Atari 8-Bit Family Machine Hub
400/800, 600XL/800XL & 65XE/130XE workbench reference — "Ingot" PSU danger alert, ANTIC/GTIA/POKEY/SALLY diagnostics, Micron DRAM locator, 800XL S-Video Chroma & UAV mods, and SIO/PBI/ECI pinouts.
Atari XL/XE "Ingot" Power Supply Danger — DO NOT USE EPOXY-POTTED BRICKS!
Just like the Commodore 64's "Brick of Death", Atari's 600XL, 800XL, 65XE, 130XE, and XEGS have NO internal voltage regulator — they rely entirely on the external 7-pin DIN power brick to supply regulated +5.0 V DC (at 1.5 A) straight to the `SALLY`, `ANTIC`, `GTIA`, `POKEY`, and `4164` DRAMs. One specific original Atari supply — universally known as the "Ingot" (Part `CO61982` / `CA017964`, smooth bevelled brown/black wedge with NO ventilation slots, completely filled with solid epoxy resin) — overheats internally until its 7805 regulator fails short-circuit, dumping +9 V to +11 V DC straight into the computer and instantly killing all eight DRAM chips and custom VLSI chips!
1 Safe vs. Deadly XL/XE Power Bricks
- DEADLY — The "Ingot" (`CO61982` / `DV-515`): Heavy, smooth, angled trapezoid block with no vents and no screws (potted in rock-hard epoxy). Cut the 7-pin DIN cord off to build a USB-C / MeanWell cable and throw the brick away immediately!
- REPAIRABLE — "Black Beauty" (Finned / Vented) & "White Beauty" (`CA016804`): Have screws/vents and aren't potted in epoxy, so their internal filter caps and 7805/LM317 can be serviced — though a modern switching PSU with overvoltage protection is still far safer.
- Note on Atari 400 / 800 / 1200XL / 1050 Drive: Unlike the 600XL/800XL/XE, the Atari 400, 800, 1200XL, and 1050 Disk Drive use a simple 9 V AC (15–31 VA) transformer with a 3.5 mm or barrel plug (all DC regulation happens inside those machines!).
2 7-Pin DIN XL/XE Power Pinout (+5V DC)
Viewed looking at the rear female 7-pin DIN socket on the 600XL / 800XL / 65XE / 130XE / XEGS (or solder side of the male DIN plug):
| DIN-7 Pin | Signal | Target Spec |
|---|---|---|
| Pin 1, Pin 4, Pin 6 | +5.0 V DC (Bridged) | 4.95–5.15 V DC (@ 1.5–2.0 A) |
| Pin 2, Pin 3, Pin 5 | GND (0 V) (Bridged) | System Return Ground |
| Pin 7 (Center) | Shield / NC | Leave unconnected or shield |
Why 3 Pins Are Used in Parallel: A single DIN pin is only rated for ~1 A continuous without heating up. Always bridge Pins 1+4+6 for +5 V and Pins 2+3+5 for GND when soldering a new USB/5 V cable!
3 Atari 800 Power Board (+5V/+12V/-5V)
- Inside the classic Atari 800 (and 400), the 9 V AC input is rectified on the side power board into +5 V, +12 V, and −5 V because the 400/800 RAM cards use triple-rail 4116 DRAMs!
- Always replace the two big axial filter capacitors (`4700 μF 16V` / `2200 μF 25V`) on the 400/800 power board and clean the gold card-edge fingers on the CPU, OS, and RAM cards with DeoxIT.
Model Selector & Custom Chipset Architecture
Explore Jay Miner's pioneering co-processor architecture (`ANTIC`, `GTIA`, `POKEY`, `SALLY`) across the 400/800, XL, and XE generations.
