GTIA Fixer

This adapter addresses a common fault found in Atari 8-bit systems manufactured from the 38th week of 1990, mainly 800XE, some XEGS, 130XE and 65XE machines. This fault leads to improper operation in the so-called GTIA modes (graphics modes 9, 10, and 11 in BASIC). Original idea of the adapter by Simius.

Adapter features

• Fixes video problems / GTIA faults (both types)
• "Deaf" GTIAs with faulty sound output can be used again as device also generates GTIA sound
• Fixes configurable with jumpers on the right hand side of the PCB

Installation

• Desolder GTIA
• Solder GTIA Fixer
• Insert GTIA into the socket on the adapter
• Connect external PC buzzer (supplied)

Jumpers description

• JP1 (AN[2:0] signals from ANTIC are clocked and D-ffed to GTIA, modified OSC signal for GTIA)
  • open- default -  fix for fault of type 1 enabled
  • closed -  fix for fault of type 1 disabled
• JP2 (Antic gets OSC signal in place of Phio from GTIA)
  • open - default -  fix for fault of type 2 disabled
  • closed - fix for fault of type 2 enabled

Other 6 pins are CPLD JTAG header.