Date   : Fri, 17 Nov 2006 12:03:04 +0000 (GMT)
From   : hick.bbc@... (gARetH baBB)
Subject: Memory map questions

On Mon, 13 Nov 2006, Thomas Harte wrote:

> Does anybody have documentation for the layout of BBC BASIC programs in 
> RAM? I'm really only interested in BASIC II as shipped with the 
> Electron, but any information would be gratefully accepted.

You want the BASIC ROM User Guide. To summarise:

00 Line number MSB
01 Line number LSB
02 Length
03 data, terminated by CR

MSB with high bit set is end of program.

> Similarly, does anybody know whereabout in RAM the OS keeps a list of 
> the available paged ROMs? I know it does a check to see which ones are 
> installed at startup, but does it keep a list of which are installed and 
> what type they are anywhere?

The ROM type table is at &24x I think.

You should use OSBYTE 170 and 171 to get the proper position of this 
table.