Atari 5200
The Atari 5200 SuperSystem is a home video game console made by Atari, Inc. Atari announced it in June 1982 and shipped it in October 1982.[1] It uses the custom chips of the Atari 8-bit computers (ANTIC, GTIA and POKEY) with a modified 6502.[2] Atari's service manual covers NTSC units only; its power-up test treats a PAL GTIA as the wrong part for the unit.[2] The 5200 FAQ notes that the later boards have space for PAL circuitry.[3]
 | |
| Atari 5200 four-port model with a CX52 controller | |
| Specifications | |
|---|---|
| Manufacturer | Atari, Inc. |
| Type | Home video game console |
| Released | 1982 (four-port; shipped October 1982)[1] 1983 (two-port)[2] |
| CPU | Custom 6502 (Atari C014806) at U2/A2 |
| Memory | 16 KB DRAM |
| Storage | ROM cartridge |
| Display | ANTIC + GTIA |
| Sound | POKEY, 4 channels |
| OS / Firmware | BIOS ROM (Atari C019156) at U8/A8 |
| Predecessor | Atari 2600 |
| Model no. | CX5200 |
Atari's CX5200 Field Service Manual is the primary source for most of the detail below.[2]
The three main boards
editAtari's manual describes three main boards. Unless it says otherwise, the manual refers to the original board, and it warns that chip designators change from U to A on the later boards.[2]
| Board | Ports | Designators | Identification | Differences |
|---|---|---|---|---|
| CA018087 (original four-port) | 4 | U1–U29 | Needs retrofit kit CA023019 to work with the CX55 VCS cartridge adaptor | |
| CA020108 (four-port "universal") | 4 | A1–A28 | Serial number on the base has a + as its third character, e.g. AT+213 | U4 and U15 (74LS244) removed; U14 and U28 replaced by a 74LS125 at A14 and a 74LS51 at A15; provision for the VCS cartridge adaptor added |
| CA021374 (two-port) | 2 | A1–A28 | Two controller ports | As the universal board, plus: ports 3 and 4 and their components removed; A12 and A13 removed; manual switchbox and standard RF cable; the power adaptor plugs into the console |
The manual counts 28 ICs on CA018087, 26 on CA020108 and 24 on CA021374.[2]
Integrated circuits
edit| Function | Device | CA018087 | CA020108 / CA021374 |
|---|---|---|---|
| Microprocessor | Custom 6502, Atari C014806 | U2 | A2 |
| Display processor | ANTIC, Atari C012296 | U3 | A3 |
| Graphics | GTIA, Atari C014805 | U5 | A5 |
| Sound, pots, keypad scan | POKEY, Atari C012294 | U7 | A7 |
| BIOS ROM | Atari C019156 | U8 | A8 |
| Reset and video buffer | 4050B | U1 | A1 |
| Address decode | 74LS139 | U6 | A6 |
| Keypad multiplexers | 4052 | U9–U13 | A9–A13 (A12, A13 absent on the two-port) |
| DRAM address multiplexers | 74LS258 | U16, U17 | A16, A17 |
| RAM, eight 16K × 1 DRAMs | Atari C018082 | U18–U25 | A18–A25 |
| Power on/off latch | 4013B | U29 | A26 |
| +5 V regulators | 78M05 (Atari C014348) | VR1, VR2 | VR1, VR2 |
Locations and part numbers are from Atari's parts lists and schematic;[2][4] the functions are from the 5200 FAQ and the Console5 TechWiki, both secondary sources.[3][5]
The schematic draws the RAM as MB8118-12 with the note "typical 8 chips", and the ROM at U8 as "4096 × 8". The 5200 FAQ lists MK4516 RAMs and describes the ROM as a 2 KB BIOS holding the character set.[4][3]
Power
editFour-port: power through the switchbox
editThe original and universal four-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.[2][4]
- The power pack is the CX521 AC/DC power adaptor, Atari C018187, output 9.3 V DC at 1.95 A.[6] It is a linear supply: a transformer, an MDL-5 fuse, a bridge rectifier and a 3300 µF 25 V reservoir, all inside the pack.[4]
- Atari's Tech Tip 6 warns not to use an HCD power adaptor with the CX5200, as it will damage both the adaptor and the switchbox.[6]
- 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]
Two-port
editThe two-port console takes its own adaptor (Atari A.C. adaptor assembly CA021673) into a power jack at the rear of the case, and uses a manual switchbox.[2]
Inside the console
editRegulation is by two +5 V regulators, VR1 and VR2, on a heatsink assembly (CA019069 on the original board, CA020161 on the later boards). Atari's parts list gives the device as a 78M05 (C014348); the schematic prints LM340T-5. Each regulator works with an MJE-210 power transistor (Q6, Q7), and a +9 V source is taken from the supply as well as the +5 V rails.[2][4]
Readings from Atari's four-port snowy-screen flowchart (p. 4-9):[2]
| 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 | |
| Pin 13 of U29 (A26), the 4013 latch | Changes between 13 V and 0 V when the power switch S2 is pressed | Power latch circuit (flowchart D2, p. 4-11) |
| Pin 3 of the RF module | +5 V | L13, the RF module, or an open to VCC2 |
The two-port chart (p. 4A-10) checks for the LED, +5 V at the output of VR2, at least +7 V DC at its input, and the base-to-emitter drop of Q7 (0.7–1.0 V).[2]
The cartridge carries a +5 V link
editThe schematic marks a link between J1 pins 36 and 18 as "jumper in plug-in ROM cartridge", joining the two halves of the supply.[4] A 5200 with no cartridge fitted is therefore not fully powered, which matters when probing a "dead" console with an empty slot.
