Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!lll-lcc!pyramid!leadsv!ereed
From: ereed@leadsv.UUCP (Ed Reed)
Newsgroups: comp.sys.mac
Subject: FSRead problem on MacII
Keywords: FSRead
Message-ID: <4793@leadsv.UUCP>
Date: 21 Nov 88 19:26:58 GMT
Distribution: na
Organization: LMSC-LEADS, Sunnyvale, Ca.
Lines: 23



I am having a problem with the FSRead command on a Macintosh II. The
problem is as follows:

I have three processors, the Mac II, a Force single board computer, and a high
speed processor board.  The Force is the traffic cop of the system. When the
system is running the HSP sends data to a register which the Force reads. The
Force then takes that data and sends it to the Mac II. The problem is in order
to maintain a realtime system, the Force sends a byte of data to the Mac II 
every iteration of the control loop. Now FSRead appears to be only getting part
of the data. In a test case 0 to 255 was sent from the Force to the Mac II, and
approximately every 3rd byte was read. The other bytes where zeroed. Any
suggestions. The actual Mac code is:

FSRead (InPort, 256, &DataIn);

and was written in C using Lightspeed C ver 3.0.

Please reply to Joe Hughes

Joe Hughes
pyramid!leadsv!jhughes