The 85B Personal Computer combines an alphanumeric keyboard, CRT screen, thermal printer, tape drive, user read/write memory, and a ROM based operating system in one portable package. There are 64 kbytes of memory built into the 85B. Of this, 32 kbytes are directly addressable as user-available read/write memory. The other 32 kbytes (expandable to 544 k), called Electronic Disc memory, are indirectly addressable via built-in mass storage commands. Typewriter style keyboard includes eight user-definable keys which make it easier to write, execute, and control your programs. Use the built-in printer to produce hard copy of your results, print your programs, etc. And, you can take along both data and software on tape cartridges that run on the built-in tape drive. Four I/O ports on the back allow easy interfacing to peripherals and instruments.