Atari 5200

Atari 5200

Atari 5200 4-port model with controllers
Specifications
Manufacturer	Atari, Inc.
Type	Home video game console
Released	November 1982 (4-port) 1983 (2-port)
Intro price	US$269 (1982)
CPU	6502 variant, Atari C014806, at U2/A2
Memory	16 KB DRAM
Storage	ROM cartridge
Display	ANTIC + GTIA, NTSC only
Sound	POKEY, 4 channels
OS / Firmware	2 KB ROM (Atari C019156)
Predecessor	Atari 2600
Model no.	CX5200

The Atari 5200 SuperSystem is a home video game console released by Atari, Inc. in November 1982. It uses the same custom chipset as the Atari 8-bit computer line — ANTIC, GTIA and POKEY around a 6502 — in a console package. It was sold in North America only; there was never a PAL Atari 5200.

This page concentrates on the information a repairer needs. Atari's CX5200 Field Service Manual is the primary source for almost everything below.

The three PC boards

Atari shipped three different main boards, and they are not interchangeable for service purposes — the designator prefix itself changes between them.

Production boards

Board	Ports	Designators	Identification	Notes
CA018087 (original 4-port)	4	U1–U29	—	Needs retrofit kit CA023019 to work with the CX55 VCS cartridge adaptor
CA020108 (4-port "Universal")	4	A1–A28	Serial number on the base has a + as its third character	U4 and U15 (74LS244) deleted; U14 and U28 replaced by a 74LS125 at A14 and a 74LS51 at A15; provisional circuitry for the VCS cartridge adaptor added
CA021374 (2-port)	2	A1–A28	Two controller ports	As the Universal board, plus: ports 3 and 4 and their discrete components removed; A12 and A13 removed; manual switchbox instead of the automatic one; the power adaptor plugs into the console instead of the switchbox

Atari's serial-number identification for the Universal board is a plus sign as the third character, for example "AT+213…". Collectors usually call this the "asterisk" board.

Integrated circuits

Chip locations

Function	Device	CA018087	CA020108 / CA021374
Microprocessor	Atari C014806 (6502 variant)	U2	A2
Display list processor	ANTIC, Atari C012296	U3	A3
Graphics	GTIA, Atari C014805	U5	A5
Sound, pots, keypad scan	POKEY, Atari C012294	U7	A7
System ROM	Atari C019156 (4096 × 8)	U8	A8
Reset and video buffer	4050	U1	A1
Address decode	74LS139	U6	A6
Keypad multiplexers	4052	U9–U13	A9–A13 (A12, A13 absent on the 2-port)
DRAM address multiplexers	74LS258	U16, U17	A16, A17
RAM, 8 × 16 K × 1 DRAM	MB8118 or 4516 family	U18–U25	A18–A25
Power on/off latch	4013	U29	A26
+5 V regulators	78M05 (Atari C014348)	VR1, VR2	VR1, VR2

The 6502, ANTIC, GTIA, POKEY and ROM identifications come from Atari's parts lists and the console schematic; the remaining functional descriptions are from the Console5 TechWiki, a secondary source.

The 5200 schematic marks the RAM as MB8118-12 with the note "typical 8 chips"; Console5 lists the equivalent 4516. Either way these are 16 K × 1 dynamic RAMs, eight of them, giving 16 KB.

Power

This is where the 4-port and 2-port machines genuinely differ, and where most surviving 5200s fail.

4-port: power through the switchbox

The original and Universal 4-port consoles have no power connector of their own. Power and RF share one cable to the CX522 switchbox, which also contains a relay that switches the television between aerial and console.

• Power pack: CX521 AC/DC Power Adaptor, Atari P/N C018187. Output: 9.3 volts DC at 1.95 A. It is a linear supply: transformer, bridge rectifier, a 3300 µF/25 V reservoir and an MDL-5 fuse, all inside the brick.
• Atari's tech tip warns explicitly: do not use an HCD power adaptor with the CX5200 — it will damage both the adaptor and the switchbox.
• The switchbox select switch has two positions: NORMAL, which lets the console switch the television automatically when the power switch is pressed, and STANDBY, which allows television viewing while the console is on.

2-port

The 2-port console takes its own adaptor (Atari A.C. adaptor assembly CA021673) directly into the rear of the case, and uses a conventional manual switchbox.

Inside the console

Regulation is by two +5 V regulators, VR1 and VR2, on a heatsink assembly (Atari CA019069). Atari's parts list gives the device as a 78M05 (C014348, the 500 mA part, the same regulator used in the Atari 2600); the slightly earlier schematic prints LM340T-5. Each regulator works with an MJE-210 power transistor, and a +9 V rail is taken from the unregulated supply as well as the two +5 V rails.

