ROM Memory Expansion

The “operating system” of the ZX80, ZX81 and TS 1000 computers was contained in a special read-only memory (ROM) chip inside the computer. In all three, that chip was often in a socket, which made it easy to replace with another ROM.

Hardware that attached to the expansion port also supported ROMs, giving users a lot of opportunity to expand their systems.

For TS 2068 users, the cartridge slot allowed for ROM images to be delivered as cartridges.

Name Description Computers
16K EPROM Vaporware announced as coming soon in the Sync v3 n1 advertisement. Timex/Sinclair 1000
2068 EXROM Revision Edited version of the 2068 EXROM, likely to correct some issues with the original EXROM. Timex/Sinclair 2068, Downloadable
2068 Programmer's Cartridge (AROS) Toolkit 24K program has many built-in features (including tri-base arithmetic) and printer drivers. Available on tape ($9.95) or EPROM ($39.95) Timex/Sinclair 2068, Downloadable
2068 Spectrum ROM Untested EPROM. There is a one byte difference at 6Dh in the NMI routine. The original Spectrum ROM has 20h at this location; this ROM has 28h. Timex/Sinclair 2068, Downloadable
2716 * 4 EPROM Reader Map its 2716 EPROMs anywhere in the 64K memory. Board is intended to be used as a “cartridge” for storing Sinclair programs on EPROM. It can be used to store machine code tools in the 8-16K block. Timex/Sinclair 1000
2764 * 2 EPROM Reader Board is capable of mapping either of its 2764 EPROMs anywhere in the 64K map in 8K blocks. Board is intended to be used as a “cartridge” for storing Sinclair programs on EPROM. It can be used to store machine code tools in the 8-16K block. Timex/Sinclair 1000
2K "Toolkit" EPROM Works with EPROM-READ card. 2716 EPROM operating in 8192-10239 part of memory-map. Programmed with Breakout, Life, and Toolkit (renumber, including GOTO and GOSUB; READ, DATA, RESTORE; BLOCK-FILL, of screen; block delete, part of program; size, of program; free memory and others). Timex/Sinclair 1000
4K Toolkit 16 utilities that are relocatable to wherever you can execute machine code, on EPROM. Tape version available from Tom Woods. Timex/Sinclair 1000, Downloadable
6502 Graphic Hardware Emulator All features of 6502 Software Emulator plus graphic display of 6502 hardware status. Timex/Sinclair 1000
6502 Software Emulator Learn 6502 machine language on your computer. Develop 6502 programs. Timex/Sinclair 1000
8K BASIC ROM The new BASIC allows the use of floating point arithmetic to nine digit accuracy, and contains log and trig functions with inverses. This ROM facilitates improved graphics, and contains 37 new functions including DRAW, DATA, ARCSIN, VAL, and SCROLL. The plug-in conversion includes a new keyboard template and a supplementary manual. Sinclair ZX80
8K BASIC ROM Upgrade ZX-80 compatible 4K ROM to ZX-81 compatible 8K ROM. The MicroAce scrambled several data lines, so it requires an equally scrambled ROM. MicroAce
8K EPROM Board Allows up to 8K of EPROM or RAM in 2K blocks to be added in the 8-16K ZX81 memory map. Supplied with EPROM I which contains 40 toolkit type routines, including scroll up/down/left/right, free memory, renumber program length. Timex/Sinclair 1000
ASCII Communications Firmware EPROM (2716) used with the CAI/O board. Converts Sinclair code to ASCII code, allowing the TS1000 to communicate with other computers and serial devices. Supports BAUD rates of 110 to 9600. Timex/Sinclair 1000
Assembler Code and edit a source program in the Z80 language and assemble it into machine code. Editor mode allows you to code directly in the right format, manipulate individual lines and control the exact placing of source and machine code. Routines may be merged or listed. Assembler mode handles all standard Z80 mnemonics, numbers in Timex/Sinclair 1000
