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   comp.sys.apple2      Discussion about Apple II micros      56,720 messages   

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   Message 54,945 of 56,720   
   Andrew Roughan to All   
   Transwarp behaviour with ROMX   
   01 Sep 21 06:02:12   
   
   From: no_email@invalid.invalid   
      
   The Transwarp manual says:   
      
   The only way to activate TransWarp is by powering-up, or "cold-booting",   
   the computer.   
   …   
   Accesses to the Apple's RAM and ROM are restricted to the Apple's clock   
   rate of   
   1 MHz; therefore, on power-up, TransWarp loads the Apple's ROM into its   
   RAM,   
   …   
   Writing a three (to $C074) will disable the TransWarp card completely and   
   pass processing control to the Apple's processor until the TransWarp is   
   again activated by cold-booting the system.   
   —-   
      
   This combination of behaviour makes coexistence with ROMX difficult.   
   Transwarp will shadow ROMX bank 0 at startup and then any attempt by ROMX   
   to change ROM is not actioned by TW.   
      
   If the TW is disabled to allow ROMX to function, can’t return to fast   
   speed.   
      
   Is there a way to force TW to update its ROM shadow copy?   
   E.g. Is there a way to force TW to think it has been cold booted without   
   also making ROMX think it has been cold booted?   
   Potentially a hardware switch.   
      
   Alternatively, can a new TW firmware help?   
   The firmware disassembly shows $1000 org which must be an internal address   
   space. There is no slot firmware visible when the TW is disabled.   
   Potentially a different firmware could be written to allow ROMX to do its   
   thing and then invoke shadow copy. Not sure if this is feasible.   
      
   Any other ideas?   
   Any input in the above?   
      
   Thanks   
   Andrew   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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