Please, check our SMD/THT services - smd.lotharek.pl; from idea to ready devices                                                                                                                                   

Please, check our SMD/THT services - smd.lotharek.pl; from idea to ready devices                                                                                                                                   

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OS ROM switcher

OS ROM switcher

Discontinued

Like Ask Tell

 

 

ROM switcher for ATARI 8bit 

  • device replaces orginal ATARI ROM chip 
  • ATARI OS / QMEG 4.04 flashed
  • active OS ROM selected with RESET during power on of computer
  • bottom jumper to select default ROM. 

 

How does it work ?

    After power on ONLY, initial RESET button state is stored by flip-flop clocked by 10ms rising edge. Data input is 1 for RESET buton NOT pressed, 0 for pressed. Stored input selects "half" of programmed flash memory. Simple end efficient.

 

STEP BY STEP:

  • replace orginal rom with OS ROM switcher
  • connect 1 wire to RESET L14 at ATARI PCB  - ususally next to keyabord connector.

 

 

That is all :-)

 

if  You are lucky and Your atari OS ROM is socketed, upgrade will take 30 seconds. If not - longer ;-) - desoldering time :-)

 

 

 

DISCLAIMER: not for ULTIMATE 1MB users. 

 

 

 

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