phram_1

phram_1 is a Commodore Amiga A600 extension - 8 MB of fast RAM.

Features :

• based on modern parts (CoolRunner CPLD, SDRAM)
• PCMCIA-friendly: holding reset for more than 3 seconds turns off high 4 MB
• current consumption around 110 mA
• speedup relative to stock A600: 33 % (by SysInfo)
• successfully tested with CheckMem and MemCheck 1.2 (both available on Aminet).

Sources

cpld/ - MMU design files (Xilinx ISE 14.7)

pcb/ - PCB design files (KiCAD, built 2017-11-24 revision a01d81e4b)

prod/ - JED, Gerbers and a photo of the expansion; the current PCB has some tweaks compared with the device on the photo