ASZMIC ROM Plug-in replacement ROM for Sinclair Basic. Redefines hardware and transforms it into an assembly language programming unit. ROM appears at 3000h-4000h. Offers: According to Chris Johnson, the developer, “We had a lot of TS1000 customers for ASZMIC, since it was mentioned in Sol Libes’ column in Byte magazine.“ The name is an abbreviation of ”Assembler Timex/Sinclair 1000, Downloadable
Character Cartridge ROM holding 3 character sets. Upper/lower case, graphics and math/electronics. Supports custom, user-defined character set. Timex/Sinclair 1000
Corrected EPROM EPROM to correct bugs in the 2068 ROM. Timex/Sinclair 2068
Custom Programmed 2K ROMs Service to store BASIC or machine language programs in EPROMs. For use with Professional Electronics’ printer interface board. Timex/Sinclair 1000
Debugged EXROM Ray Kingsley’s fixes to the Timex EXROM, available as a 2764 EPROM. Timex/Sinclair 2068
Disassembler 4K ROM 2716/2732 EPROM compatible. Timex/Sinclair 1000
DROM DROM stands for Development Read Only Memory. This module can have up to 8K of RAM, via plug-on 2K RAM chips. The memory is backed by rechargeable battery for non-volatile storage of programs and data. Behaves as normal read/write RAM when the computer is in use. Individual 2K blocks can be protected against overwriting. DROM Timex/Sinclair 1000
EPROM Board Board containing ‘SCOPE‘ and ‘FFT‘ programs on four 2716 EPROMs in 8-16K memory space, on the Hunter board. Timex/Sinclair 1000
EPROM Cartridge Kit Uncased board holds one 2716, 2732 or 2764, mapped 0-16K. Jumper selectable. Kit includes board, decoder chip, 28 pin socket, edge connector, tailpiece, small parts, and instructions. Timex/Sinclair 1000
EPROM Cartridge Kit Kit includes all parts necessary to build a plug in cartridge that will accept 2716, 2732, or 2764 EPROMs. Board may be memory mapped in 4K or 8K increments anywhere from 0-16K. Board accepts one EPROM and the memory mapping is jumper selectable. Timex/Sinclair 1000
EPROM Programmer Store programs in EPROM. Module holds four 2716 EPROMs for 8K of ROM in 8K-16K region. Timex/Sinclair 1000
EPROM Programmer/Reader Supports two 4K 2732 EPROMs in the 8-16K slot. Housed in slim plastic case with ribbon connector and expansion port making it compatible with RAM packs, printers, etc. Uses zero insertion force sockets for programs that load in seconds instead of minutes. Timex/Sinclair 1000
EPROM-READ Card Accepts 2K 2716 and 2516 EPROMS. Operates in the 8192-10239 section of the memory map. Fits between the computer and RAM pack. With modification, it is compatible with certain other types of RAM. Timex/Sinclair 1000
Frequency Analysis 'FFT' Fast Fourier Transform on EPROM in 4K of Z80 code. 256 points of magnitude and phase data calculated in one second. Can be used as a subroutine with the ‘SCOPE‘ to display frequencies up to 75khz. Timex/Sinclair 1000
Improved ROM for TS1000 Debugged/improved LPRINT, CLS, SCROLL, DIM and more. Full display file, SCROLL/CLS work properly, LPRINT small numbers (.0001), DIM very large single strings (DIM A$(47000)) in 64K and a few other changes incorporated. For the 16K TS1000, TS1500 or ZX81. Sinclair ZX81, Timex/Sinclair 1000, Timex/Sinclair 1500
Memocalc Spreadsheet analysis to assist with reports and financial forecasts. Performs complex number crunching routines with ease. Tables up to 7000 numbers, 250 rows or 99 columns with 64K. Calculate command reevaluates and displays the information. Timex/Sinclair 1000
Memotext Brings commercial standards of text editing to the Sinclair. Text is arranged in 32 character lines for the screen with comprehensive editing facilities. On output, the user chooses the line length required for printing and the system does the rest. When used with the Memopak Centronics interface, the word processor can print 80 character lines, Timex/Sinclair 1000