Capacitors
editThe 5200 has one aluminium electrolytic, C45, whose value depends on the board:[2][5]
| Ref | CA018087 (original four-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 | Polystyrene (C018621; an auto-insertable part, C018261, on the later boards) |
| 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 (two-port: C19, C99, C100, C105, C106 only) | Polyester, radial |
The rest are ceramic axials. Each column is from that board's own parts list.[2]
Diagnostics
editAtari's test cartridge for the 5200 is the Diagnostic Cartridge version 1.1, used with a Port Board (loop-back board) that makes it cycle through all its tests automatically. The menu keys are 1 Any Video, 2 Color Bars, 3 Gray Bars, 4 Port Test, 5 Pokey Adjust, 6 Tone Test, 7 RAM Test and 8 Verify OS ROM. The power-up screen shows NTSC if the GTIA is the right part for the unit.[2]
| Code | Failure |
|---|---|
| 0–7 | RAM chips 1–8: U25, U24, U23, U22, U21, U20, U19, U18 in that order |
| 8–11 | Ports 1–4, keyboard data |
| 12–15 | Triggers 0–3 |
| 16–19 | Soft fire 0–3 |
| 20, 21 | Serial port 0, 1 (not used) |
| 22–29 | Pot lines 0–7 |
| 30 | OS ROM (U8) |
If a RAM chip swap does not cure a RAM error, Atari swaps U15, U16, U17 and U28 on CA018087, or A14–A17 on CA020108.[2]
| Symptom | Possible causes |
|---|---|
| Solid coloured screen | U7, U2, U3, U5, Y1, Q1, Q2, VR1 |
| Vertically lined screen | J1, U2, U3, U5, U7, open or shorted data or address line |
| Snowy screen | VR2, U29 (A26), RF module |
| Warped picture (sync loss) | RF module, U1, U5, U3 |
| No colour | U5, Q3, C9, C11, Y1 |
| Weak colour | Q3, C11, C9, R29, R32 |
| Audio failures | U7, Q4, C14, C13, L1 |
| Only a few tones fail | U7 |
| Joystick does not work | Port, U5, U7, C91–C106, R106–R113 |
| Keypad does not work | Port, U9–U12 |
| Fire button does not fire | Port, U5, R114–R117, C107–C110 |
The colour adjustment is R8, set in the colour bar test so that the bars above and below the reference line are within one shade; the POKEY adjustment is R132, set so that port 1 horizontal reads 112 ± 1 on the Pokey Adjust screen.[2] Details are on the Atari 5200 General Maintenance page.
Controllers
editThe CX52 controller (Atari CA018107, all models) has an analogue joystick with two potentiometers, a 12-key keypad, two fire buttons on each side and three select buttons (START, PAUSE, RESET).[2] The keypad, fire buttons and select buttons run through a flex circuit.
Atari's controller tests:[2]
- With a console: on the Pokey Adjust screen, port 1 horizontal and vertical should read less than 25 with the stick at position 1 and more than 190 at position 2, and change evenly between them.
- Without a console: through the cable, pins 11 and 9 and pins 10 and 9 should read no more than 50 kΩ at position 1, and at least 430 kΩ more at position 2. Buttons read open when released and less than 50 kΩ when pressed.
- Pot alignment: with the arm off the wiper shaft, set the pot to 5–20 kΩ between terminals 2 and 3, refit the arm in position A of Atari's Figure 6-4, and repeat the cable test. If it still fails, replace the pots, and if the pots have already been replaced, replace the actuator plates, which come as a set with the slide block.
