- Oberon - mailman3.inf.ethz.ch

Re: [Oberon] Documentation for Gadgets; was Re: Software Tracking Project
by Treutwein Bernhard 23 Mar '22

23 Mar '22

afaik the Oberon Companion is out of print, but an online version should be available on every S3/ETH-Oberon. instructions how to create a printed personal copy should be/were present in the Oberon wikibook. Sent from Nine<http://www.9folders.com/> ________________________________ Von: Dieter <d.gloetzel(a)web.de> Gesendet: Mittwoch, 23. März 2022 09:17 An: oberon(a)lists.inf.ethz.ch Betreff: Re: [Oberon] Documentation for Gadgets; was Re: Software Tracking Project I also recommend "The Oberon Companion" by Andre Fischer and Hannes Marais ISBN 3-7281-2493-1 vdf Hochschulverlag AG ETH Zürich Regards, Am 23.03.2022 um 04:50 schrieb peter(a)easthope.ca: > >From skulski at pas.rochester.edu Mon Jan 29 06:27:36 2018 >> My experience with Gadgets was mixed, but I appreciate their >> potential. > I was baffled by Gadgets although didn't make a real study. > > >From joerg.straube at iaeth.ch Tue Mar 6 18:51:28 2018 >> Did you read this intro into the Gadget system: >> http://www.ethoberon.ethz.ch/ethoberon/tutorial/GadgetsIntro.html > André Fischer gave permission to incorporate his tutorials into > the wikibook. The Gadgets pages are there, cited in the Contents page. > https://en.wikibooks.org/wiki/Oberon/ETH_Oberon/Tutorial > > I've read all of the tutorials now. Focussed more on typographical > errors and format than on concepts but well convinced that Gadgets can > be tackled with help of the tutorials. > > Regards, ... P.L. > > -- ____________________________________ Dr. Dieter Glötzel Im Rosengarten 27 64367 Mühltal Tel.: 06151 / 360 82 72

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Documentation for Gadgets; was Re: Software Tracking Project
by peter＠easthope.ca 23 Mar '22

23 Mar '22

>From skulski at pas.rochester.edu Mon Jan 29 06:27:36 2018 > My experience with Gadgets was mixed, but I appreciate their > potential. I was baffled by Gadgets although didn't make a real study. >From joerg.straube at iaeth.ch Tue Mar 6 18:51:28 2018 > Did you read this intro into the Gadget system: > http://www.ethoberon.ethz.ch/ethoberon/tutorial/GadgetsIntro.html André Fischer gave permission to incorporate his tutorials into the wikibook. The Gadgets pages are there, cited in the Contents page. https://en.wikibooks.org/wiki/Oberon/ETH_Oberon/Tutorial I've read all of the tutorials now. Focussed more on typographical errors and format than on concepts but well convinced that Gadgets can be tackled with help of the tutorials. Regards, ... P.L. -- mobile: +1 778 951 5147 VoIP: +1 604 670 0140 48.7693 N 123.3053 W

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Documentation for Gadgets; was Re: Software Tracking Project
by peter＠easthope.ca 23 Mar '22

23 Mar '22

>From skulski at pas.rochester.edu Mon Jan 29 06:27:36 2018 > My experience with Gadgets was mixed, but I appreciate their > potential. I was baffled by Gadgets although didn't make a real study. >From joerg.straube at iaeth.ch Tue Mar 6 18:51:28 2018 > Did you read this intro into the Gadget system: > http://www.ethoberon.ethz.ch/ethoberon/tutorial/GadgetsIntro.html André Fischer gave permission to incorporate his tutorials into the wikibook. The texts are there now, cited in the Contents page. https://en.wikibooks.org/wiki/Oberon/ETH_Oberon/Tutorial I'm still working on the illustations. I've read all of the tutorials now. Focussed more on typographical errors and format than concepts. Well convinced of the value of the tutorials. Regards, ... P.L. -- mobile: +1 778 951 5147 VoIP: +1 604 670 0140 48.7693 N 123.3053 W

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A whiteboard application for explaining ideas
by Srinivas Nayak 22 Mar '22

22 Mar '22

Dear All, Here is a simple application I created. A Simple, Powerful, Free, Brainstorming Whiteboard https://github.com/snayaksnayak/iMage/releases/download/v1.0/iMage_v1.0.zip Kindly have a look at it. I Hope, you can use it while teaching. Sincerely, Srinivas Nayak

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Re: [Oberon] OBNC Sets incorrect output
by Joerg 21 Mar '22

