Tapuino / Tape Emulation Mods

**Tapuino / Tape-Port Emulation Mods**
Caption	Tapuino OLED v1.5 assembled on a single 5 × 7 cm PCB
Type	External solid-state replacement for Commodore Datasette
Designer	Andrew Beer (“Sweetlilmre”) – original Tapuino design; Community forks: Arananet Reloaded, OpenC64 Tapuino, Tapuino OLED, Tapuino W, etc.
Manufacturer	Unknown
First released	April 2014 – public GitHub release of Tapuino v1.0 firmware
Latest revision	Tapuino firmware v2.01 (Feb 2023)
Operating voltage	5 V DC (drawn from cassette port pin 2)
Layers / PCB	—
Compatibility	Commodore 64, 64C, SX-64, VIC-20, C16/+4, PET* (with adaptor) – any IEC-less CBM 8-bit that uses the 1530/1531 Datasette interface
Features	—
Model No.	—

The Tapuino is an open-hardware, Arduino-based device that emulates Commodore’s 1530 Datasette mechanism, allowing cassette images (‎*.TAP*, ‎*.PRG*, ‎*.TCRT*) stored on a micro-SD card to be loaded, saved, and fast-forwarded with perfect digital fidelity. Because it plugs into the cassette port rather than the serial IEC bus, Tapuino is an attractive solution for VIC-20 owners and for C64 software that was never released on disk.

History

2014-04 – Tapuino v1.0 published on GitHub; Arduino Pro Mini + 16×2 LCD shield, push-buttons and SD-module.
2015-02 – Hackaday write-up brings wider attention; hundreds of DIY units are built.
2016-17 – “Reloaded” & OLED forks replace the LCD with a 128×32 I²C OLED and move to an Arduino Nano for native USB flashing.
2019 – Tapuino-W adds ESP-8266 Wi-Fi so images can be pushed over the network.
2022 – Tapuino v2.x firmware rewrites the loader to support Turbo-TAPE fast-loaders and arbitrary sample rates up to 100 kHz.

Hardware Overview

Variant	MCU / Clock	Display	Media	Notable Features
Tapuino v1.0	Atmega328P @ 16 MHz	16×2 HD44780 LCD	micro-SD	Through-hole shield stack
Tapuino OLED	Atmega328P	128×32 OLED	micro-SD	Smaller 5 × 7 cm PCB, rotary encoder option
Tapuino Reloaded	Atmega328P (Nano)	128×32 OLED	micro-SD	All-SMD, USB update, protected 5 V regulator
Tapuino-W	ESP-8266 (NodeMCU)	128×64 OLED	micro-SD / Wi-Fi	HTTP file upload, OTA firmware
OpenC64 Datasette Saver	STM32F103	0.96" IPS	micro-SD	Adds over-current & brown-out protection

Electrical Interface

The Tapuino connects to the six-pin cassette port:

+5 V (pin 2) – powers the MCU (≈70 mA peak with OLED).
GND (pin 1)
MOTOR output (pin 5) – emulated by polling; Tapuino ignores the line or gates file play.
READ (pin 4) – 0/+5 V pulse stream generated by DAC/bit-bang at original 300 baud or turbo rates.
WRITE (pin 3) – edge-captured and stored as WAV-like data when user presses “Record”.
SENSE (pin 6) – always pulled low (tape present).

Opto-isolation is optional; most PCBs use 74HC14/LM311 to shape the READ line back to digital logic levels.

Firmware & File Support

Current stock firmware (v2.xx) recognises:

.TAP v0/v1 images up to 64 MB.
.PRG files auto-wrapped in a minimal TAP header.
.TCRT (Tapecart) container – load *instantaneously* via turbo @ 38 kBaud.
Partial experimental support for TurboTape, SpeedDOS, Vorpal timing.

Menu navigation is via four push-buttons (Next, Prev, Play, Stop) or a rotary encoder; long-press on STOP enters settings where motor-sense polarity, turbo-boost and LCD contrast can be tweaked.

Building Your Own

A DIY Tapuino can be completed for US$15–20 in parts:

Mandatory: * Arduino Nano (ATmega328P); * micro-SD module (5 V tolerant); * 0.96″ monochrome OLED (I²C); * 74HC14 Schmitt trigger + 2N3904 for READ shaping; * 6-pin edge connector or sacrificial Datasette cable

Optional: * Level-shifting buffer for WRITE; * Protective polyfuse on +5 V line; * 3D-printed enclosure

Gerbers for multiple boards (Reloaded, Mini, Slim) are on GitHub under CERN-OHL-S or GPL-2.0 licences.

Usage Tips

Hold Play at power-on to enter fast-loader patch mode – needed for some turbo loaders that poll the keyboard.
Keep SD cards formatted as FAT32 with 8.3 filenames; deep directory trees slow the directory parser.
You can record real tapes: insert blank SD, press ➤⏺ combo and start the physical tape in the Datasette.
For VIC-20, set *AUTO-PRG offset* to $1201 so PRG files auto-run after load.

Alternatives & Related Projects

Tapecart Micro-SD – cartridge-sized STM32 design streaming PRGs at 38 kBaud.
Casduino / ArduiTape – WAV player on Arduino Nano feeding READ line with pure analogue audio.
Super‐SCP TapeCart Deluxe – CPLD-based loader with 2 MB internal flash.
Pi1541 “Tape Mode” – Raspberry Pi emulates both IEC disk and cassette via GPIO add-on.

Limitations

Will not power a real Datasette motor; cannot be daisy-chained.
SAVE speed is limited to original 300 baud even in v2 firmware.
Very long turbo loaders (>100 kB/s) may exceed the 16 MHz timer resolution.
C16/+4 require a €3 1531-to-1530 passive adaptor due to different pin-out.