Library routines move onward

The support library is coming along quite well, I'm quite pleased with it. It currently occupies only four pages of ROM memory, and wastes only about 6 bytes - this is because a TMS1100 divides memory into pages of 64 bytes and you can't cross to a different page without a jump, it's not like a Z80 where memory is contiguous.

The screenshot uses about 12 bytes to - clear the screen, play a beep, display a number and increment it (the latter is for keeping scores and so on) - you can actually see most of the code in the screen shot. It operates like a fast counter. I suspect on a real Microvision it would be extremely blurry in the least significant digit because the LCD isn't one of the greatest available.

Functionality at present is :

• Microvision hardware initialisation
• Writing a row or column bit pattern to the LCD latches given a row or column number
• Performing a Display Update
• Performing Display Polarisation switching
• A sound system that runs in the background (sort of - it toggles the speaker on the update and does the timing on the polarisation) which allows beeps of about 0.5 seconds or so and half a dozen different beeps, all dependent on how frequently you update the screen :)
• 3 x 5 digit font for scores / settings and the code to select it.
• Render a four digit number to the screen at any vertical position, optionally updating font data
• Clear screen routine / Zero score routine
• 4 bit Random Number Generator - bit rubbish but useable.
• Add 1, 10 or 100 to the 4 digit number (for scoring, mostly)

There's no keyboard routines or other utility functions - not sure what to provide, rotate functions maybe ?