DOS/51 · 80C31 Browser Emulator

SERIAL / 57600 BAUD 8N1starting…

Click the terminal and type. Try help, ls -l or asm -r primes.asm.

Machine

CPU80C31 · 11.0592 MHzROM32 KiB DOS/51 firmwareRAM2 × 32 KiBConsoleVT100 · 80 × 24

Both RAM chips are kept in this browser, so files survive a reload; Power cycle clears them. Nothing you type is uploaded.

SD card

The board has an SD card on P1.4–P1.7 (SPI). Here it is a 16 MiB FAT16 image stored in your browser. Card files use 8.3 names in the root directory.

Your first card includes dropblk.asm. Existing cards are unchanged until you click Add DropBlocks (FAT16). Download source for other cards or a real board. Insert card… accepts FAT16/FAT32 images up to 256 MiB.

Quick start

`help`	list commands
`ls -l`, `cat hello.asm`	bundled examples
`sdget dropblk.asm` `asm -r dropblk.asm`	play DropBlocks (arrows or WASD, Space drop, P pause, Q quit)
`asm -r primes.asm`	assemble to 8000h and run
`nano hello.asm`	editor (^O save, ^X exit)
`df`, `free`, `mem 8000 40`	disk, memory, hex dump
`sdput`, `sdls`, `sdget`, `sdrm`	SD card files

Files live in the 24 KiB RAM disk (XDATA 2000h–7FFFh). Programs, assembler output and the editor buffer use the upper 32 KiB, mapped into both XDATA and CODE.