1541 - Technical Details

Data Sheet

 Medium       : 5.25" floppy disk, double density, 1-sided (48tpi)
 Recording Fmt: GCR
 Capacity     : 166kB (35 tracks, 17-21 sectors/track)
 Speed        : 400 bytes/sec
 Interface    : serial IEC bus, controlled by VIA #1
 CPU          : 6502 @ ~1MHz
 RAM          : 2kB SRAM
 ROM          : 2x8kB (1541), containing DOS 2.6
                1x16kB (1541c, 1541-II), slightly modified DOS 2.6
 Power supply : internal transformer (5V+12V) (1540 / 1541 / 1541c)
                external transformer (5V+12V) (1541-II)
 Extras       : external device address switches (1541-II)

PCB history

Component Locations

	1540050 REV C
7406	UB1
7414	UA1
Controller	UC1
CPU 6502	UC4
ROMs	UB3 & UB4
SRAM	UB2
VIA #1	UC3
VIA #2	UC2

Note: Locations have been verified with MY board revisions If your board differs in component location, please mail me!

Documentation

• 1541 Disk Drive User's Guide
• 1540/1541 Service Manual
  Addendum to manual
• 1541 ROM disassembly
• 1541 ROM addresses
• 1541 test/demo disk
• 1541 ROM images

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