DavidMil Posted May 17, 2017 Author Share Posted May 17, 2017 There isn´t any magic... Portbit B1 (Bit 1 of Port B, pin 11 of PIA 6520 chip) is connected to the MMU. The MMU manages memory, ROM, cartridge(s), internal basic and I/O access to the whole 64 KB address space. When this portbit is set to 0, the internal BASIC ROM is enabled. A "1" means "BASIC disabled". The MMU´s logic checks this portbit and decides to map normal memory (BASIC disabled) or the BASIC ROM in the area between $A000 and $BFFF. If a cartridge (at least 8 KB one) is inserted, then internal BASIC is always seen "disabled", not depending on the status of Portbit B1. The XL/XE O.S. just checks during coldstart if OPTION is held - if OPTION is held, the value 1 is written to address 1016 (decimal). Otherwise 1016 is set to zero. This value is used during every RESET (also warmstart) to set portbit B1 to 0 or 1... Thank you Rybags. This is the answer I was looking for. One more question to all... Is the same size dwarf used in the 130XE as the 800? And if so how do they fold him to get him in there? David Quote Link to comment Share on other sites More sharing options...
Joey Z Posted May 17, 2017 Share Posted May 17, 2017 (edited) Thank you Rybags. This is the answer I was looking for. One more question to all... Is the same size dwarf used in the 130XE as the 800? And if so how do they fold him to get him in there? David there was no dwarf on the 800, back then you had to have a BASIC cart, and get angry and pull it out yourself. Unless you mean the 800XL, in which case one dwarf fits all. Edited May 17, 2017 by Joey Z 1 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted May 17, 2017 Share Posted May 17, 2017 (edited) it's simple they select different graphics mode to compress the dwarf between the 130xe and 800xl locations... for the 800 you 'be the dwarf' Edited May 17, 2017 by _The Doctor__ 1 Quote Link to comment Share on other sites More sharing options...
DavidMil Posted May 17, 2017 Author Share Posted May 17, 2017 God knows I been the dwarf many, many times! Thanks everyone for another interesting thread! David Quote Link to comment Share on other sites More sharing options...
baktra Posted May 17, 2017 Share Posted May 17, 2017 it's simple they select different graphics mode to compress the dwarf between the 130xe and 800xl locations... for the 800 you 'be the dwarf' I feed and water the dwarfs by regular playing Picnic Paranoia, Pieman, and Tapper. They also find the fruits from Vegas Jackpot very sweet and tasty, 3 Quote Link to comment Share on other sites More sharing options...
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