The stick does not centre itself. Atari published a boot replacement procedure with a revised top case (Tech Tip VCS 8), a knob puller tool FC100214 (Tech Tip 9) and a firmer replacement fire button C020501 (Tech Tip 10).[6]
Factory changes and tech tips
edit- Rockwell 6502 MPUs with date code 8250 and later (stamped RC) have a timing defect. Atari's factory change adds an R–C network on the component side at U14A pin 1 and U6A pin 4; it need not be removed when another MPU is fitted (Tech Tip VCS 7).[6]
- On CA018087 boards, a blank dark screen or a garbled screen, sometimes only when the board is flexed near J1, can be a solder bridge between the A0 address trace and the feed-through pad of the REF line near J1 (Tech Tip 12).[6]
- Signetics 74LS258 chips at A16 and A17 on the later four-port and two-port boards can corrupt RAM data, giving a scrambled screen or no video. The fix is a second 390 pF capacitor in parallel with C145 and a 470 Ω resistor from C137 to R134, or replacement with another maker's 74LS258 (Tech Tip 13). Some two-port units were built with 74LS158s at A16/A17 and matching board changes (Tech Tip 17).[6]
- Paddle jitter on CA018087 boards comes from ripple on the POKEY supply and a weak ground at U7 pin 1. The fix is a 10 µF tantalum capacitor across U7 pins 1 and 17 and an extra ground jumper (Tech Tip 14).[6]
- Original CA018087 boards need retrofit kit CA023019 for the CX55 VCS cartridge adaptor. Atari's procedure solders wires to pins 24, 30 and 11 of J1 and warns that if the red jumper wire is grounded, the 5200 power adaptor will burn out (Upgrade Bulletins 01 and 01A).[6]
Cartridge slot
editThe cartridge socket J1 is a 36-contact (18/36) board-mounted connector.[2] Its pins 18 and 36 carry the +5 V link described above.[4]
Maintenance and repair
editSchematics
edit| Motherboard | RF Switch Box and Power Supply | Accessories |
|---|---|---|
 |
 |
 |
Service documentation
edit- Atari CX5200 Field Service Manual (PDF): parts lists for all three boards, schematics, flowcharts, symptom checklists and controller service
- Atari 2600 and 5200 Field Change Orders, Upgrade Bulletins and Tech Tips (PDF)
Related pages
editReferences
edit- ↑ 1.0 1.1 Michael D. Current (ed.), Atari 8-Bit Computers: Frequently Asked Questions, comp.sys.atari.8bit FAQ, last modified 29 November 2009, history timeline for 1982. faqs.org. Community reference.
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 2.18 2.19 2.20 Atari, Inc., CX5200 Field Service Manual, FD100127 Rev. 4, July 1983 (ECN 0036, 21 June 1983, adds the 2-port model). Section 1 (board differences, pp. 1-1 to 1-8), Section 2 (silkscreens and schematics), Sections 3 and 3A (testing with the Diagnostic Cartridge version 1.1; Table 3-1 error codes, p. 3-9), Sections 4 and 4A (diagnostic flowcharts), Sections 5 and 5A (symptom checklists), Section 6 (game controller, pp. 6-1 to 6-13) and Section 8 (parts lists). Hosted here as Atari CX5200 Field Service Manual (PDF).
- ↑ 3.0 3.1 3.2 Keita Iida (ed.), Atari 5200 SuperSystem Frequently Asked Questions, version 3.3, 9 April 2001, sections 4.8 (differences between the 2-port and 4-port models) and 4.11 (logic board IC functions). atarihq.com. Community reference.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Atari, Inc., Atari 5200 Programmable Video Game System schematics: sheet 1 (processing, I/O, ROM and RAM) and sheet 2 of 2 (RF switchbox, modulator and power supply), 23 February 1983. See File:Schematic Atari5200 4000.png and File:Schematic Atari5200 RFSwitchbox 2000.png.
- ↑ 5.0 5.1 Console5 TechWiki, "Atari 5200", chip info and capacitor list. Secondary source (a capacitor-kit vendor's component list).
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 Atari, Inc., Atari 2600 and Atari 5200 Field Change Orders, Upgrade Bulletins, Tech Tips: Tech Tip 6 (CX5200 power adaptor, 17 November 1982), Tech Tip VCS 7 (Rockwell 6502, 20 January 1983), Tech Tip VCS 8 (controller boots, 20 January 1983), Tech Tips 9 and 10 (knob puller, fire button, 8 April 1983), Tech Tip 12 (6 June 1983), Tech Tip 13 (7 July 1983), Tech Tip 14 (8 July 1983), Tech Tip 17 (2 August 1983), and Upgrade Bulletins 01 and 01A (7 July 1983, 16 January 1984). Hosted here as Atari 2600 and 5200 Field Change Orders and Tech Tips (PDF).