CTIA C012295 / GTIA C014805 pinout

DIP-40. Color, luminance and sync out, player/missile graphics, triggers and console keys; divides the color clock for ANTIC.

GTIA turns ANTIC playfield data and player/missile data into color, luminance and sync, reads the four joystick triggers and the console keys, and drives the keyboard click. It takes the 3.58 MHz color clock on OSC and gives ANTIC the fast phase 0 clock, so a dead GTIA can stop the machine. Early 400/800s have the CTIA, which has three luminance lines and a second chip select on pin 31; the GTIA (C014805, NTSC) uses pin 31 as a fourth luminance line. Software written for GTIA modes 9-11 shows garbage on a CTIA.

Open the interactive GTIA pinout

Pins

Pin	Name	Type	Signal
1	A1	addr	Address bus bit 1 (register select).
2	A0	addr	Address bus bit 0 (register select).
3	Vss	ground	0 V.
4	D3	data	Data bus bit 3.
5	D2	data	Data bus bit 2.
6	D1	data	Data bus bit 1.
7	D0	data	Data bus bit 0.
8	T0	io	Trigger 0: fire button of controller 1 (port pin 6). 220 Ω series resistor on the 130XE.
9	T1	io	Trigger 1: fire button of controller 2.
10	T2	io	Trigger 2: controller 3 on the 400/800. Not connected on the 130XE.
11	T3	io	Trigger 3: controller 4 on the 400/800. On the 130XE it reads cartridge line RD5 (cartridge present).
12	S0	io	Console switch line 0. UNVERIFIED
13	S1	io	Console switch line 1. See pin 12 on the key names.
14	S2	io	Console switch line 2. See pin 12 on the key names.
15	S3	audio	Console line 3: keyboard click to the speaker (the 800XL manual: Keyboard Click).
16	PAL	ctrl	PAL color delay (PAL/NTSC timing).
17	DEL	video	Color delay (CADJ on the XL/XE), set by the color adjust pot. Wrong hues: adjust here first.
18	AN0	video	Alphanumeric data bit 0 from ANTIC pin 2.
19	AN1	video	Alphanumeric data bit 1 from ANTIC pin 3.
20	AN2	video	Alphanumeric data bit 2 from ANTIC pin 5.
21	COL	video	Color (chroma) output.
22	LUM0	video	Luminance output 0.
23	LUM1	video	Luminance output 1.
24	LUM2	video	Luminance output 2.
25	CSYNC	video	Composite sync output.
26	/HALT	ctrl	HALT line from ANTIC pin 9.
27	Vdd	power	+5 V supply.
28	OSC	clock	Color clock oscillator input.
29	FPHI0	clock	Fast phase 0 clock out to ANTIC pin 35.
30	PHI2	clock	Phase 2 clock in.
31	LUM3	video	GTIA: fourth luminance line. On the CTIA this pin is CS2, a second chip select. UNVERIFIED
32	/CS	ctrl	Chip select ($D0xx). LOW selects GTIA.
33	R/W	ctrl	Read or write.
34	D7	data	Data bus bit 7.
35	D6	data	Data bus bit 6.
36	D5	data	Data bus bit 5.
37	D4	data	Data bus bit 4.
38	A4	addr	Address bus bit 4 (register select).
39	A3	addr	Address bus bit 3 (register select).
40	A2	addr	Address bus bit 2 (register select).

Fitted in

Atari 400 A301 (CPU board)
Atari 800 A301 (CPU board)
Atari 600XL
Atari 800XL U17
Atari 130XE U17

CTIA C012295 / GTIA C014805 pinout

Pins

Fitted in

Sources