using system serial drivers

[David]

I have not measured the performance of doing bulk vs one char transfers.
Have any of you bothered to read the code in the driver you are calling
and see what overhead is imposed on entry/exit? It is quite abit.
Some synths already have their own catch up handlers, so it would be quite
easy to write a new do_catchup that used the new serial
i/o and each synth could call the new one when appropriate.
With respect to isa cards, I wrote the dec pc driver for the
old long isa card so I am aware of the fact that
all drivers do not use serial ports.

[Samuel Thibault]

Hello,

Post by David
Have any of you bothered to read the code in the driver you are calling
and see what overhead is imposed on entry/exit? It is quite abit.

That's still extremely slow compared to the actual time spent by
hardware to send the bytes over the wire. Really, nowadays we have
billions of instructions per seconds with all kinds of hardware
predictions to make things fast. The whole kernel has moved to making
things object-oriented to make it more modular etc., speakup can really
afford the same.

Post by David
Some synths already have their own catch up handlers, so it would be quite
easy to write a new do_catchup that used the new serial
i/o and each synth could call the new one when appropriate.

That'd bring more complexity that needed.

Really, what is costly nowadays is human time to write & read code, not
hardware time.

Samuel

[Samuel Thibault]

Post by Samuel Thibault

Post by David
Have any of you bothered to read the code in the driver you are calling
and see what overhead is imposed on entry/exit? It is quite abit.

That's still extremely slow compared to the actual time spent by
hardware to send the bytes over the wire.

Oops, sorry, I meant "low" instead of "slow".

Samuel