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 main page is here. The documentation can be found here and the changelog can be found here.

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

Eric Rothfus has developed a hardware device called the SVD (Semi-Virtual Diskette) which is a device which emulates a floppy drive.

The SVD connects to the serial port of a PC and to the floppy drive cable on your TRS-80, download a floppy image to the SVD, and then boot that image on an actual TRS-80 as if that floppy was actually in the TRS-80’s drive.

The SVD is actually bi-directional, so you can also save from the TRS-80 onto the PC.

The SVD is based upon a PIC micro-controller along with some memory. It listens to the floppy control signals from the TRS-80 and generates the appropriate signals back, so the TRS-80 believes that it is attached to a real floppy drive. It attaches to a PC through a standard serial port, operating between 9600 and 115200 baud. Through programs running on your PC, you down/up-load the SVD and control its operation. The PC interface includes capability to read/write “standard” diskette formats.

Current features of the SVD are:

  • Up to three diskette images can be loaded at once (drive 0, 1, and 2) up to 256k
  • single-sided single density (SS SD)
  • double density (SS DD)
  • reading/booting the diskette image
  • writing the diskette image
  • LEDs for power, drive0/1/2, track0, and write
  • Supports Model I, III, 4, 4P and CoCo.

You can get more information on the main SVD page found at That site is VERY VERY detailed.

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