Expected readings, from Atari's diagnostic flow charts:

Test point	Expected	If wrong
Core of J3 (power/RF input)	10–12 V DC	RF cable, switchbox or power pack
Input of VR2	+12 V
Output of VR2 (pin 3)	+5 V	Check for a short on the output
Pin 13 of U29 (A26), the 4013 latch	Toggles between 13 V and 0 V when the power switch S2 is pressed	Power latch fault
Pin 3 of the RF module	+5 V	L13, the RF module, or an open to VCC2

The cartridge carries the +5 V jumper

The console's +5 V distribution is jumpered through the cartridge: the schematic marks a link between J1 pins 36 and 18 as "jumper in plug-in ROM cartridge". A 5200 with no cartridge in the slot is therefore not fully powered. This is designed behaviour, not a fault, and it is worth knowing before you start probing a "dead" console with an empty slot.

Capacitors

The 5200 has remarkably few aluminium electrolytics — essentially one, and its value depends on the board:

Ref	CA018087 (original 4-port)	CA020108 and CA021374	Type
C45	4700 µF 25 V (Atari C016033)	47 µF 25 V (Atari C020121)	Electrolytic, radial
C41, C42, C119, C144	10 µF 20 V	10 µF 20 V	Tantalum, axial
C13, C14	820 pF 25 V	820 pF 25 V	Polystyrene, audio circuit (Atari C018621)
C43, C44	0.22 µF 100 V	0.22 µF 100 V	Polyester, radial
C19, C99–C106	0.047 µF 100 V	0.047 µF 100 V	Polyester, radial

Everything else on the board is a ceramic axial. The big 4700 µF at C45 on the original 4-port board is there because that board's supply comes through the switchbox cable; the later boards, which take a shorter or separate supply path, use only 47 µF in the same position.

Controllers

The CX52 controller (Atari CA018107, used on all models) has an analogue joystick, a 12-key keypad, two fire buttons on each side and three select buttons. The keypad, fire buttons and select buttons all run through a single flex circuit, which is the controller's main wear item.

On the console side, the keypad matrix is scanned through five (or three, on the 2-port) 4052 analogue multiplexers, with a 470 Ω series resistor and a 470 pF capacitor on each port line. A controller fault that affects one port only is usually the flex circuit or the port's 4052; a fault affecting all ports points at POKEY.

Atari's potentiometer adjustment procedure gives real numbers to work to:

1. With the arm off the wiper shaft, adjust the shaft so that the reading between pot terminals 2 and 3 is 5 kΩ–20 kΩ.
2. Fit the arm in the documented position and reassemble.
3. With the joystick at position 1, the reading through the cable (connector pins 11 and 9, and pins 10 and 9) should be no greater than 50 kΩ.
4. At position 2 the reading should be at least about 100 kΩ greater than at position 1.
5. If the test fails, replace the pots; if the pots have already been replaced, replace the actuator plates, which must be replaced as a complete unit with the slide block.

The non-centring design uses a rubber boot rather than springs. Atari published a boot replacement procedure and a knob puller tool (FC100214) because the knob is difficult to remove without one.

Known factory faults

• Rockwell 6502 MPUs with date code 8250 and later (stamped with the letters RC) have a timing defect. Atari's factory modification adds an R–C network on the component side of the board at U14A pin 1 and U6A pin 4. The network does not need to be removed to use another manufacturer's MPU or a Rockwell part with a different date code.
• CX55 VCS cartridge adaptor compatibility. Original CA018087 boards need retrofit kit CA023019, which solders wires to pins 24, 30 and 11 of J1. Atari's procedure carries an explicit warning: if the red jumper wire is grounded, the 5200 power adaptor will burn out.

Cartridge slot

The cartridge socket J1 has at least 36 positions; the +5 V jumper occupies pins 18 and 36.

Maintenance and repair

• Main article: Atari 5200 General Maintenance

Schematics

Atari 5200

Motherboard	RF Switch Box and Power Supply	Accessories
Atari 5200 Console Schematic	Atari 5200 RF Switchbox and Power Supply Schematic	Atari 5200 Accessories Schematic

Service documentation

• Atari CX5200 Field Service Manual (PDF) — parts lists for all three boards, schematics, flow charts and controller service
• Atari 2600 and 5200 Field Change Orders, Upgrade Bulletins and Tech Tips (PDF)

Related pages

• Atari 5200 General Maintenance
• Atari 2600