21 Mar '22

Joe Most probably the compiler itself is not compiled with --c-int-type=long. The difference between the first and the second are the set constants. To check my assumption try: > MODULE testsets; > IMPORT Out; > VAR > i : INTEGER; > x,y,z : SET; > BEGIN > x := {}; INCL(x, 31); INCL(x, 32); INCL(x, 33); > y := {}; INCL(y, 33); INCL(y, 34); INCL(y, 35}; > z := x - y; > FOR i := 31 TO 35 DO > IF i IN z THEN > Out.Int(i,4) > END > END; > Out.Ln > END testsets. If this solved the output and you have access to the source, you could try to re-compile the compiler with the long flag turned on. br Jörg

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OBNC Sets incorrect output
by Joe Turner 20 Mar '22

20 Mar '22

If you build OBNC on a 64 bit system with --c-int-type=long you can use integers between 0-63 in sets. I confirmed this using the code provided on the FAQ page at the OBNC site (slightly modified because I removed the procedure): MODULE setSize; IMPORT Out; VAR x : INTEGER; s : SET; BEGIN x := -1; s :=-{}; REPEAT INC(x); EXCL(s,x) UNTIL s = {}; Out.Int(x,4); Out.Ln END setSize. The output is 63. However, the following code should produce the output : 31 32. MODULE testsets; IMPORT Out; VAR i : INTEGER; x,y,z : SET; BEGIN x := {31,32,33}; y := {33,34,35}; z := x - y; FOR i := 31 TO 35 DO IF i IN z THEN Out.Int(i,4) END END; Out.Ln END testsets. But it doesn't. The output is 31. Other set operations also produce output limited to a maximum set size of 31. -- Sent with https://mailfence.com Secure and private email

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Wiznet W5500 code for Oberon System?
by Skulski, Wojciech 16 Mar '22

16 Mar '22

All: I remember some remarks concerning the Wiznet W5500 support for Oberon System. We would like to start using this chip. We have the Arty A7-35 and the Arduino W5500 shield which works with Arty. We also have some C++ code driving the W5500 with MicroBlaze. We would like to start using both Astrobe and the Oberon System for this project. It would give us a boost if we could use the existing code rather than port from from C++. Eventually we would like to develop a serial-over-Ethernet using W5500, an embedded web server, and other such services. I wonder if any W5500 code is available anywhere, or should we give up searching and develop our own. FYI, W5500 is a silicon chip with embedded TCP/IP on chip. You send data buffers to it via SPI, and the chip is driving the Ethernet side with properly structured TCP/IP packets. So it is basically a SPI-to-Ethernet translator. It helps to avoid the burden of maintaining the TCP/IP stack within the Oberon System. Thank you, Wojtek

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Fun with π
by Hans Klaver 15 Mar '22

