Atari 1040STE
 | |
| An Atari 1040STE with its mouse | |
| Specifications | |
|---|---|
| Manufacturer | Atari Corporation |
| Type | Home computer |
| Released | September 1989 (West Germany) |
| Discontinued | 1994 |
| Intro price | DM 1,598 (September 1989); US$699 with colour monitor (June 1990) |
| CPU | Motorola MC68000 at 8 MHz (68-pin PLCC) |
| Memory | 1 MB on four 30-pin SIMMs (SIPPs on very early boards); up to 4 MB |
| Storage | Internal 3.5-inch double-sided floppy drive; external floppy (14-pin DIN) and ACSI hard disk (DB-19) ports |
| Display | 320 × 200 (16 of 4096 colours), 640 × 200 (4 of 4096), 640 × 400 monochrome |
| Sound | Yamaha YM2149 PSG, plus 8-bit stereo DMA sound with LMC1992 volume and tone control |
| ROM | 256 KB TOS in two 128K × 8 ROMs |
| Power | Internal switching supply, +5 V 3 A and +12 V 0.9 A, 2 A fuse |
| OS / Firmware | TOS 1.06, then TOS 1.62 |
| Predecessor | Atari 1040STF |
The Atari 1040STE is the 1 MB model of the Atari STE (ST Enhanced). It keeps the ST's display modes and software compatibility and adds a 4096-colour palette, 8-bit stereo DMA sound, the BLiTTER graphics chip, two extra game controller ports, and SIMM memory sockets.[1][2] The 1040STE and the 512 KB Atari 520STE are covered by one service manual, and Atari gives the second bank of RAM as the only significant difference between them.[1]
Atari first announced an improved ST at a trade fair in Milan in September 1987. The STE was shown to the trade press at CeBIT in March 1989 and to the public at the Atari fair in Düsseldorf in August 1989, and the 1040STE was on sale in West Germany from September 1989. The 1040STE was built until Atari left the computer market in 1994; after Atari closed its Taiwan factory in mid-1991 the machines were made by EFA Corporation and Golden Horse Computers.[2]
Hardware
[edit | edit source]| Position | Device | Atari part number |
|---|---|---|
| U100 | MC68000 CPU, 68-pin PLCC (socketed) | C398061-001 |
| U101 | BLiTTER, 68-pin | C101643 |
| U102, U103 | TOS 1.62 ROMs, high and low (US set) | C301163-002, C301164-002 |
| U200, U201 | MC6850 ACIA (keyboard and MIDI) | C025985 |
| U202 | YM2149 sound generator | C025983 |
| U203 | MC68901 MFP | C025984 |
| U204, U205 | TL497A switching regulators | C070447 |
| U300 | DMA controller | C398739-001 |
| U301 | WD1772 floppy controller | C026028-002 |
| U400 | GSTMCU, 144-pin | C300589-001 |
| U401 | STE Shifter, 84-pin | C300588-001 |
| U502, U503 | DAC0802 digital-to-analogue converters | C398057-001 |
| U508 | LMC1992 volume and tone controller | C398058-001 |
| U600–U603 | 30-pin SIMM sockets | C398063-001 |
The GSTMCU combines the jobs of the ST's GLUE and memory controller: it divides the 16 MHz clock down to 8 MHz, 4 MHz and 500 kHz, generates the video timing, prioritises interrupts, decodes addresses, asserts bus error on illegal accesses, and drives the DRAM.[1] The Shifter holds the 16 palette registers, each with four bits for red, green and blue, which is where the 4096 colours come from.[1]
Two DMA chips were used. Early STEs have C025913-38, the part used in the STF, and later ones C398739-001, the part in Atari's parts list. The early combination is associated with corrupted writes to ACSI hard disks, known as "bad DMA"; Christian Zietz traced the fault to spurious bus-grant pulses from the GSTMCU during long-word accesses to the DMA chip.[3]
Memory
[edit | edit source]Each 512 KB bank is a pair of 8-bit SIMMs forming the 16-bit memory bus. Atari's rules are that all SIMMs must be the same size, 256 kbit and 1 Mbit SIMMs cannot be mixed, all should have the same access time of 150 ns or faster, and 9-bit SIMMs may be used with the ninth bit ignored. The memory controller can address up to 4 MB.[1] Atari's US parts list gives the 1 MB set as four SIMMs, each made of eight 256K × 1 DRAMs rated at 120 ns.[1] Very early boards used SIPP modules in place of SIMMs.[2]
Video and sound
