This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

• If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original.
• You may not use the material for commercial purposes.
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Original Design by Dandare, mad3001 and OverClk

ZX Dandanator MTD & MTD_TH PCB's are designs by MerlinKV

This project is a mix of the ZX Dandanator Mini! & the Multiply add-on.

• This project was made for retro community, individuals or forums, and NOT FOR COMMERCIAL PURPOSES.
• Its commercial sale on eBay, auction sites or shops (online or not) is PROHIBITED.
• So only retro hardware forums and individual people with non profit intentions can build this project.

• If you wish to sell small quantities of this interface in a physical or online store, you must first contact me to request permission. The ban on selling it on eBay or auction sites remains in effect.

I take no responsibiltiy for any damage to any equipment that results from the use of this board. USE AT YOUR OWN RISK!

• 02-06-2025

  • Published versions 2.0, 2.0s & 2.0Ds
  • mSD slot has been changed to Push-Push
  • Now it's possible to use a Joystick with two fire buttons (e.g. shooting and throwing grenades) in games that support it or are patched to do so.
  • In order to use the second fire button, you must program the Arduino Nano with the firmware published in the 'Firmware' folder or with the included new ROM Generator:
    • To programm the Arduino Nano hex files the best option is to use AVRDUDDESS: https://github.com/ZakKemble/AVRDUDESS/releases/tag/v2.18
    • A new ROM Generator jar file is included (ZX Dandanator MTD 10.4.3.jar) in the Firmware folder. This ROM Generator can be used to "Upgrade Multiply" with the two Joystick buttons activated.
    • The stock firmware also works and can be programmed from the original ROM Generator, but in this case only one fire button will work.
  • 2.0 PCB's notes:
    • 2.0s (small) is a two layers PCB
    • 2.0Ds (small) is a four layers PCB with EDGE connector on the back
    • Slide Switches: 5 pin, 3mm, SPDT
    • mSD slot: Hirose DM3AT-SF-PEJM5
  • Included two example patched games (thanks to @mad3001).
  • Interactive BOM ZX Dandanator MTD_2_0
  • Interactive BOM ZX Dandanator MTD_2_0Ds
  • Interactive BOM ZX Dandanator MTD_2_0s

• 11-09-2024

  • Two versions of the 1.7 board (different mSD footprints).
    • 1.7 -> SD Push-Push / mSD Push-Pull
    • 1.7b -> SD Push-Push / mSD Push-Push
  • Added STL 3D Printer files (designed for Arduino on Socket)

• 10-08-2024

  • Version 1.6 updated to 1.7 - All working fine
  • Version 1.5s updated to 1.7s - All working fine
  • Users of the the latest revisions of 1.6 and 1.5s:
    • A bug in the design prevents detection of the Multiply
    • The solution is very simple: Just do not solder R3 and D2. Then connect the D9 pin of the Arduino Nano to +5v. This can be done on the Arduino nano itself by simply connecting a small wire between both points.

• 09-05-2024

  • Versions 1.5s and 1.6 updated. Version 1.5 deleted.

• 09-05-2024

  • Reworking the 1.5s & 1.6 versions, they will be available soon.

• 06-04-2024

  • Schematics, PCB's and Gerbers of versions 1.5s & 1.6 successfully ported to KiCad 8.0.1

• 02-04-2024

  • v1.5 & v1.5s: Fixed some bugs. The two boards has been rerouted.
  • Added a new version 1.6 (to be tested) with SD Card detection. If you have one mSD inserted and by mistake you insert an SD, the mSD will be disabled.

• 31-03-2024

  • mSD socket moved to the back side of the PCB.
  • Now you can solder two sockets (SD and mSD) but, remember, they cannot be used simultaneously. Use only an SD or mSD when using the interface.

• 29-03-2024

  • Fixed a mistake on U10 and SD/mSD 3.3v power supply
  • If you have the first boards of version 1.5 or 1.5s you must solder a wire between pin 1 and pin 8 of U10.
  • Now, everything is working fine.

• 04-01-2024 - Added two new versions of the interface.

  • Version 1.5 is full lenght and have a rear ZX Spectrum Edge connector.
  • Version 1.5s is smaller with only one mSD socket and without rear ZX Spectrum Edge connector.
  • Most of the componentes are now SMD/SMT.
  • GAL replaced by 74HCT IC's series.
  • Added connector to allow the programming of the PIC (if needed).
  • Now you can programm the Arduino Nano directly (you don't need to disable the joystick).
  • Now you have only three switches: ROM SELECT, JOYSTIC ON-OFF & PAUSE.
  • Some users find the power LED light too bright. This has an easy solution by replacing R10 (680 Ohms) with one of a higher value, ie: 1K, 1K2, ...

• 31-12-2023 - Added a new preliminary scheme for replacing GAL with 74HCT IC series.

• 26-08-2023 - Added 3D Printer files (STL) for those who wants to put the arduino in a socket.

• I have made two different boards, one with a PIC in True Hole format, and second with the PIC in SMD format (these ones are cheap).

• Multiply upgradeable from ROMSet's creator. Just put the switch in programming mode, connect the device to a USB port on the PC. Launch ROMSet's creator and update.
• If you put the Multiply switch in programming mode, the Multyply is deactivated. It could also be considered as a Multiply ON-OFF. That is, in OFF the Multiply does not work, but the ROMSet's of the Dandanator do.
• Joystick ON-OFF
• Dual ROMSet. You can select one ROMSet or another, simply by changing a position switch. If you change the ROMSet switch position and it does not take the change, just press the right button of the ZX Dandanator MTD (or do a reset) and the other ROMSet is already selected.
• The two ROMSet's can be updated, either from the integrated Multiply, or from a DivIDE, DIVMMC, etc.
• "Pause" switch for games.
• Power LED.

In short, the ZX Dandanator MTD is a Dandanator 2.1b with Double ROMSet, Multiply integrated and some updates.

A few thoughts about my "Pause" switch:

• The Dandanator already includes a programmed pause. If during a game, the left button is pressed briefly, the game is stopped and will be resumed by pressing any key.
• When loading TAP or Z80 games from the Multiply, the "scheduled pause" leaves some screen corruption in the lower right corner. That screen corruption does not occur if we use the slide switch.
• The pause switch is designed for + 2A, + 2B and +3, although it will probably also work on 128K; but in the 48K it will not work as it should.
• The two pause methods do not interfere.

http://www.dandare.es

https://github.com/mad3001/Multiply