15 Mar '22

Hi all, Here are a few programs to have fun with π. The first is just a joke, and shows how even Oberon code can be obfuscated ;-) It calculates π by measuring the surface of a round disc. Feeding it larger discs increases the number of decimals of π, but only very gradually: you need a ten times larger disc to gain one decimal precision. The second one is more interesting because the algorithm used produces quite a lot of digits of pi using only ordinary integer operations; no need for floating point or some arbitrary-precision datatype. In Oberon System V5 it can calculate about 10,000 digits, and several hundreds of thousands of digits can be produced by a slight variation of the algorithm run from the command line (see the third program). -- Hans Klaver MODULE Westley; (* hk 3.14.2022 *) (* After an obfuscated C program by Brian Westley (IOCCC, 1988). Select (the start of) a circle and middle click Westley.FOO @ Note that the underscore is not rendered well in Oberon10 font, so use Courier10 font to draw circles. Separate two circles with "~~~". *) IMPORT Foo := In, FoO := Out; PROCEDURE FOO*; (* just foo'ing around *) CONST BAR = 9X; Bar = 0DX; baR = 20X; bar = 2DX; BaR = 5FX; VAR foo: CHAR; F,OO: REAL; f,O0: INTEGER; BEGIN f:=0;O0:=0; Foo.Open; Foo.Char(foo); WHILE Foo.Done & (foo # "~") DO WHILE (foo = BAR) OR (foo = Bar) OR (foo = baR) DO Foo.Char(foo) ELSIF foo = BaR DO DEC(f); DEC(O0); Foo.Char(foo) ELSIF foo = bar DO DEC(f); Foo.Char(foo); Foo.Char(foo) END; Foo.Char(foo); Foo.Char(foo) END; F := FLT(f); OO := FLT(O0); FoO.Real(4.0*(-F)/OO/OO, 12); FoO.Ln END FOO; END Westley.FOO @ Edit.ChangeFont Courier10.Fnt _-_-_-_ _-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_ _-_-_-_ ~~~ _-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ -_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ -_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_-_-_-_-_-_-_ _-_-_-_-_-_ ~~~ MODULE PiSpigot4; (* hk 3.14.2022 *) (* PiSpigot4.Compute *) (* Computes pi to (a few more than) N decimal digits. After an obfuscated C program by Dik T. Winter at CWI Amsterdam, (that computes 800 digits of pi) and its rewrite in C by Ben Lynn. int a=10000,b,c=2800,d,e,f[2801],g;main(){for(;b-c;)f[b++]=a/5; for(;d=0,g=c*2;c-=14,printf("%.4d",e+d/a),e=d%a)for(b=c;d+=f[b]*a, f[b]=d%--g,d/=g--,--b;d*=b);} It uses a 'spigot' algorithm (dripping out digits as if from a tap, in this special case four by four) and does not use the digits after they are computed. Based on evaluation of a mathematical series that is a mixed-radix representation of pi with variable base = ( 1/3, 2/5, 3/7, 4/9, ...); in this base pi is simply a list of 2's. Lit.: S. Rabinowitz & S. Wagon, A Spigot Algorithm for the Digits of π. The American Mathematical Monthly, Vol. 102, No. 3 (Mar., 1995), pp. 195-203 Jörg Arndt and Christoph Haenel. 'π Unleashed', 2nd ed., 2001. https://www.maa.org/sites/default/files/pdf/pubs/amm_supplements/Monthly_Re… https://crypto.stanford.edu/pbc/notes/pi/code.html *) IMPORT Out; CONST N = 10000; (* number of digits of pi to compute; max. 10015 on Oberon V5 *) len = (N DIV 4 + 1) * 14; VAR f: ARRAY len OF INTEGER; (* array of 4-digit decimals *) PROCEDURE Compute*; CONST a = 10000; (* new base, 4 decimal digits *) aDIV5 = a DIV 5; VAR b, (* numerator previous base *) c, (* counter *) d, (* accumulator & carry *) e, (* saves previous 4 digits *) g: INTEGER; (* denominator previous base *) PROCEDURE WritePaddedInt (x, n: INTEGER; ch: CHAR); (* Write integer x in a field of at least n characters, padded to the left with enough characters ch to fill the whole field *) VAR i, x0: INTEGER; BEGIN i := 0; x0 := x; REPEAT x0 := x0 DIV 10; INC(i) UNTIL x0 = 0; (* x has i digits *) WHILE n > i DO Out.Char(ch); DEC(n) END; Out.Int(x, 0) END WritePaddedInt; BEGIN ASSERT(N < 54933); (* at digit 54936 pi has 4 zero's at an index divisible by 4 which this version of the algorithm cannot handle properly *) FOR b := 0 TO len - 1 DO f[b] := aDIV5 END; (* initialize the array with 2000's *) e := 0; FOR c := len - 1 TO 1 BY -14 DO (* outer loop: 4 digits / loop *) d := 0; (* initialize accumulator & carry *) b := c; REPEAT (* inner loop: radix conversion *) INC(d, f[b] * a); g := b + b - 1; (* denominator previous base *) f[b] := d MOD g; d := d DIV g; (* save carry *) DEC(b); IF b # 0 THEN d := d * b END (* accum. := accum. * num. prev. base *) UNTIL b = 0; WritePaddedInt(e + d DIV a, 4, "0"); (* print previous 4 digits; the leading zeros are significant! *) IF c MOD 196 < 14 THEN Out.Ln END; (* to fit into the System.Log *) e := d MOD a (* saves current 4 digits *) END; Out.Ln END Compute; END PiSpigot4.Compute MODULE PiSpigot; (* Oberon-07 program to compute N digits of π. Compiled with OBNC for the POSIX console (Windows, macOS, Linux). After a C program in the book 'π Unleashed' (p. 81), 2nd ed., 2001, by Jörg Arndt and Christoph Haenel. It uses a 'spigot' algorithm by Rabinowitz & Wagon, as modified by Haenel. The algorithm drips out digits of π, one per loop, as if from a leaky tap, and does not use the digits after they are computed. It only uses INTEGER, no need for floating point or 'bignum'. Based on evaluation of a mathematical series: π = 2 + 1/3(2 + 2/5(2 + 3/7(2 + 4/9(2 + ...)))) in which π can be seen as a number in a number system with a variable base. The 'mixed-radix' base b = (1/3, 2/5, 3/7, 4/9, ...) and now π itself simply is written as an infinite list of 2's. The rest of the algorithm is a radix conversion to the decimal number system. The original algorithm (and a Pascal program) is described in the paper: A Spigot Algorithm for the Digits of π, by Stanley Rabinowitz & Stan Wagon, Amer. Math. Monthly, March 1995, 195-203. https://www.maa.org/sites/default/files/pdf/pubs/amm_supplements/Monthly_Re… Bug fixes for the algorithm and an earlier C program by Christoph Haenel: https://www.jjj.de/hfloat/spigot.haenel.txt For an explanation of how the algorithm works read the above R&W paper, or see the book 'π-Unleashed' by Arndt & Haenel, or see: http://www.pi314.net/eng/goutte.php *) IMPORT Out, Input; CONST N = 20000; (* max. N = 209602 before 'Segmentation fault' *) len = 10*N DIV 3 + 1; (* ?? 10*N + 3 + 1 *) VAR a: ARRAY len OF INTEGER; t: INTEGER; (* time *) PROCEDURE GetClock (): INTEGER; (* Time in seconds *) BEGIN RETURN Input.Time() DIV Input.TimeUnit END GetClock; PROCEDURE Calculate (n: INTEGER); (* Calculate the first n decimal digits of π *) VAR i, p, q, nines: INTEGER; (* number of 9's next to each other *) BEGIN (* ASSERT(n <= N); *) i := 0; p := -1; q := -1; nines := 0; FOR i := 0 TO len - 1 DO a[i] := 2 END; (* fill a[] with 2's *) WHILE n >= 0 DO (* Normalise and compensate for the very first digit *) q := 0; FOR i := len - 1 TO 1 BY -1 DO (* work from right to left *) q := q + 10*a[i]; (* q := carry + 10*a[i] *) a[i] := q MOD (i+i+1); (* a[i] := remainder *) q := q DIV (i+i+1); (* quotient := FLOOR(q/(2*i+1))*i *) q := q * i (* now q = carry *) END; (* The first digit is post-processed *) q := q + 10*a[0]; (* q := carry + 10*a[0] *) a[0] := q MOD 10; q := q DIV 10; (* q: next provisional digit *) IF q = 9 THEN INC(nines) (* q = 9: increment no. of 9's *) ELSE IF p >= 0 THEN Out.Int(p + q DIV 10, 0) END; (* p: previous provis. digit *) IF n < nines THEN nines := n END; (* adjust digits to print *) DEC(n, nines + 1); DEC(nines); WHILE nines >= 0 DO (* print 9's or 0's *) IF q = 10 THEN Out.Int(0, 0) ELSE Out.Int(9, 0) END; DEC(nines) END; nines := 0; IF q = 10 THEN p := 0 ELSE p := q END (* set previous provisional digit *) END END; Out.Ln END Calculate; BEGIN t := GetClock(); Calculate(N); t := GetClock() - t; Out.String("run-time = "); Out.Int(t, 0); Out.String(" s"); Out.Ln END PiSpigot.

