Drive Replacement for a REAL Model I/III/4

This page covers the modern hardware which can be used to replace Floppy Drives in a real TRS-80.

HxC Floppy Drive Replacement for a REAL Model I/III/4

The SDCard HxC Floppy Emulator designed by Jean-François Del Nero, emulates a 34 pin floppy drive and treats DSK and DMK images which are stored on a SD card as actually floppy disks. To be clear, this product is designed to be mounted in/on an actual TRS-80, as a drive on the floppy cable.

It can emulate one or two drives, and disk images are mounted using the three buttons on the lower right, which are NEXT, SELECT/EJECT, and PREVIOUS. The filenames are shown on the LCD, which comes in a variety of colors.

Current features of the SDCard HxC Floppy Emulator are:

  • Modes Supported: Shugart and PC
  • Two floppy disk drives emulation
  • 5V +/- 10% standard power floppy connector input
  • 3 LEDs (“Power LED”,”Floppy access LED”,” SDCard access LED “)
  • 3 buttons (“Next”,”Select/Eject”,”Previous”)
  • 1 audio transducer
  • 2*16 chars Alphanumerical LCD (LCD and buttons can be put on an external front panel)
  • SD Card up to 2GB / SDHC Card supported up to 32GB
  • FAT32 supported. Subdirectory and long name file supported
  • Track mode based floppy emulator (Full track pre-encoded in the HFE image file)
  • Write support: ISO MFM 256/512/1024 Bytes sector write supported, ISO FM/SD 128/256/512/1024 Bytes sector write supported.
  • Bitrate support: 250/300Kbits/s (DD floppies), 500Kbits/s (HD floppies)
  • RPM support: 300, 360
  • Tracks / Side support: Up to 256 tracks per floppy, 1 or 2 sides.

The documentation can be found here and the changelog can be found here.

MXS (TRS-80 Modular eXpansion System) for the Model I

The TRS-80 Modular eXpansion System (MXS) designed by Jay Rounceville, consists of up to four modules set up as a stackable set, starting with the base module which will give you a 32K and supplies the power that the other boards use. On top of this you can add the floppy drive emulator module. Other modules include a Texas Instruments video/graphics board and/or a WIFI board.

Schematics and overview can be found at

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