OS 64 Cartridge OS-64 is a ROM that supports the Timex/Sinclair’s 64-column mode. It is fully compatible with 32 column commands and functions. The original Zebra manual is available on archive.org. OS-64 is supplied on cartridge. Insert in the TS2068’s cartridge slot (with the power turned off), then turn your computer on. The boot screen will be black Timex/Sinclair 2068, Downloadable
PC8300 Timex ROM Custom adaptation of the Timex/Sinclair 1000 ROM for the Lambda 8300 computer. Adapted by Fred Nachbaur, the replacement EPROM came in a 2764, a 28-pin device (several additional pins were necessary for programming EPROMs). The PC8300 ROM was a 24-pin 8K ROM. In order to fit the replacement EPROM to the PC8300, several pins were Lambda 8300, Downloadable
Pluri-Forth Pluri-Forth is both an operating system and a programming language, replacing the Sinclair ROM entirely. FORTH programs were compiled and ran about 10 times faster than interpreter BASIC. Pluri-Forth offered multitasking, a feature not available in Basic. When used with the Sinclair ROM, the channel 2/3 switch is wired to the Pluri-Forth board to select Timex/Sinclair 1000, Downloadable
QL Internal ROM Board Allows you to put your favorite ROM version (JM , JS, JSU, MGUS, MGUK , etc.) on an EPROM. This will lower power consumption by the QL by about 20% & drop the internal heat by close to 50 degrees Fahrenheit. Sinclair QL
RB-ZX ROM Board Modular interface that maps a ROM to several locations in memory. Sinclair ZX81, Timex/Sinclair 1000
ROM Board for TS1000 & ZX81 Automatically sets system RAMTOP, up to 64K, automatically boots AERCO DISC system on reset. Timex/Sinclair 1000
ROM-81 Store useful routines and commonly used information in EPROM. Accepts either 2716 or 2732 EPROMs to allow up to 8K of memory in 2K byte increments. Separate 2K and 4K decoding is link selectable. Mapped to the 8-16K area in the TS 1000 memory map. Timex/Sinclair 1000
Serial Printer Firmware EPROM is contained in the ASCII firmware. When used with the CAI/O board, allows the user to communicate with other computers and with serial devices such as printers and teletypes. Supports BAUD rates of 110 to 9600. Timex/Sinclair 1000
Softbox Cartridges Solid state cartridges that plug directly onto the Softbox (up to 4 at a time) or onto the back of the computer (1 at a time). With control cartridges, you can perform different automatic functions. Cartridges eliminate waiting for cassette-based programs to load. Timex/Sinclair 1000
Spectrum B ROMs On EPROM, bug corrected with additional character set. Timex/Sinclair 2068
Spectrum ROM Timex/Sinclair 2068
Speedscreen ROM for ROMport. Sinclair QL
Super ROM Board Built-in printer interface, EPROM burner and autostart ROM. Timex/Sinclair 1000
Toolkit Uses up to four 2K EPROMs. Address space after on-board ROM. Allows calling TOOLKIT-held routines with USR function. Several TOOLKIT modules can be used under MINIMAP. A module in the BASICare Modular Expansion System. Timex/Sinclair 1000
TS 1510 Command Cartridge Player Cartridge adapter for the TS 1000 and TS 1500 computers. Includes reset switch. Loaded Timex Command Cartridges instantly on the TS 1500 and with a USR call on the TS 1000. Four cartridges were listed in the Timex 1983 Winter Catalog. Timex/Sinclair 1000, Timex/Sinclair 1500
ts2068cart This board allows many 28-pin EPROMs, EEPROMs and mask ROMs to be used in the cartridge slot of the Timex Sinclair 2068 computer. The installed memory may be mapped into any or all of the 8k banks of the dock space. Write access is supported for EEPROM memories. You can learn more about this board Timex/Sinclair 2068
ZX80 ROM switch Use your 4K or 8K software at the flick of a switch. Optional add-ons include keyboard beeper and cassette load processor. Sinclair ZX80
Scroll to Top