Editing Atari 520STE/1040STE Field Service Manual

The '''Atari STe 520/1040 Computer Field Service Manual''' is Atari Corporation's own field service manual for the [[Atari 520STE]] and [[Atari 1040STE]], '''part number C302481-001 Rev A''', '''August 1991'''. 81 pages, with a text layer and searchable. Copyright Atari Corporation 1991, Sunnyvale, California.

== Contents ==

* '''1 Introduction''' — overview 1, main components 1, case design 1, '''power supply 3''', '''negative supplies 3'''
* '''2 Theory of operation''' — 4: main system, audio/video subsystem, input/output subsystems, MPU, '''GSTMCU''', main memory, DMA, multi-function peripheral control, digitised sound, genlock, I/O subsystems 11, '''system startup 21''', '''system errors 22'''
* '''3 Testing''' — 24: test configuration 25, '''troubleshooting a dead unit 25''', diagnostic cartridge 26, power-up sequence 26, test menu 28, then RAM, ROM, colour, keyboard, MIDI, RS232, audio, timing, DMA, floppy, printer and joystick port, monochrome monitor, hard disk write/read and BLiTTER tests, ending with '''error codes (quick reference) 38'''
* '''4 Disassembly/assembly''' — 43
* '''5 Symptom checklist''' — 45: display, disk drive, keyboard, MIDI, RS232, printer port, hard disk port and DMA sound problems
* '''6 Diagnostic flowcharts''' — 47, with replacement procedures and IC handling 47
* '''7 Parts list''' — 52
* '''8 Glossary''' — 56
* '''9 Schematics and silkscreens''' — 58

== What it settles ==

'''The power supply section (§1.3) gives figures a meter can check:'''

<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:75%;"
|+'''STE internal switching supply, from §1.3'''
! Item !! Atari's figure
|-
| Rails || '''+5&nbsp;V''' and '''+12&nbsp;V''', integral to the case
|-
| Fuse || '''2&nbsp;A'''
|-
| Adjustment || '''set to 5.1&nbsp;V'''
|-
| Rating || 3&nbsp;A at 5&nbsp;V, 0.9&nbsp;A at +12&nbsp;V; max power in '''33.5&nbsp;W'''
|-
| Typical in-system draw || 1.75&nbsp;A at 5&nbsp;V, 86&nbsp;mA at +12&nbsp;V
|-
| Maximum draw || 2.2&nbsp;A at +5&nbsp;V, 90&nbsp;mA at +12&nbsp;V, during disk access
|}

Atari adds a warning worth repeating: the supply has overcurrent protection, so '''if the fuse has blown, a catastrophic failure such as a shorted primary is likely''' — replacing the fuse alone is not the repair.

'''The negative supplies (§1.4) are generated on the motherboard, not in the PSU.''' Two small switching regulators of the TL497 type do it: '''U204''' produces the '''±12&nbsp;V''' for the RS232 line drivers, and '''U205''' produces '''&minus;5&nbsp;V''' for the audio section, heavily filtered to keep switching noise out of the audio output. A machine with dead RS232 or noisy audio and a healthy +5&nbsp;V rail should be checked here before anything else.

'''Section 7 is a real parts list with designators.''' It is organised by assembly number — CA400338-201, CA400339-201, SE400340-111, CA400366-001, CA400495-001, CA400329-101 — and within each gives Atari part number, description and location/quantity. It names the ICs by type and position (U100 68000 PLCC, U101 BLiTTER, U300 DMA controller, U301 1772 FDC, U202 YM-2149, U203 68901 MFP, U200/U201 6850 ACIA, U204/U205 TL497A, U401 STE shifter, U102/U103 the TOS 1.62 ROMs, U600&ndash;U603 the SIMMs) '''and lists the electrolytic capacitors with value, voltage and designator''' — for example the 47&nbsp;µF, 100&nbsp;µF, 470&nbsp;µF and 10&nbsp;µF axial and radial parts and the 15&nbsp;µF tantalums, each against its C-number. This is the component-level source for the STE mainboard.

== What this manual does not contain ==

* '''No power supply internals.''' The supply appears in the parts list as a single assembly — CA070059-003, "ASSY PSU 110V STE USA/CAN" — so the ratings above are all Atari published about it. There is no PSU schematic and no PSU bill of materials.
* '''No monitor coverage''' — the SM124 and SC1224 are named as trademarks but not serviced here.
* '''No coverage of the ST, STF, STFM, Mega ST, Mega STE or TT.''' For the earlier machines see [[Atari 520ST and 1040ST Computer Field Service Manual]].
* Atari's own caveat, printed on the copyright page: part numbers are for reference only, and only parts on the then-current dealer parts lists were available.

== Pages that cite this document ==

* [[Atari 520STE]] · [[Atari 1040STE]]

<pdf> File:520ste.pdf </pdf>

Download here: [[:File:520ste.pdf|520ste.pdf]]

[[Category:Atari Service Manuals]]
[[Category:Service Manuals]]