Editing Atari 7800 (section)

== Models and board revisions ==

<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:70%; text-align:left;"
|+'''7800 versions (ConsoleMods)'''
! Version !! Board !! Notes
|-
| NTSC, expansion port (1984 to 1987) || C025233-001; some later units C025233-002 || Unused expansion port on the left side. Units built in 1984 and 1985 were warehoused until the 1986 launch
|-
| NTSC, no expansion port (1987 to 1992) || C025233-002 || The port is left off, though its footprint remains on the board
|-
| PAL (1989 to 1993) || C300633-001 || Different faceplate, green power LED, ''Asteroids'' built into the BIOS, no cartridge signature check. French consoles have an RGB connector in place of the RF output
|}

All NTSC consoles check a digital signature in a 7800 cartridge before running it in 7800 mode; a cartridge without one runs in 2600 mode.<ref name="cmmodels" /><ref name="wp" /> Some C025233-002 boards carry an extra timing circuit around a 74LS02 (U13). ConsoleMods says it was added to fix 2600 compatibility with titles such as ''Kung-Fu Master'' and ''Dark Chambers'', but breaks some Activision 2600 games, among them ''The Activision Decathlon'', ''Robot Tank'' and ''Space Shuttle''. Some -002 boards have only a 0 Ω jumper where the circuit would be.<ref name="cmmodels" />

Atari's schematic for the NTSC console is drawing C025231-001, revision A, from 1984.<ref name="schem" />