[edit | edit source]The STE keeps the ST's three modes: 320 × 200 with 16 colours and 640 × 200 with 4 colours, each chosen from 4096, and 640 × 400 monochrome. The RGB output can be genlocked. The television modulator is fitted to every STE board except the French Peritel version.[1]
The YM2149 is clocked at 2 MHz and its three channels go to the monitor speaker. The DMA sound hardware fetches 8-bit samples during horizontal blanking and plays them in stereo or mono at about 50, 25, 12.5 or 6.25 kHz, through a switched low-pass filter, a fixed 16 kHz filter and the LMC1992 to the two RCA sockets on the back panel. The stereo signal is also mixed into the monitor audio.[1]
Ports
[edit | edit source]Atari's manual gives the back panel, left to right, as: RS232 (modem), printer, hard disk (ACSI), external floppy, television output, monitor, power switch, stereo audio out (right and left), mains input and reset button. The left side has the cartridge slot, the two MIDI sockets and the two new game controller ports; the right side has the floppy drive slot.[1] Atari's manual counts four joystick channels on the two game controller ports, which also take two pairs of paddles and a light gun or pen.[1]
Power supply
[edit | edit source]The internal switching supply provides +5 V and +12 V, with a 2 A fuse. Atari's instruction is to set it to 5.1 V. It is rated at 3 A at +5 V and 0.9 A at +12 V, with 33.5 W maximum input; typical load in the machine is 1.75 A at +5 V and 86 mA at +12 V, rising to 2.2 A and 90 mA during disk access.[1] The supply has overcurrent protection, so Atari notes that a blown fuse usually means a catastrophic failure such as a shorted primary. The US supply is assembly CA070059-003 ("PSU 110V STE USA/CAN"); the manual has no schematic or parts list for it.[1]
The negative rails are made on the main board. U204, a TL497A switching regulator, produces the ±12 V for the RS232 line drivers, and U205 produces −5 V for the audio section, heavily filtered to keep switching noise out of the sound.[1] Dead RS232 or noisy audio with a good +5 V rail points at these two circuits.
Operating system
[edit | edit source]The first STEs shipped with TOS 1.06, which was soon replaced by TOS 1.62 because of a serious bug. The German Atari museum dates TOS 1.06 to 1990 and TOS 1.62 to 1990–1994, and reports that some of the last machines may have had TOS 2.06.[2] The two ROMs are in sockets at U102 and U103.[1]
Documentation
[edit | edit source]- Atari 520STE/1040STE Field Service Manual: Atari's STe 520/1040 Computer Field Service Manual, C302481-001 Rev A, August 1991, with power supply ratings, theory of operation, the diagnostic cartridge and its error codes, disassembly, symptom checklist and parts list. The hosted copy is the 2017 edition retyped by jer/eightbitter, with redrawn schematics.[1]
Related pages
[edit | edit source]- Atari STE General Maintenance
- Atari STE Troubleshooting Guide
- Atari STE Capacitor Replacement Guide
- Atari 520STE
- Atari 1040ST
- Atari Mega STE
References
[edit | edit source]- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 Atari Corporation, Atari STe 520/1040 Computer Field Service Manual, part number C302481-001 Rev A, August 1991. Section 1 (models, case and panels, power supply, negative supplies), section 2 (theory of operation: GSTMCU, main memory, DMA, video Shifter, sound, DMA sound, game controller ports), section 7 (parts list, US assemblies CA400339-201, CA400340-111 and CA400329-101). Hosted on this wiki as File:520ste.pdf, a retyped edition "updated by jer/eightbitter, May 2017", not a scan of Atari's printing.
- ↑ 2.0 2.1 2.2 2.3 "Atari 520ST E / 1040ST E", atari-computermuseum.de (in German). Secondary source for the announcement, show and sale dates, prices, the end of production, the later manufacturers, the SIPP modules on early boards and the TOS versions.
- ↑ Christian Zietz, "A new Atari STE bad DMA investigation", CHZ-Soft (with the ThunderStorm team). Community source for the two DMA chip part numbers, the symptom (twelve bytes lost after the first 32 of a sector written to an ACSI disk) and the measured cause.