Retrocomputing BASIC Badge

2018 Hackaday Belgrade Hardware Badge

• Hardware Lead: Voja Antonic
• Software Lead: Jaromir Sukuba

Hardware details available on the BASIC Badge project page.

BASIC Word List:

Firmware at the day of conference was 1.00. There are new versions coming since then, see changes at https://github.com/Hack-a-Day/basic-badge/blob/master/firmware/badge1.X/changes.txt

Standard Words:

• print
• println
• if
• else
• goto
• gosub
• return
• for
• next
• end
• let
• rem

Badge Custom Words

• led X,Y - control LED, X[0..2] RGB, Y[0..1] on/off
• tune A,B,C,D - plays tones A, B, C for duration D
• clrscr - clear screen
• setxy X,Y - set cursor at X,Y
• wait X - wait for X ms
• color X,Y - X=Foreground, Y=Background using EGA 16-color palette
• chr X - prints character with ASCII representation X
• termt X - sets VT100 terminal on or off (1-on, 0-off)
• rnd X - function to return random number 0..X
• ein X - function to return value of expansion pin X
• eout X,Y - control expansion pin, X[0..3], Y[0..1] on/off
• edr X,Y - sets expansion pin function X[0..3], Y[0..1] output/input
• uin X - function to return received byte from serial port, if X=0, function is non-blocking, if X=1, function is blocking
• uout X - outputs value X to serial port as single byte
• input "string" - prints string and returns user entered value
• peek X - returns value from memory location X
• poke X,Y - write value Y into memory, on location X
• cursor X - turns cursor on (X=1) or off (X=0)
• kin X - function to return byte from keyboard, if X=0, function is non-blocking, if X=1, function is blocking

BASIC CLI commands

• run - runs program
• save X - Save program buffer to flash. There are 16 slots: X[0..15]
• load X - Load program into buffer from flash. There are 16 slots: X[0..15]
• list - list whole program
• more - list program by pages
• clr - clears all code from the program buffer
• free - prints amount of free program buffer
• sload - load new program into buffer from serial port
• ssave - output program buffer via serial port
• help - prints out basic BASIC help

Setting Up the Toolchain for BASIC Badge

The BASIC badge is based around a PIC32MX370F512H. Software is compiled using MPLABX, XC32 compiler, and legacy peripheral libraries from Microchip.

1. Download three packages:

   • Navigate to the Downloads" tab at the bottom of the Microchip Compilers page.
   • Download MPLAB® XC32/32++ Compiler v2.05 for your operating system
   • Download PIC32 Legacy Peripheral Libraries for your operating system
   • Navigate to the "Downloads" tab part way down the screen at the Microchip MPLAB X IDE page.

2. Install the packages:

   • Install the XC32 compiler first
   • Install the peripheral libraries next. IMPORTANT: You must specify the same directory as the XC32 compiler. This will likely not be the default option during install. For Linux installation this director was: /opt/microchip/xc32/v2.05/
   • Install MPLABX IDE

3. Open the MPLABX project from this repository

   • A PIC programmer like the PICKIT3 is required to program your badge
   • On the PIC programmer, pins 1-5 correspond to RES, V+, GND, B0, and B1 on the badge

Using XMODEM

Badge side

• Launch "CP/M @ Z80" on the badge
• b:
• xmdm r e:ZORK1.DAT

Linux XMODEM info

• sudo apt-get install lrzsz
• sudo chmod 777 /dev/ttyUSB0
• sx -X ZORK1.DAT > /dev/ttyUSB0 < /dev/ttyUSB0

Proposed Functionality

• High Importance:
  • BASIC interpreter
  • Line editor for BASIC programs
  • Save/Load ability (stored in program memory)
  • Simple menu system
• Medium Importance
  • Hardware control on expansion port
  • Game(s) that come with the badge
  • Ability for users to write C files and compile them into new firmward to flash to badge
• Low Importance
  • Serial connection allows users to program BASIC onto badge from computer without full reflash (needs USB to serial adapter)
  • Programming challenge? Like a game that encourages writing BASIC to solve it
  • Bling (demos that run on the badge)