A downloadable tool

A replacement firmware for 128K Spectrums based on version 1.4 of the Derby development ROM.

Sky In-Home Service Ltd has kindly given its permission for the redistribution of its copyrighted material but retains that copyright.

Use of this software in unlicensed hardware is prohibited.

The Spectrum 128 was a Spanish machine commissioned by Investronica and launched in 1985. It shipped with a keypad that provided additional editing keys. The UK version got a simplified ROM and no keypad. Derby++ is an enhanced version of the ROM that shipped with the Spanish machine. It has the following features:

  • Fastest version of 128 BASIC.
  • All modes work with esxDOS on divIDE and divMMC.
  • Works with Multiface (128/3).
  • Supports 128 BASIC with Spectranet.
  • 48 mode ROM is 100% compatible with the original ROM (because it is the original ROM).
  • Holding down ENTER while selecting 128 BASIC is equivalent to Tape Loader (if used in a 32K ROM configuration hold down ENTER on power on or reset).
  • In a 32K ROM configuration, hold down BREAK on power on or reset to boot into 48 mode.
  • When CAPS LOCK is off, lower case text is tokenized.
  • When CAPS LOCK is on, SHIFT produces lower case text.
  • Will run software compiled with HiSoft BASIC 128  (although not the editor itself).
  • New mapping of extra editing keys.
  • Fully bug-fixed and optimized editor and BASIC.
  • Variables are persistent (not CLEARed when a program is RUN) in 128 BASIC.
  • The SPECTRUM command is replaced with the PALETTE command for ULAplus.
  • Default 16 color palette (enables mixing of any two colors).
  • PLAY command supports six channel AY (TurboSound).
  • TR-DOS menu.

It has the following features in common with the Spanish 128:

  • Full-screen string editor.
  • Running calculator (use from BASIC as if you were in the calculator option on the UK machine).
  • Five new direct commands.
  • PLAY command.
  • Use keywords as variables by entering them in lower or mixed case (when CAPS LOCK is on).
  • Use embedded control codes.
  • Set the INK and PAPER colors of the editor.
  • Much faster editor than the UK machine.

Install instructions

  • Loader option requires Spectranet or esxDOS (http://esxdos.org/. You should use the Dr Slump NMI browser (https://www.dropbox.com/s/yabd22iv15qd6xh/nmi_v0.0.15.zip?dl=0).
  • TR-DOS option requires esxDOS or BetaDisk.
  • Known issues:
    • You must enter at least one command (for example REM) in 128 BASIC before esxDOS will respond to dot commands.
    • In 128 BASIC you must enter esxDOS commands in lower case and ensure CAPS LOCK is enabled before pressing ENTER.
    • In 128 BASIC, to enter an esxDOS command at the start of the line you must prefix it with a colon (:).


DerbyPlusPlus.zip 94 kB

Development log