Atari 600XL / 800XL / 1200XL 1983–1985 • Brown & Brushed Aluminium • PBI Bus
The iconic Atari 800XL consolidated the multi-board Atari 800 into a single compact motherboard with 64 KB of RAM, built-in Atari BASIC (which can be disabled at boot by holding the silver OPTION key!), a built-in diagnostic self-test ROM, and the rear 50-pin Parallel Bus Interface (PBI). Its smaller sibling, the 600XL, shipped with 16 KB RAM (two `4416` chips) and can be upgraded to a full 64 KB 800XL in 10 minutes by swapping in two `4464` DRAMs and soldering 3 jumper wires!
Core Custom Silicon Quartet
- SALLY 6502C (`CO14806` — U8): Custom Atari 6502 @ 1.79 MHz (NTSC) / 1.77 MHz (PAL) adding Pin 35 (`/HALT`) so ANTIC can pause the CPU cleanly during display list DMA without external tri-state bus buffers!
- ANTIC (`CO12296` NTSC / `CO21697` PAL — U7): Direct Memory Access display processor executing its own programmable Display Lists, fine scrolling, Display List Interrupts (DLIs), and DRAM refresh.
- GTIA (`CO14805` NTSC / `CO14889` PAL — U17): Graphic Television Interface Adapter — 256-colour palette (16 hues × 16 luminances), 4 hardware Player/Missile sprites, collision detection, and `START`/`SELECT`/`OPTION` console key reading + internal keyclick speaker output.
- POKEY (`CO12294` — U20): Potentiometer & Keyboard Integrated Circuit — 4-channel audio synthesizer + polynomial noise/random number generator + 64-key matrix scanner + 8 paddle ADCs + high-speed SIO Serial UART!
- PIA (`6520` / `6821` — U23): Port A reads the two DE-9 joystick ports; Port B (`$D301`) controls ROM/RAM bank switching and Self-Test ROM enable!
- MMU (`CO61618` — U3, PAL16L8): 20-pin memory management PAL decoding RAM, OS ROM (`U5`), BASIC ROM (`U4`), and `$D000–$D7FF` hardware registers.
600XL Easy 16K → 64K Upgrade & 800XL Keyboard Types
| Topic | Bench Procedure & Identification |
|---|---|
| 600XL 2-Chip 64KB RAM Upgrade | Replace the two socketed 18-pin `4416` (`16K×4`) chips at `U11` & `U12` with two `4464` (`64K×4`) DRAMs, lift Pin 6 of `U6` (`74LS158`) and Pin 3 of `U5`, and run 3 jumper wires for `A14` and `A15` — instant 64 KB 800XL with zero expansion box needed! |
| 5 Different 800XL Keyboard Mechanisms! | Atari sourced 800XL keyboards from 5 vendors: (1) ALPS (discrete mechanical switches — gold standard!), (2) Stackpole (white square plungers), (3) Mitsumi (Mylar membrane), (4) AWI (foam-and-foil/Mylar), and (5) Hi-Tek. On Mitsumi Mylar keyboards, clean the oxidised 24-pin ribbon tail with a soft white eraser or install a new Mylar sheet. |
Atari 65XE / 130XE / 800XE & XEGS 1985–1992 • ST-Style Case • FREDDIE & 128KB Banked RAM
Styled in cool grey with angled function keys to match the 16-bit Atari 520ST, the 65XE (64 KB) and 130XE (128 KB) introduce the 40-pin FREDDIE (`CO61922` / `CO61991`) RAM controller IC (replacing the discrete 74LS158 DRAM multiplexers and dividing the 14.318 MHz clock) and replace the rear 50-pin PBI slot with the dual Cartridge + ECI (Enhanced Cartridge Interface) connector.
130XE 128KB Bank-Switched Architecture
- FREDDIE (`CO61991` — U20): 40-pin DIP integrating the 14 MHz/3.58 MHz/1.79 MHz clock dividers and DRAM `/RAS` + `/CAS` row/column address multiplexing.
- EMMU (`CO25953` — U22 on 130XE): 16-pin Extended Memory Management PAL decoding PIA Port B (`$D301` bits 2–5) to bank four 16 KB extended RAM banks into the `$4000–$7FFF` window (independently selectable for the CPU and for ANTIC!).
