Floppy Drive Replacement Hardware
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.
Gotek
Introduction
General concensus is that if you buy a Gotek, you need to put the FlashFloppy firmware on it, although the flashing procedure may depend on whether your Gotek has the older STM or the newer Artery processor. The currently used Artery chip is both faster and has many times the memory of the STM32.
Sources and models vary in quality. General concensus is that you should buy one from a vendor which uses the larger AT32F435. The makers of FlashFloppy also recommend avoiding the AT32F415, models which start with UFA (e.g. UFA1M44), models which end with DU26 or TU26 (e.g., SFR1M44-DU25), the SFRA619, and FDD-UD U144K’s. Also, models with the CH32F103 will not work.
Cabling can be an issue as well. You must use straight cables, not twisted cables. Radio Shack/OEM cables are missing some pins in the drive side connectors, most critically the side select line. PC cables split the motor enable into two signals so they are a problem also,.
Installing FlashFloppy on a Gotek
Download the latest version of the firmware from https://github.com/keirf/flashfloppy/wiki/Downloads
Follow the instructions at https://github.com/keirf/flashfloppy/wiki/Firmware-Programming
Note: You should regularly check for firmware updates. Instructions to update the firmware are found at https://github.com/keirf/flashfloppy/wiki/Firmware-Update
Once flashed, set S1 jumper to match the drive you want to use.
If you want to use a Gotek externally, it can only boot if you unplug the internal drive and connect it to the top connector
Creating images
Format a USB stick to FAT 32
So long as you are going to use HFE files, you do not need a config file. Of course, a config file will let you customize your experience, so you might want to do one anyway. Details about the FF.CFG configuration file can be found at https://github.com/keirf/FlashFloppy/wiki/FF.CFG-Configuration-File. In general, the configuration file lets you customize such things as whether to write protect images, emulated head settle/motor delay, startup image, sorting, button actions, display type, etc.
To convert from a DMK image to HFE you can use the HxC utility found at https://hxc2001.com/download/floppy_drive_emulator/HxCFloppyEmulator_soft.zip. You would select LOAD to import the DMK image, and then EXPORT to save it as a HFE file.
Sleds
There are myriad options for sleds and cases for a GoTek, and you should search to see which one you like the best. Some examples are:
- https://jaynewirth.wixsite.com/newsoft
- https://www.thingiverse.com/thing:6636000
- https://www.thingiverse.com/thing:2725715
- https://www.thingiverse.com/thing:2217061/files
- https://www.amazon.com/StarTech-com-3-5in-5-25in-Bracket-Adapter/dp/B000HLZXH2/ref=sr_1_4?crid=27GY16CEC4BKW&keywords=3.5%2B5.25%2Badapter&qid=1653265189&sprefix=3.5%2B5.25%2Caps%2C95&sr=8-4&th=1
- https://www.thingiverse.com/thing:6652604
Floppy-80 for a REAL Model III / 4NGA
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For those out there with a Model III or Model 4 (NGA), Patrick Bureau of Texas Tandy Restorations is selling a hardware board called the Floppy-80.
The Floppy-80 is designed to replace entirely internal drives and external drives with a single SD card. It cannot be used in conjunction with real floppy drives, but can be used in systems that do not have floppy controllers.
The Floppy-80 board plugs directly unto the motherboard 20 pin edge connector that normally be used to connect a flat ribbon cable to the floppy disk controller (and +5v from a molex) that will let you mount DMK disk images (or HFE as read-only) on the fly on drives :0 :1 :2 and :3 and use the images as if they were real diskettes inserted into your TRS-80. .ini files can be prepared to set the 4 drives to a preconfigured configuration.
One of the other main features/benefits of the Floppy-80 is that you can set up .INI files which populate the drives, and can switch between those .INI files on the fly. You can also designate an .INI file which will be the default.
A utility for use in the TRS-80 is included and allows for the following additional commands:
An example of the commands would be that if you type FDC MNT OS-M3-MULTIDOS-531.DMK 2 at your TRS-80 DOS prompt, the DMK file OS-M3-MULTIDOS-531.DMK will then be mounted as :2
The Floppy-80 supports the following DOS’s for Drive 0
Model 3
Model 4 NGA
The Floppy-80 board is sold both as a kit and fully assembled and tested – reach out to TexasTandyRestorations@gmail.com for info.
HxC Floppy Drive Replacement for a REAL Model I/III/4
The SDCard HxC Floppy Emulator designed by Jean-Francois 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
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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 https://github.com/calphool/TRS80MXS.