Many years ago I wrote assembler for a 6800-based mini with very simple display screens - 8 rows of 32 characters, each character being encoded by 6 bits for the value (no lower case), along with one bit for "underline" and one bit for "flashing".
The displays were directly memory mapped in 256-byte blocks starting at 0xc000, and the O/S also split memory up into 256-byte buffers. So if you wanted to see what was actually going on, you just poked 0xc1 into a buffer-id to get a real-time display on VDU 1 of what the program on VDU 0 was doing.
Tell people these days that you used to work with a multi-tasking O/S on an 8-bit platform capable of driving 48 VDUs and 56 printers with 48K of RAM and they laugh at you. :(
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.
| & || & |
| < || < |
| > || > |
| [ || [ |
| ] || ] ||