- RAM Population: Early 130XEs use 16× 4164 DRAMs (`U26–U33` = Base 64K; `U9–U16` = Extended 64K — almost always failure-prone Micron `MT4264` chips!). Late 65XE/130XE boards condense RAM to two or four `4464` (64K×4) chips.
- Single 16KB OS ROM (`U4` — `CO61598B`): 28-pin JEDEC pinout + 8 KB Atari BASIC Rev C (`CO24947A`) in `U5`!
XL vs XE Hardware & Bench Comparison
| Feature | Atari 800XL | Atari 130XE |
|---|---|---|
| RAM Capacity | 64 KB (8× 4164) | 128 KB (16× 4164 or 4× 4464) |
| DRAM Multiplexer | 2× 74LS158 (`U26` / `U27`) | FREDDIE (`CO61991`) + EMMU (`CO25953`) |
| Built-in BASIC Version | Rev B (buggy!) or Rev C | Rev C (`CO24947A` — bug-fixed!) |
| S-Video Chroma on DIN-5 | Missing on stock 800XL (easy 1-wire mod!) | Connected on Pin 5 from factory! |
| Expansion Bus | 50-Pin Rear PBI Edge | 15-Pin Cart + 14-Pin ECI Rear Edge |
Atari 400 & Atari 800 1979–1983 • Cast-Aluminium RF Cage • 4 Joystick Ports
To pass strict FCC Class B RF emission rules in 1979, Atari encased the 400 and 800 motherboards inside heavy die-cast aluminium Faraday shields. The Atari 800 features a removable top hatch housing a 10 KB Personality (OS) ROM card and up to three 16 KB RAM cards (48 KB total), two cartridge slots (`Left` and `Right`), and four front DB9 joystick ports (driven by the 6520 PIA!). The Atari 400 features a spill-proof flat membrane keyboard and a single internal RAM card slot (upgradeable to 48 KB).
CTIA vs GTIA Upgrade & CPU Card Notes
- CPU Card: Early 400/800 CPU cards use a standard MOS 6502B plus three 74LS logic chips to implement `/HALT` bus disconnect; late 400/800 CPU cards use the single-chip SALLY 6502C (`CO14806`).
- CTIA (`CO10745`) vs GTIA (`CO14805` / `CO14889`): Very early 1979–81 400/800s shipped with the CTIA chip (128 colours, lacks GTIA modes 9, 10, 11). A 40-pin GTIA is a 100% direct drop-in replacement on the CPU card!
Atari 800 Modular Card Edge Cleaning
Whenever an Atari 800 boots to a black/brown screen or reports less than 48 KB in `PRINT FRE(0)` (`37902` bytes free with BASIC Cartridge in Left Slot = healthy 48K):
- Pop open the top RAM/ROM bay and pull out the 10K OS Card and all three 16K RAM Cards.
- Buff the gold PCB edge fingers on every card (AND on the hidden CPU Card inside the rear cast-aluminium cage!) with a soft white eraser and 99% IPA.
Diagnostic Checklist, Micron DRAM Locator & Mylar Repair
Decoding the "Red/Rust Screen of Death", using the built-in Self-Test ROM/RAM bars, and replacing Micron `MT4264` DRAMs.
"Solid Red / Rust-Brown Screen" & 800XL / 130XE 4164 DRAM Chip Locator
On an 800XL, 65XE, or 130XE, booting to a solid Red, Brick-Brown, or Maroon screen (or immediately dropping into the built-in `SELF TEST` screen with red RAM blocks!) is the classic Atari 8-bit failure signature. Good news: a solid red/brown raster proves your GTIA, ANTIC video sync, and master clock are alive — the CPU crashed during initial Zero-Page RAM or OS ROM verification!
