MB03+ Ultimate2 is a powerful, compact, next-generation ZX Spectrum interface that provides the functionality of a large number of hardware and system add-ons for the ZX Spectrum and compatible computers, in an all-in-one solution. The MB03+ is normally connected to the standard edge connector of any ZX Spectrum. It consists of modern circuitry with a fast FPGA chip and is fully compatible with the popular divMMC/SD and divIDE/CF interfaces. The Ultimate2 is 100% compatible with the older Ultimate model.

This is a non-profit, hobby-based development project. Please visit the eLeMeNt ZX, MB03+ Users Facebook Group. Read more MB03+ related articles, reviews and discussions on the forums Oldcomp.cz  and SpectrumComputing.co.uk. User support  is available on the Telegram: eLeMeNt User Forum.

Jan Kucera aka LMN128, author of the MB03+

Specifications :

• square shape 10x10cm board, connected to ZX edge socket in horizontal position

• powered by ZX Spectrum - no external power supply needed

• fully compatible with all ZX Spectrum models

• digital video and audio output to modern TVs or PC monitors, scan line display effects possible to mimic old good retro TV/CRT displays

• FPGA Xilinx Spartan7 - XC7S50 484pins, the main brain of the machine

• 16MBytes SRAM + 2MBytes Fast SRAM + 1MBytes FLASH + FRAM 8KB (system info, bios config); every RAM is expandable through expansion sockets

• accurate RealTimeClock (DS3234) with SRAM and emulation of older RTC 72421 (for esxDOS SYS driver)

• CompactFlash(IDE) card and 2x microSD cards sockets

• Wi-Fi module ESP8266, UART connection, 8x8 LED matrix display

• 2x USB ports, one for a PC-link, second for K-Mouse or PC keyboard (PS/2 compatible)

• Custom ROMs of 16KB and 64KB (DerbyPro), diagnostic and test ROMs, possibility to use patched ROMs, e.g. 64char ROM

• tremendous sound capabilities: 3xAY/YM, TurboSound or TurboSound FM (2xYM2203), SAA1099, SounDrive/Stereo Covox/Specdrum, SID (C64) and General Sound (28 MHz Z80-CPU, 16KB ROM, 2MB RAM, 4x 8bit channels)

• Z80 DMA and FastDMA, SafeNMI, SaveINT, I/O port-based LIFO stack and other internal hardware enhancements

• two internal expansions sockets, FADI compliant

• Ultimate firmware - a quick boot and SetUp with easy hardware settings and switchable configurations

• divSD, divIDE, divMMC, Z-Controller SD, esxDOS (UnoDOS) compatible, MB02+, MBIDE and BSDOS308 compatible, 

• TRDOS emulation via esxDOS, compatible with other systems like divide+ (G+DOS)  and MDOS3 in divIDE mode or Residos in the MB02+ mode

• TIMEX Hi-Color and Hi-Res graphics modes and ZX-Uno's Radastan graphics, ULAplus and TrueColour palettes

• two VideoRAMs also on 48K Spectrums, three levels of non-flickering GigaScreen, Klayer mode with a transparence colour

• attribute-based 512*192 HiResColour and HiResindeXedColour modes

• HGFX - ZX Planar, HAM and FILL modes, resolutions:  256*192, 512*192, 512*384 and 720*546, up to 256 colours from 16777216

Visions and possibilities for another SW coders and HW designers:

• advanced firmware extensions, in cooperation with Lordcoxis - a powerfull esxDOS/NG

• a great potential for many hardware extensions, e.g. better LED displays, bigger RAM and flashRAM, more joystick ports or smaller and compact versions of older interfaces , such as printer or floppy IFs (Betadisk, Didaktik D40/D80, Plus D and Disciple, Diskface, Opus Discovery, MB02+)