marc@vub.UUCP (Marc Nyssen) (09/09/87)
As an intensive user of trains an buses, the advent of MINIX, in combination with truly portable lap-top computers arose my interest and in August,I did some testing and development with some of these machines mainly the Zenith181. Here is a summary of these activities, hopefully others can benefit from it: - Copying 5.25 inch floppies to 3.5 ones is quite tricky! Be sure the utilities you use do real byte to byte copy; then yuo are ok, but beware: some (ms)(ps)dos utilities I do obscure transforms, resulting corrupted 3.5 disks. Finally a friend, owning a self-built flex system wrote a simple byte-to-byte copy program: problem solved. - The Z181 booted right away with the good floppies; - The floppy driver gave errors most of the time; problem solved by augmenting the wait-time for arm-movements changed it from T/4 to 3*T/4 and no more errors; - 3.5 inch floppies can contain 720kB, to reach these, the number of the number of blocks in floppy.c was modified from 720 to 1440; - A self-contained machine does not interest me, I needed simple commu- nication by tty-port to dump the results of 3 hours train-bus-work to our network, to download new code and applications to my laptop; I extended tty.c with some of the additions posted by "Bing Bang"; without however introducing "virtual screens" and leaving a max of the original code intact; now I can download in both directions but dont know the limitations: to go easy at first, I put the speed at 300bps. - On the Z181 the command "time run" in the /user/test directory gave: real 10:40.0 user 1:40.5 sys 2:48.0 - Remaining small problems concern the arrow-keys and DEL (!) which are not directly understood by MINIX as such ..., the real-time clock and calendar feature which are not exploited right now, perhaps with the recent posting for AT-cal. this would be OK. For a general cleanup of tty.c, I wait until I install the 1.2 version by the way, did not get all the defines, used in Bing-Bang's driver, had to reconstruct them from the Western Digital 8250 datasheet. - Yesterday, a short test could be made with the Z183, with 8Mhz clock and 10Mb disk; apparenly there is a problem with the HD; from test10, we got disk read errors; perhaps because I have MINIX1.1 xt_wini.c the 1.2 version might solve the problem; unfortunately I missed it on the net ... - My new kernel olso works on the T1100+ where the known scrolling problem was encountered, also on the 1200, but extensive testing could not be done on these machines, not to endanger the data on HD. Conclusion: If you want a laptop UNIX, only the price-tag of the machine may be an obstacle, these machines (with MINIX) can turn a long journay or even delayed trains into a more enjoyable experience, giving you on the same occasion the opportuni- ty to do real useful work like entering text, testing shell scripts, ... A pity "awk" is not on MINIX ... Thanks to Bdale, Bing-Bang and others for useful info (by news and mail), Congratulations to ast for the excellent book and interesting ideas. Greetings to all, Marc Nyssen Medical Informatics Dept. Vrye Universiteit Brussel BELGIUM