Hi,

The Dallas 87C520 (=80C320 + 16K eprom)has a ROMSIZE SFR (located at C2H) that allows the user to set the maximum on-chip program memory addresss. Higher address program code is fetched off-chip.

The Winbond W77E58 in all aspects is a very nice replacement for the 87C520 (it has a 32K flash and will go to 40MHz) but the datasheet isn't clear about support for the ROMSIZE SFR. It has a ROMMAP at C2H that seems to contain the correct value in b2-b0 (110) to indicate a 32K on-chip program memory. It doesn't say though if this value can be changed.

So I was wondering, has anybody out there ever used this SFR on a W77E58 ?

best,
Anton