential, incidental or special damages, including, without limitation, lost revenues, lost profits, losses resulting from business interruption or loss of data, regardless of the form of action or legal theory under which the liability may be asserted, even if advised of the possibility or likelihood of such damages.

Get Help

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