The 520 ST featured same hardware basis and same amount of memory as the 260 ST.
The main difference between them was the built-in ROM TOS operating system and GEM Graphics Interface. In fact, the Atari 520ST originally came with the OS on floppy as the OS was not completely finished. Very shortly afterward they came with the OS on 6 ROM chips (TOS 1.0).
These are the basic specifications for the Atari 520ST:
- CPU: Motorola 68000 @ 8 MHz
- RAM: 512 KB
- Sound: Yamaha YM2149F, three pulse wave channels and one white noise channel
- Disk Drive: Single-sided 3½” floppy disk drive. 360kb capacity (1040ST had double-sided drives which had a capacity of 720kb).
- Display: 60 Hz NTSC, 50 Hz PAL, 71.2 Hz monochrome:
Low Resolution – 320×200 (16 color), palette of 512 colors
Medium resolution – 640×200 (4 color), palette of 512 colors
High resolution – 640×400 (mono), monochrome
- Ports: RF out (on STM and STFM models, NTSC or PAL), MIDI in/out (with ‘out-thru’), RS-232 serial, Centronics parallel (printer), monitor (RGB or Composite Video color and monochrome, 13-pin DIN), external disk drive port (15-pin DIN), DMA port (ACSI port, Atari Computer System Interface) for hard disks and Atari Laser Printer (sharing RAM with computer system), joystick and mouse ports (DE-9 Atari pinout).
- Operating System: TOS (The Operating System) with the GEM user interface.
I have the Atari 520 STfm version of the computer, released in 1986. This version features a built-in floppy drive, RF modulator and power supply. The STfm includes a modulator allowing you to plug the computer into a TV, making it cheaper to buy.
Version – PAL Atari 520 STfm
Rating – Unboxed Including Manual
Condition – Hardware – 7/10 (Yellowed)
Accessories – AV Cable, Power cable
Paid – £221.60 (Cash Converters, Included Many Games)