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Expansion pack B for the eLeMeNt ZX

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  1. Description and installation
  2. Setup and control
  3. Additional mods
  4. Questions and Answers
  5. Contact (and orders)

This hardware is a second expansion available for the older eLeMeNt ZX motherboard v1. The first expansion was the Expansion pack A (AA-RAM), which upgrades the memory of the eLeMeNt to 4 MB.

The Expansion Pack B brings two new features to your eLeMeNt ZX computer:

  1. ESP/Wi-Fi module
  2. third USB port for another PC mouse or keyboard

These add-ons were of the greatest interest by users of the eLeMeNt ZX v1 and will be appreciated especially by those who do not have the MB03+ interface connected or do not use the motherboard as a replacement with the original +2A/+2 case, put the eLeMeNt ZX into a new Tiny case and lacked an internally connected mouse.

Note: In the eLeMeNt ZX v2 is this expansion already included, with connectors built directly onto the motherboard. The Expansion Pack B is intended for the motherboard v1 only.

The ESP/Wi-Fi module is connected and supported in the eLeMeNt ZX in such a way that it can work with software written for various ZX Spectrum and ZX-Uno Wi-Fi interfaces.


Description and installation

The Expansion Pack B consists of four parts: an expansion board, a small ESP/Wi-Fi module and two pin header connectors. The expansion board holds a second USB connector and a socket for the ESP/Wi-Fi module.

The expansion board is situated in the lower right corner of the eLeMeNt ZX motherboard. The position of the new USB connector is identical to a future version of the eLeMeNt's motherboard (where the second USB and a socket for the ESP/Wi-Fi module will be already included).

Current eLeMeNt ZX firmware can handle external PC mice and keyboards with PS/2 protocol. This means you have to use modern USB device which support the PS/2 standard or use a PS/2 to USB adapter for devices with older PS/2 plug.

Before placing the ESP/Wi-Fi module on the expansion board, make sure that small yellow DIP switches, located i the center of the module, are in the OFF position. On the picture below, you can see DIPs in the Dial switch, which has the OFF position towards the right.

The outline of the ESP/Wi-Fi module printed on the expansion board shows the direction in which to place the module. The blue plate on the module is directed towards the edge of the eLeMeNt ZX motherboard.

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The installation is not just click-able! First of all, you need to prepare a place for connecting the expansion board to the motherboard. The Expansion pack B requires soldering two pin header connectors to the eLeMeNt ZX motherboard.

The resulting placement of the expansion board on the header connectors looks like this:

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Setup and Software

The expansion board, the new USB port and the ESP/Wi-Fi module are already supported in the latest eLeMeNt´s FPGA core and also in the SetUp. If you have versions older than march of 2023, download the latest ones and follow the update instructions in the eLeMeNt ZX User Manual.

In the SetUp, USB connectors are basically set so that a mouse can be connected to the new USB of the epansion board and a PC keyboard to the old USB (in the back of the computer).

You can choose from three serial/UART types for the ESP/Wi-Fi module, from the fastest MB03+ type, through the ZXUNO´s in the middle, to the slowest (legacy) AY/128-serial.

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You can switch the Wi-Fi using OUTs from Spectrum's BASIC as well.
Type: OUT 30779, 57 : OUT 31035, [1,2 or 3] for one Wi-Fi interface of MB03+, ZXUNO or AY/128.

No other settings are needed, you can use various software, incl. a rich set of programs for older and slower Wi-Fi interfaces. Here is a basic software pack prepared for DOWNLOAD.

A firmware update of the ESP/Wi-Fi module firmware can be done using an AT command or using a cable. The ESP/Wi-Fi module is a "devkit" unbrickable version, which has its own usb connector for safe upgrade of firmware.

Additional mods

It is necessary to print a new bottom part of the Tiny case with a hole for the second USB connector. Model data for 3D printing are for download on the 128land website.

In case you get stuck during experimenting with the ESP/Wi-Fi module (eg. with AT commands), you normally need to turn off/on your computer to restart the module. In case you want to restart the ESP/Wi-Fi module just by pressing the reset button, you will have to solder one wire to your eLeMeNt ZX motherboard, see the enclosed picture.

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Questions and answers

What is the price of the Expansion Pack B?
The total price is 30 eur + postage, for the whole set (expansion board+module).

I already have an ESP/Wi-Fi module, can I purchase the expansion board only, without the module?
Yes, the board (without the module) is for 20 eur + postage.

Can I buy an ESP/Wi-Fi module itself from you, without an expansion board?

What modern USB mouse or USB keyboard support the PS/2 protokol?
You will find them in the List of eLeMeNt ZX compatible peripherals.

The Expansion Pack B seems to be tall. Will it fit into my ZX Spectrum case?
It fits easily in the case for which the eLeMeNt ZX is intended, either in the modern Tiny case (v2.0) or in the ZX Spectrum +2 and +2A cases.

Where could I find a list of AT commands for the ESP/Wi-Fi module?
Look for the document "ESP8266 AT Instruction Set", www.128land.com or www.espressif.com.

Where could I read about technical parameters of the ESP/Wi-Fi module?
Look at the ESP8266 datasheet.

Where is a programmer's reference for making Wi-Fi apps on the eLeMeNt ZX?
Go to www.128land.com

I do not need the expansion board, can I connect the ESP/Wi-Fi module directly to the motherboard?
Yes, five wires are needed, between the module and the eLeMeNt ZX motherboard, see the scheme above.

Instead of the ESP/Wi-Fi module, does an UART/RS-232 converter work with the eLeMeNt ZX?
Yes, use a device such as the MAX232, four wires are needed for the connection. In the SetUp, switch to "UART ZX128-AY / PS2 disabled".

Can I use several UART/serial/Wi-Fi connections at the same time?
Can I use serial transmissions via cable simultaneously with a Wi-Fi interface turned on?
No, currently the eLeMeNt ZX core/firmware provides only one UART device and allows you to link it with one of four serial and Wi-Fi interfaces available in the eLeMeNt/MB hardware.

contact and user support:
Telegram / SpectrumComputing forum (EN) / Oldcomp forum (CZ)

more about the eLeMeNt/MB platform: http://128land.com/

software: http://zxfiles.net/