Kurts Blog of Photography, minicomputers, mainframes, lightwave communications, and just whatever.

This post is a little different. It shows a typical login session on the PMC-20. You start by connecting via a ssh session: Workstation1:~ $ ssh kurt@pmc20 kurt@pmc20's password: Last login: Fri Jan 26 16:24:37 2018 from pi1   #     # ######  #######     #######  #####   #####   ##   ## #     # #           #     # #     # #     #   # # # # #     # #           #     # #             #   #  #  # ######  #####       #     #  #####   #####   #     # #       #           #     #       #       #   #     # #       #           #     # #     # #     #   #     # #       #######     #######  #####   #####       --- Welcome to MPE on the PMC-20 --- To view available commands type 'commands' at the prompt. For command help, type 'help [command]', or just 'help'. You will be logged out after 20 minutes of inactivity. Assigned JOB number 114 ~/kurt> commands *** MPE Built-in Commands *** cd               change directories help             show this help file exit 

A few notes on my mini computer. I re-wrote MPE (the user shell/commands/accounting system) on and off over the last few months. MPE is now version 3.02. I’ve added a lot of user programs and added features to the utilities I already completed. I’m finishing up a line editor that’s somewhere between ED for the pdp-8 and TECO. All the user utils  (cd, copy, attach, type etc) are multi-user safe and as optimized as I can make them. I found out about the Linux kernel  atime bug that breaks some of my system monitor stuff. Too bad the kernel devs want to keep it broken. Oh, well. I made a file system change that made a 200% speed up to the user experience. Very happy with that. I wrote a couple drivers for low speed and high speed paper tape readers. I wrote a tape drive driver. I can’t find my 500 mb tape drive so I emulated one using sequential files on various media. Really happy with it - I can type “tape save” and save versions of software in seconds. Lots faster than reel