BBC BASIC for ESP32 MOS

Port of BBC BASIC (BBCSDL) to esp32-mos, targeting the ESP32-S3 (Xtensa LX7) and ESP32-P4 (RISC-V RV32IMAFC).

The interpreter runs as a bare-metal MOS user program. All I/O (console, file system, VDU) is delegated to the MOS API, keeping the BASIC core portable.

Prerequisites

• ESP-IDF toolchain installed (provides xtensa-esp-elf-gcc and/or riscv32-esp-elf-gcc).
• The esp32-mos project cloned as a sibling directory (../esp32-mos).

Cloning

git clone --recurse-submodules <this-repo-url>

If you already cloned without --recurse-submodules:

git submodule update --init

Building

Activate the ESP-IDF toolchain first:

source ~/esp/esp-idf/export.sh

ESP32-S3 (default)

make

ESP32-P4

make CHIP=esp32p4

The output is bbcbasic.bin, a flat binary ready to be loaded by MOS.

Installing

Copy the binary into the esp32-mos data partition:

make install              # ESP32-S3
make install CHIP=esp32p4 # ESP32-P4

This places bbcbasic.bin in ../esp32-mos/data/<chip>/.

Other targets

Target	Description
make clean	Remove all build artifacts
make disasm	Generate bbcbasic.asm disassembly

Project structure

src/                  Platform-specific source files
include/              ESP32 MOS-specific headers
BBCSDL/               BBCSDL submodule (interpreter headers)
Makefile              Build system
mos_user.ld           Linker script

License

The BBC BASIC interpreter source is Copyright (c) R. T. Russell. See the BBCSDL repository for license details.