From: sleeper75se (sleeper75se_at_yahoo.se)
Date: 2002-03-03 20:50:00
--- In buildcheapeeg_at_yahoogroups.com, "Jim Meissner" <jpmeissner_at_mindspring.com> wrote:
> If you have a remote A/D converter and microprocessor
> (such as you are planning to do) and sending serial
> data to the RS232 port, then it is much easier just to
> stream the data to the hard drive as it comes in. This
> should be an interrupt driven routine. THAT IS NUMBER
> ONE PRIORITY.
Hello Jim,
fortunately the read/write-loop does not have to be as tight as you
had to make it, so there is plenty of time to cook the data into a
machine-independent form before dumping it to the harddrive. The
interrupt routine you are requesting is already implemented by the
OS. All you have tell it is what bitrate you want and how many
kilobytes of data it should buffer.
The real problem is increasing the priority of this interrupt, to
prevent data loss. In a standard Windows/Linux system, it has lowest
priority so you risk losing data (at 115kbps) as soon as you start
typing on the keyboard! There is a very simple way to fix this,
either by editing a registry key for Windows or running IRQtune for
Linux. However, I've not tested it myself, for this application, yet.
Regards,
Andreas
This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:39 BST