4164 DRAM Bit-to-IC Map (800XL vs 130XE)
If your 800XL or 130XE contains Micron Technology `MT4264` DRAM chips (with the stylized `M` logo), expect them to fail in batches!
| Data Bit | 800XL IC (64K Main) |
130XE Base 64K (Main RAM) |
130XE Ext 64K (4×16K Banks) |
|---|---|---|---|
| Bit 0 (D0) | U9 | U26 | U9 |
| Bit 1 (D1) | U10 | U27 | U10 |
| Bit 2 (D2) | U11 | U28 | U11 |
| Bit 3 (D3) | U12 | U29 | U12 |
| Bit 4 (D4) | U13 | U30 | U13 |
| Bit 5 (D5) | U14 | U31 | U14 |
| Bit 6 (D6) | U15 | U32 | U15 |
| Bit 7 (D7) | U16 | U33 | U16 |
Using the Built-in Self-Test & Star Raiders Cart Trick
- Boot While Holding OPTION: Holding OPTION during power-on disables built-in BASIC (`U4`) and jumps straight to the Built-in Self-Test (if no disk drive responds). In the `MEMORY` test:
- 2 Rows of `ROM` Bars: Green = OS ROM checksum OK; Red = bad OS ROM (`U5`) or MMU (`CO61618`).
- 48 `RAM` Squares (1KB each) + 4 Extended Banks (on 130XE): A red square + error tone indicates a bad 4164 DRAM! (Note: if Low RAM `$0000–$07FF` is dead, the Self-Test cannot even start and shows a solid Red/Black screen).
- The `Star Raiders` / `Sys-Check V2.2` Cartridge Trick: A diagnostic cartridge (like Sys-Check II on the rear PBI/ECI bus) or an early 8 KB game cart (`Star Raiders` requires only the bottom 8 KB of RAM!) immediately tells you whether `SALLY`, `ANTIC`, `GTIA`, and `MMU` are healthy when the OS ROM or upper RAM is dead!
POKEY (`CO12294`) Failure Symptoms & Replacements
Because POKEY handles four different subsystems on one 40-pin chip, a damaged POKEY causes a distinctive combination of symptoms:
- 1. Keyboard Completely Dead (OR Repeating Phantom Keys on Boot): POKEY Pins 10–15 (`K0–K5`) and Pin 16 (`KR1`) / Pin 24 (`KR2` — Shift/Ctrl/Break) scan the entire 64-key matrix via two `4051` CMOS analog multiplexers (`U18` & `U19` on 800XL)! Before blaming POKEY for a dead keyboard, swap or test the two cheap 16-pin `CD4051BE` multiplexers (`U18/U19`) first — static electricity from fingers frequently kills the 4051s while sparing POKEY!
- 2. SIO Disk/FujiNet Transfers Fail (`BOOT ERROR` or No SIO Beep): POKEY pins 31, 32, 34, 38 handle serial SIO Data In/Out and Clock. Check the protection diodes/capacitor arrays (`CA3086` / discrete diodes) behind the 13-pin SIO port if hot-plugging an SIO device killed serial I/O.
- 3. Missing Sound Channels (While GTIA Keyclick Still Works!): Remember that the 800XL/XE mixes the GTIA `CONSOL` keyclick into the audio path separately from POKEY Pin 37 (`AUDIO`)!
- Modern POKEY Replacements: Original `CO12294` chips are expensive, but modern FPGA/CPLD drop-ins like PokeyMAX (which supports full Keyboard, Paddle pots, SIO, and Stereo/Quad POKEY + Covox!) work in every 400/800/XL/XE!
MMU (`CO61618`), FREDDIE & XL/XE Mylar Restoration
Checking custom glue logic and restoring oxidised Mitsumi Mylar keyboard ribbons.
- Replacing a Dead XL/XE MMU (`CO61618` — 20-Pin DIP): The original PAL16L8 MMU (`U3` on 800XL, `U21` on XE) runs warm and occasionally fails, causing a solid black or red screen. You can program a standard Lattice `GAL16V8B` (15ns) with the official Atari `CO61618` JEDEC file as a 100% drop-in replacement! (On a 130XE, the 16-pin `CO25953` EMMU can also be replaced with a `GAL16V8` using a 20-to-16 pin adapter or `Ultimate 1MB` upgrade).
