Скачать или смотреть Heathkit H8 Part 4: 16 Megabytes of RAM in a Heathkit H8 Vintage Computer

Here I make a 16 megabyte RAM board for my Heathkit H8 8-bit computer. The H8 typically shipped with 4K or 8K of RAM, and 64K was a popular upgrade, sometimes requiring multiple boards. There were a few 64K boards back in the day, but to my knowledge nobody has ever made an 8 Megabyte board! Whatever would you even use that much memory for. In this case, I build and used two 8MB boards to add a total of 16MB of memory and used this to create 8 Ramdisks of approximate size 2MB each. The board allows either AS6C4008 512KB RAM chips or 39SF040 Flash chips to be used. The RAM contents are lost at power off (unless battery backup is used). The flash chips are persistent, but much more inconvenient to write. With these boards I also demonstrate the SEBHC Z80 board, and even try the Ramdisks on the original Heathkit 2 MHz 8080 board. You can boot from the Ramdisks. You can image copy one Ramdisk to another. Schematics, gerbers, drivers, etc., are available on my github repo. For more electronics and vintage computer videos, please see https://www.smbaker.com/