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Re (2): DeLOOPing ATADisks.Mod in ETH Oberon 2.3.7.
by peter＠easthope.ca 14 Mar '22

14 Mar '22

> Here a perhaps a slightly more readable code… > ... Thanks. I didn't think to put the first SYSTEM.GET before the loop. ... P. -- mobile: +1 778 951 5147 VoIP: +1 604 670 0140 48.7693 N 123.3053 W

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DeLOOPing ATADisks.Mod in ETH Oberon 2.3.7.
by peter＠easthope.ca 14 Mar '22

14 Mar '22

>From ETH Oberon 2.3.7, PROCEDURE GetKernelCHS(d: LONGINT; VAR chs1: CHS); VAR p, t, i : LONGINT; chs: CHS; BEGIN p := Kernel.bt; i := 0; LOOP SYSTEM.GET(p, t); IF t = -1 THEN EXIT (* end *) ELSIF t = 5 THEN (* HD params *) IF i = d THEN chs.cyls := GetPar(p, 0) + 100H*GetPar(p, 1); chs.hds := GetPar(p, 2); chs.spt := GetPar(p, 14); IF chs.cyls * chs.hds * chs.spt > 0 THEN chs1 := chs END END; INC(i) END; SYSTEM.GET(p+4, t); INC(p, t) END END GetKernelCHS; My revision. PROCEDURE GetKernelCHS(d: LONGINT; VAR chs1: CHS); VAR p, t, i : LONGINT; chs: CHS; BEGIN p := Kernel.bt; i := 0; REPEAT SYSTEM.GET(p, t); IF t # -1 THEN IF t = 5 THEN (* HD params *) IF i = d THEN chs.cyls := GetPar(p, 0) + 100H*GetPar(p, 1); chs.hds := GetPar(p, 2); chs.spt := GetPar(p, 14); IF chs.cyls * chs.hds * chs.spt > 0 THEN chs1 := chs END END; INC(i) END; SYSTEM.GET(p+4, t); INC(p, t) END UNTIL t = -1 END GetKernelCHS; Better way? Criticisms? Thx, ... P. -- mobile: +1 778 951 5147 VoIP: +1 604 670 0140 48.7693 N 123.3053 W

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