AMRAM is a 16K RAM which acts like a ROM made by Silicon Systems. See also: AMRAM2
According to a review in Amstrad Action, Amram has two banks of 8KB occupying ROM 5. There is a write enable switch, which must be enabled for writes to be allowed and a green led lights up when the Amram is being written to.
It is reviewed in Amstrad Action issue 19.
Amram user manual
Media:Amram.pdf Manual as PDF file