About

Michael Zucchi

 B.E. (Comp. Sys. Eng.)

  also known as zed
  & handle of notzed

Tags

android (44)
beagle (63)
biographical (88)
blogz (7)
business (1)
code (63)
cooking (30)
dez (7)
dusk (30)
ffts (3)
forth (3)
free software (4)
games (32)
gloat (2)
globalisation (1)
gnu (4)
graphics (16)
gsoc (4)
hacking (434)
haiku (2)
horticulture (10)
house (23)
hsa (6)
humour (7)
imagez (28)
java (224)
java ee (3)
javafx (48)
jjmpeg (77)
junk (3)
kobo (15)
libeze (7)
linux (5)
mediaz (27)
ml (15)
nativez (8)
opencl (119)
os (17)
parallella (97)
pdfz (8)
philosophy (26)
picfx (2)
playerz (2)
politics (7)
ps3 (12)
puppybits (17)
rants (137)
readerz (8)
rez (1)
socles (36)
termz (3)
videoz (6)
wanki (3)
workshop (3)
zcl (1)
zedzone (21)
Monday, 01 June 2009, 00:11

Press Any Key

Well that was a strange weekend. I felt very odd Saturday - very sore throat, dizzy, really nasty headache and a bit of a fever for a while. The fever and dizziness went but I've still got a damn sore throat (a bit less so). I slept a lot.

I managed to get sucked in to poking on code again ... and once I start it's hard to stop.

I wrote up a basic keyboard device - it's a user-mode server which listens to an incoming message port for requests messages and for interrupts. If it gets an interrupt it buffers the keys (and provides decoding/etc), and if it gets a request it returns a key from the buffer (or queues it until one comes along). Very simple code. Then I wanted to have it synthesize key repeats too -- I find the pc keyboard repeats too slowly -- so that meant looking at writing a timing sub system. I tried to think of how these devices should be setup and initialised but for now I've just hardcoded their process creation from the kickstart routine, and use a simple manual process for accessing them via a public port name.

So then I had to work out how to use the APIC for timing - I'll leave the PIC timer for scheduling for now. And with that, I wrote a preliminary 'timer.device', although I haven't tried to see if it works yet. I ummed and ahhed over putting the timing service directly in the kernel, rather than in a user-service. But the kernel can only send signals to processes, and the timer device can send messages, so it seems like it's more useful, even if there is a somewhat more overhead involved. Sigh, I wish there was another APIC timer or two, it would be nice to have a good reliable period counter as well as one to be reprogrammed for varying intervals.

Tagged hacking, os.
Cells and ratty rodents | It works
Copyright (C) 2019 Michael Zucchi, All Rights Reserved. Powered by gcc & me!