/ESPectrum

A ZX spectrum 48K, 128K and Pentagon 128 emulator running on the Espressif ESP32 SoC

Primary LanguageCGNU General Public License v3.0GPL-3.0

ESPectrum

This is an emulator of the Sinclair ZX Spectrum computer running on Espressif ESP32 SoC powered boards.

Currently, it can be used with Lilygo's TTGo VGA32 board, Antonio Villena's ESPectrum board and ESP32-SBC-FabGL board from Olimex.

Just connect a VGA monitor or CRT TV (with special VGA-RGB cable needed), a PS/2 keyboard, prepare a SD Card as needed and power via microUSB.

This project is based on David Crespo excellent work on ZX-ESPectrum-Wiimote which is a fork of the ZX-ESPectrum project by Rampa and Queru which was inspired by Pete's Todd PaseVGA project.

Features

  • ZX Spectrum 48K, 128K and Pentagon 128K 100% cycle accurate emulation (no PSRAM needed).
  • Perfect Z80 emulation (Authored by José Luis Sánchez)
  • Selectable Sinclair 48K, Sinclair 128K and Amstrad +2 english and spanish ROMs.
  • Possibility of using one 48K and one 128K custom ROM with easy flashing procedure from SD card.
  • ZX81+ IF2 ROM by courtesy Paul Farrow with .P file loading from SD card.
  • 6 bpp VGA output in three modes: Standard VGA (60 and 70hz), VGA 50hz and CRT 15khz 50hz.
  • Support for two aspect ratios: 16:9 or 4:3 monitors (using 360x200 or 320x240 modes)
  • Multicolor attribute effects emulated (Bifrost*2, Nirvana and Nirvana+ engines).
  • Border effects emulated (Aquaplane, The Sentinel, Overscan demo).
  • Floating bus effect emulated (Arkanoid, Sidewize).
  • Contended memory and contended I/O emulation.
  • AY-3-8912 sound emulation.
  • Beeper & Mic emulation (Cobra’s Arc).
  • Dual PS/2 keyboard support: you can connect two devices using PS/2 protocol at the same time.
  • PS/2 Joystick emulation (Cursor, Sinclair, Kempston and Fuller).
  • Two real joysticks support (Up to 8 button joysticks) using ESPjoy adapter or DIY DB9 to PS/2 converter.
  • Emulation of Betadisk interface with four drives and TRD (read and write) and SCL (read only) support.
  • Realtime (with OSD) and fast TAP file loading.
  • TAP file saving to SD card.
  • SNA and Z80 snapshot loading.
  • Snapshot saving and loading.
  • Complete file navigation system with autoindexing, folder support and search functions.
  • Complete OSD menu in two languages: English & Spanish.
  • BMP screen capture to SD Card (thanks David Crespo 😉).

Work in progress

  • +2A/+3 models.
  • TZX support.
  • DSK support.
  • On screen keyboard.

Installing

You can flash the binaries directly to the board if do not want to mess with code and compilers. Check the releases section

Compiling and installing

Quick start from PlatformIO:

  • Clone this repo and Open from VSCode/PlatFormIO
  • Execute task: Upload
  • Enjoy

Windows, GNU/Linux and MacOS/X. This version has been developed using PlatformIO.

Install platformIO:

  • There is an extension for Atom and VSCode, please check this website.
  • Select your board, pico32 which behaves just like the TTGo VGA32.

Compile and flash it

PlatformIO > Project Tasks > Build , then

PlatformIO > Project Tasks > Upload.

Run these tasks (Upload also does a Build) whenever you make any change in the code.

Prepare micro SD Card

The SD card should be formatted in FAT16 / FAT32.

Just that: then put your .sna, .z80, .p, .tap, .trd and .scl whenever you like and create and use folders as you need.

There's also no need to sort files using external utilities: the emulator creates and updates indexes to sort files in folders by itself.

PS/2 Keyboard functions

  • F1 Main menu
  • F2 Load (SNA,Z80,P)
  • F3 Load custom snapshot
  • F4 Save customn snapshot
  • F5 Select TAP file
  • F6 Play/Stop tape
  • F7 Tape Browser
  • F8 CPU / Tape load stats ( [CPU] microsecs per CPU cycle, [IDL] idle microsecs, [FPS] Frames per second, [FND] FPS w/no delay applied )
  • F9 Volume down
  • F10 Volume up
  • F11 Hard reset
  • F12 Reset ESP32
  • CTRL + F1 Hardware info
  • CTRL + F2 Turbo mode
  • CTRL + F5..F8 Screen centering in CRT 15K/50hz mode
  • CTRL + F9 Input poke
  • CTRL + F10 NMI
  • Pause Pause
  • PrntScr BMP screen capture (Folder /.c at SDCard)

ZX Keyboard functions

Press CAPS SHIFT + SYMBOL SHIFT and:

  • 1 Main menu
  • 2 Load (SNA,Z80,P)
  • 3 Load custom snapshot
  • 4 Save custom snapshot
  • 5 Select TAP file
  • 6 Play/Stop tape
  • 7 Tape browser
  • 8 CPU / Tape load stats ( [CPU] microsecs per CPU cycle, [IDL] idle microsecs, [FPS] Frames per second, [FND] FPS w/no delay applied )
  • 9 Volume down
  • 0 Volume up
  • Q Hard reset
  • W Reset ESP32
  • I Hardware info
  • T Turbo mode
  • Z,X,C,V Screen centering in CRT 15K/50hz mode
  • O Input poke
  • N NMI
  • P Pause
  • S BMP screen capture (Folder /.c at SDCard)

How to flash custom ROMs

Two custom ROMs can be installed: one for the 48K architecture and another for the 128K architecture.

The "Update firmware" option is now changed to the "Update" menu with three options: firmware, custom ROM 48K, and custom ROM 128K.

Just like updating the firmware requires a file named "firmware.bin" in the root directory of the SD card, for the emulator to install the custom ROMs, the files must be placed in the mentioned root directory and named as "48custom.rom" and "128custom.rom" respectively.

For the 48K architecture, the ROM file size must be 16384 bytes.

For the 128K architecture, it can be either 16kb or 32kb. If it's 16kb, the second bank of the custom ROM will be flashed with the second bank of the standard Sinclair 128K ROM.

It is important to note that for custom ROMs, fast loading of taps can be used, but the loading should be started manually, considering the possibility that the "traps" of the ROM loading routine might not work depending on the flashed ROM. For example, with Rodolfo Guerra's ROMs, both loading and recording traps using the SAVE command work perfectly.

Finally, keep in mind that when updating the firmware, you will need to re-flash the custom ROMs afterward, so I recommend leaving the files "48custom.rom" and "128custom.rom" on the card for the custom ROMs you wish to use.

Hardware configuration and pinout

Pin assignment in hardpins.h is set to match the boards we've tested emulator in, use it as-is, or change it to your own preference.

Project links

Supported hardware

Thanks to

Thanks also to all this writters, hobbist and documenters

And all the involved people from the golden age