Comment by dtgriscom
12 days ago
I remember in the early '80s using a computer (a Xerox Star, perhaps?) that used the CPU to generate the display. To speed up CPU-intensive tasks, you could blank the screen.
12 days ago
I remember in the early '80s using a computer (a Xerox Star, perhaps?) that used the CPU to generate the display. To speed up CPU-intensive tasks, you could blank the screen.
Alto had its entire display control in microcode, IIRC.
Out of similar tricks, Symbolics 3600 (at least first model) had major portions of disk driver implemented as one of the tasks in microcode (yes, the microcode was a multi-tasking system with preemption). Don't know how much of MFM wrangling was going there, but ultimately it meant that reading and writing a page from/to disk was done by means of single high level instruction