Changes
The AMRAM has two PCBs sitting on top of each other, joined with a rigid connector.
On the bottom is passthrough for other expansion connectors and a 3V square lithium battery. (The exact replacement battery is expensive. It *is* possible to fit a PC CMOS compatible lithium battery (CR2032) and holder, but it's not as neat and there is not a lot of space between the two pcb boards of the Amram)
On the top, 32K RAM (contents are held by lithium battery so can survive a reset or power off), which can be programmed like ROM and occupies two ROM positions (1 and 2) and also sockets for expansion ROMs up to ROM 7.