- 800XL / 65XE / 130XE Mylar Keyboard Ribbon Fix:
- Never use harsh acetone on the flexible green/clear Mylar ribbon tail — it dissolves the conductive silver ink!
- Lightly buff the dark oxidised silver fingers at the tip of the Mylar tail with a soft white vinyl pencil eraser until bright silver returns, wipe dust away with a dry cloth, and clean inside the 24-pin PCB connector with DeoxIT D5.
- If traces have cracked at the fold, drop-in newly manufactured replacement Mylar membranes are readily available for both Mitsumi 800XLs and 65XE/130XEs.
5-Pin DIN Monitor (800XL Chroma Fix & UAV), 13-Pin SIO & PBI/ECI Pinouts
Why a stock Atari 800XL outputs Black & White on an S-Video cable (and the 1-wire fix!), plus SIO FujiNet/SDrive wiring.
5-Pin DIN Monitor Port & The 800XL Missing Chroma Fix DIN 180° • C64 S-Video Compatible!
The Atari 800, 800XL, 65XE, and 130XE use a 5-pin 180° DIN `MONITOR` socket with the exact same pinout as the 5-pin/8-pin Commodore 64 S-Video/Composite cable! However, on the Atari 800XL ONLY, Atari left Pin 5 (`CHROMA`) disconnected at the factory — meaning a C64 S-Video cable gives a razor-sharp Black & White picture on an un-modified 800XL!
| DIN-5 Pin | Atari Signal | RCA / S-Video Target | 800XL vs 130XE Status |
|---|---|---|---|
| Pin 1 | Luminance + Sync (Y) | S-Video Y (Pin 3) | Connected on 800, 800XL, 65XE, 130XE |
| Pin 2 | GND (0 V Shield) | Video & Audio Ground | Connected on all models |
| Pin 3 | Audio Out (Mono) | White/Red RCA Audio | Connected on all models (POKEY + GTIA Click) |
| Pin 4 | Composite Video Out | Yellow RCA Video | Connected on all models |
| Pin 5 | Chrominance (C) | S-Video C (Pin 4) | Connected on 800 & XE; DISCONNECTED on stock 800XL! (Note: absent on un-modded 600XL/1200XL) |
How to Enable S-Video Chroma on an Atari 800XL (10-Minute Mod!):
1. Locate the junction of resistor `R67` and `R68` (or inductor `L7` / capacitor `C54`) in the chroma path on the left side of the 800XL PCB.
2. Solder a 75 Ω–100 Ω resistor in series with a 470 pF–10 nF ceramic capacitor (or direct wire through the empty `R67`/chroma pad on late revisions) to Pin 5 of the 5-pin Monitor DIN socket (`J2`)!
3. Also clip out capacitor `C56` (an excessive low-pass filter cap on the Luma line) for an instant jump in 800XL S-Video sharpness — or drop a UAV (Ultimate Atari Video) board straight into the `CD4050` (`U16`/`U14`) hex-buffer socket for studio-grade S-Video and Composite!
