Date   : Wed, 22 Sep 2010 04:36:48 +0200
From   : rick@... (Rick Murray)
Subject: 32K Message

On 21/09/2010 23:11, Matt Walker wrote:

> Here's a thing, why does the 32K message appear at power on and hard reset,
> but not after a soft reset?

Because it does. :-)

Perhaps as a message to the user to easily distinguish (both in message 
and sound) between a soft reset (memory intact) and a hard reset.

 From the annotated OS disassembly:
--8<--------
  DB67    AND     &0267   ;if A=&FE and bit 7 of 0267 is set then continue
  DB6A    BPL     &DB87   ;else ignore start up message
  DB6C    LDY     #&02    ;output to screen
  DB6E    JSR     &DEA9   ;'BBC Computer ' message
  DB71    LDA     &028D   ;0=warm reset, anything else continue
  DB74    BEQ     &DB82   ;
  DB76    LDY     #&16    ;by checking length of RAM
  DB78    BIT     &028E   ;
  DB7B    BMI     &DB7F   ;and either
  DB7D    LDY     #&11    ;
  DB7F    JSR     &DEA9   ;finishing message with '16k' or '32k'
  DB82    LDY     #&1B    ;and two newlines
  DB84    JSR     &DEA9   ;
--8<--------


Best wishes,

Rick.

-- 
Rick Murray, eeePC901 & ADSL WiFI'd into it, all ETLAs!
BBC B: DNFS, 2 x 5.25" floppies, EPROM prog, Acorn TTX
E01S FileStore, A3000/A5000/RiscPC/various PCs/blahblah...