13-Pin SIO (Serial I/O) Bus Pinout FujiNet / SDrive-MAX / 1050
Joe Decuir's daisy-chained 19,200–125,000 baud intelligent serial bus (the direct ancestor of USB!). Viewed looking at the rear female 13-pin trapezoidal SIO socket on the Atari (Top row = Odd pins 1, 3, 5, 7, 9, 11, 13 left-to-right; Bottom row = Even pins 2, 4, 6, 8, 10, 12 left-to-right):
| Top Odd Pin | SIO Signal | Bottom Even Pin | SIO Signal |
|---|---|---|---|
| Pin 1 | CLOCK IN (to Atari) | Pin 2 | CLOCK OUT (from Atari) |
| Pin 3 | DATA IN (to Atari, Pin 38 POKEY) | Pin 4 | GND (0 V Digital Ground) |
| Pin 5 | DATA OUT (from Atari, Pin 32 POKEY) | Pin 6 | GND (0 V Shield Ground) |
| Pin 7 | /COMMAND (from PIA CB2 Pin 19!) | Pin 8 | MOTOR CONTROL (Cassette 410/1010) |
| Pin 9 | /PROCEED (to PIA CA1 Pin 40) | Pin 10 | +5 V DC / READY (~50–300 mA max!) |
| Pin 11 | AUDIO IN (External Tape Audio to TV) | Pin 12 | +12 V DC (400/800 ONLY! NC on XL/XE!) |
| Pin 13 | /INTERRUPT (to PIA CB1 Pin 18) | — | — |
SIO `/COMMAND` (Pin 7) Troubleshooting: While `DATA IN` (Pin 3) and `DATA OUT` (Pin 5) go to POKEY, the `/COMMAND` frame strobe on Pin 7 comes from the 6520 PIA (`CB2`, Pin 19)! If keyboards and sound work (POKEY OK) and joysticks work, but a 1050 drive or FujiNet never responds to disk requests at all, check PIA Pin 19 (`CB2`)!
PBI (50-Pin XL) & ECI (14-Pin + Cart XE) Expansion Buses
Both the 600XL/800XL's 50-pin rear PBI edge and the 130XE/late-65XE's 14-pin ECI port (adjacent to the 30-pin cartridge slot) expose the full unbuffered 6502C address/data bus, `/EXTSEL` (to override internal RAM), `/MPD` (Math Pack Disable), and `/RST` — used today by plug-in AVGCart, SIDE3, Sys-Check V2.2, and 1MB RAM320XL expansions!
Custom Silicon & ROM / EPROM Reference
Interactive IC Pinout Finder cards plus Atari `CO`-number cross-references and 28-pin JEDEC OS/BASIC Rev C upgrades.
SALLY 6502C (`CO14806`)
1.79 MHz (NTSC) / 1.77 MHz (PAL) 6502 processor modified with Pin 35 (`/HALT`) tri-state DMA pause input.
View 6502 Family Pinout →6520 / 6821 PIA
Mapped at `$D300–$D303`: Port A = Joystick Ports 1 & 2; Port B = XL/XE ROM/RAM Banking (`$D301`); `CB2` = SIO `/COMMAND`.
View PIA Pinout →4164 / 4464 DRAM
Single-rail +5 V DRAMs in the 800XL (8× 4164) and 65XE/130XE (8/16× 4164 or 2/4× 4464).
View Pinout →4116 DRAM (16K×1)
Triple-rail (−5 V, +12 V, +5 V) DRAMs used on Atari 400 and Atari 800 16 KB RAM boards.
View Pinout →Atari Custom Silicon `CO` Part Number Cross-Reference
| Chip | NTSC Part Number | PAL Part Number | Key Pins & Notes |
|---|---|---|---|
| SALLY (6502C) | CO14806 / CO14806-12 (Both NTSC & PAL) |
Differs from standard 6502 on Pin 35 (`/HALT` input) and Pin 3 (`Φ1` out), Pin 37 (`Φ0` in), Pin 39 (`Φ2` out). | |
| ANTIC (Display DMA) | CO12296 (1979)CO21697 (XL/XE, 7-bit refresh) |
CO14887 (Early)CO21698 (XL/XE PAL, 50Hz) |
Generates 240/262 (NTSC) vs 312 (PAL) scanlines. `CO21697` / `CO21698` adds bit `RNMI` / 8th refresh line for 64K DRAMs. |
| GTIA (Graphics/Colour) | CO14805 |
CO14889 (PAL)CO20120 (SECAM) |
Outputs Luminance bits `LUM0–LUM3` (Pins 22–25), Color phase `COL` (Pin 21), `CSYNC` (Pin 27), and Console speaker (Pin 15). |
| POKEY (Sound/I-O) | CO12294 / CO12294B (Both NTSC & PAL) |
Pin 37 = `AUDIO OUT`, Pins 10–15 = `K0–K5`, Pins 31/32/34/38 = `SIO`. | |
| FREDDIE (XE / Late XL) | CO61922 / CO61991 (DIP-40) |
DRAM multiplexer & clock divider on 65XE, 130XE, and XEGS. | |
XL / XE OS (`16KB`) & Atari BASIC Rev C (`8KB`) EPROM Guide
Unlike the 24-pin 1200XL, the 600XL, 800XL, 65XE, and 130XE use standard 28-pin JEDEC sockets for the 16 KB OS ROM (and a 24-pin 2364 socket for the 8 KB BASIC ROM):
| Socket | Original Part # | Direct EPROM Drop-In & Upgrade Advice |
|---|---|---|
| XL/XE OS ROM (`16KB`) (`U5` on 800XL; `U4` on XE) |
CO61598B (Rev 2) |
27C128 (16 KB, 28-Pin) is a 100% Direct Drop-In! Or use a 27C256 / 27C512 with toggle switches on Pin 27 (`A14`) and Pin 1 (`A15`) to switch between stock XL/XE OS, QMEG OS, Omnimon!, and a High-Speed SIO / 800-Translator OS! |
| Atari BASIC ROM (`8KB`) (`U4` on 800XL; `U5` on XE) |
CO60302A (Rev B — Buggy!)CO24947A (Rev C — Fixed!) |
Most 800XLs shipped with BASIC Rev B (`CO60302A`), which has a notorious memory-corruption bug that adds 16 bytes to your program every time you `SAVE` and locks up the machine! Check with PRINT PEEK(43234) (`96` = buggy Rev B; `234` = clean Rev C!). Replace `U4` with an original `CO24947A`, a 24-pin `MCM68766`, or a 2364-to-27C64 adapter burned with BASIC Rev C (or Altirra BASIC)! |
Resources & Further Reading
Blog posts, interactive bench tools, and essential Atari 8-bit hardware communities.
Smiggy's Atari & 6502 Posts
Bench Tools & Machine Hubs
- IC Pinout Finder — 6502, 6520/6821, 4164, 4116 & more
- Recap Planner — capacitor replacement guide
- Ohm's Law Calculator
- C64 Machine Hub — Commodore 64 reference
- C128 Machine Hub — C128, C128D & DCR reference
- SX-64 Machine Hub — Executive Portable C64 reference
- Amiga Machine Hub — A500/A600/A1200 reference
- Big-Box Amiga Hub — A1000, A2000, A3000 & A4000 reference
- Atari ST Hub — 520ST, 1040STFM & STE reference
- Apple IIe Hub — Unenhanced, Enhanced & Platinum reference
- BBC Micro Hub — Model B, B+ & Master 128 reference
- Acorn Atom & Electron Hub — Atom & Electron reference
- ZX Spectrum Hub — 16K/48K & +2/+3 reference
- Sinclair QL Hub — 68008, Microdrive & ULA reference
- Dragon 32/64 Hub — Dragon 32 & 64 reference
- Oric-1 & Atmos Hub — Oric 6502A & ULA reference
- Amstrad CPC 464 Hub — CPC 464 & Datacorder reference
- Amstrad CPC 6128 Hub — 128K & 3″ disc reference
- MSX Machine Hub — MSX1, MSX2, MSX2+ & Turbo R reference
- Osborne 1 & Kaypro II Hub — CP/M luggable reference
- VIC-20 Machine Hub — Commodore VIC-20 reference
External Atari 8-Bit Resources
- AtariAge 8-Bit Forum — the world's largest active Atari 400/800/XL/XE hardware and repair community
- AtariMania — comprehensive software, ROM, and hardware documentation database
- FujiNet Project — open-source Wi-Fi SIO network & disk/printer adapter for Atari 8-bit
- Atari 800XL / 130XE Field Service Manuals — official Atari diagnostic flowcharts and schematics