May 2017 - Oberon - mailman3.inf.ethz.ch

O-07 .rsc file layout.
by Jan de Kruyf 16 May '17

16 May '17

Hallo, Does anybody have the layout description of the risc code files that ORP.Compile produces? Apparently it has changed from 2013. (the date of the ORTool.Mod) ------------------------ norebo ORTool.DecSym ORTool.rsc ORTool 18.2.2013 OR-decode ORTool.rsc �n� D8006C6F 0 bad symfile version ------------------------- Thanks, Bye Jan.

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What do you use for threads/coroutines?
by noreply＠z505.com 15 May '17

15 May '17

This probably has been discussed somewhere before.. What do componentpascal (and Oberon) developers use to prevent an application from hanging? In delphi one starts a new thread... C++ is similar.. Does Componentpascal/Oberon have some module that covers this? Calls windows threads with a callback function? Does it have some coroutine module? At what point does one have to start modifying the language itself if writing a module won't cut it? Sorry if this has been answered before. A quick search on google provided not much. A common case for an application hanging might be if you have a progress bar and you do not put it into a separate thread, or a status memo/editarea/editbox that is written to constantly, but you want to continue the application while the memo messages are written. And when not using threads, Delphi has something called Application.ProcessMessages which sort of fakes making a thread without being an actual thread, and let's the application respond even though normally it would hang. Oberon/ComponentPascal has something similar?

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Modulus on negative number
by Srinivas Nayak 15 May '17

15 May '17

Dear All, Recently I come across modulus on a negative number. Will it produce a negative number or positive? Someone says both are correct! http://stackoverflow.com/a/4403556 Which one is mathematically correct? Surprisingly different languages calculate it differently even! What is Oberon's way? With thanks and best regards, Yours sincerely, Srinivas Nayak Home: http://www.mathmeth.com/sn/ Blog: http://srinivas-nayak.blogspot.in/

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Oberon circuit designer?
by Travis Ayres 13 May '17

13 May '17

I've seen screen captures of a circuit designer with Oberon; does anyone have more information on it or know where I could find It? Thanks!

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Modulus on negative number
by Andreas Pirklbauer 13 May '17

13 May '17

Other languages have avoided the problem of undefined values by defining a remainder rather than a modulo operator. For example, in Swift (*) we have: "The remainder operator (a % b) works out how many multiples of b will fit inside a and returns the value that is left over (known as the remainder). To determine the answer for a % b, the % operator calculates the following equation and returns remainder as its output: a = (b x some multiplier) + remainder where some multiplier is the largest number of multiples of b that will fit inside a. The sign of b is ignored for negative values of b. This means that a % b and a % -b always give the same answer. Note: The remainder operator (%) is also known as a modulo operator in other languages. However, its behavior in Swift for negative numbers means that it is, strictly speaking, a remainder rather than a modulo operation." Examples: 1 % -12 = 1 % 12 = 1 -1 % -12 = -1 % 12 = -1 (*) https://developer.apple.com/library/content/documentation/Swift/Conceptual/… —————————————— > Jörg joerg.straube(a)iaeth.ch Sat May 11 11:13:19 CEST 2017 > Hi, > Just for completeness, the result should be > 1 MOD -12 = -11 > -1 MOD -12 = -1 > > Jörg > Am 13.05.2017 um 10:12 schrieb Peter Matthias <PeterMatthias at web.de <https://lists.inf.ethz.ch/mailman/listinfo/oberon>>: > > Agreed. However, -1 MOD -12 or 1 MOD -12 is not defined in Oberon. > > > Am 12.05.2017 um 22:43 schrieb Aubrey McIntosh: >> for -1 MOD 12, the mathematically correct answers which are consistent >> with the language report, are >> q=-1, r=11. >> >> This definition works very well, for example, to implement wrap around >> strip chart displays. >> >> >> On Fri, May 12, 2017 at 2:28 PM, Peter Matthias <PeterMatthias at web.de <https://lists.inf.ethz.ch/mailman/listinfo/oberon> >> <mailto:PeterMatthias at web.de <https://lists.inf.ethz.ch/mailman/listinfo/oberon>>> wrote: >> >> Warming up the thread to give supposedly correct answer: >> >> Am 16.02.2017 um 00:00 schrieb Peter Matthias: >> >> >> >> Am 15.02.2017 um 04:21 schrieb Srinivas Nayak: >> >> Dear All, >> >> Recently I come across modulus on a negative number. >> Will it produce a negative number or positive? >> Someone says both are correct! >> http://stackoverflow.com/a/4403556 <http://stackoverflow.com/a/4403556> >> <http://stackoverflow.com/a/4403556 <http://stackoverflow.com/a/4403556>> >> Which one is mathematically correct? >> Surprisingly different languages calculate it differently even! >> What is Oberon's way? >> >> >> The theory was already answered. In practice, all compiler >> implementations I used (native X86, Shark, MIPS), give wrong >> result when >> both, divident and divisor are negative. I fixed it just >> yesterday for >> all non x86 versions. >> >> >> I should have read the language report before making such claims. >> >> Oberon Report says: >> >> "The operators DIV and MOD apply to integer operands only. They are >> related by the following formulas defined for any dividend x and >> positive divisors y: >> x = (x DIV y) * y + (x MOD y) >> 0 ≤ (x MOD y) < y" >> >> Oberon07-Report says: >> >> "The operators DIV and MOD apply to integer operands only. Let q = x >> DIV y, and r = x MOD y. >> Then quotient q and remainder r are defined by the equation >> x = q*y + r 0 <= r < y" >> >> Last statement obviously cannot be met if y is negative. >> >> So in short: Don't use DIV/MOD for negative divisors as the result >> is not defined. >> >> >From the implemtation point of view this perfectly makes sense as >> negative divisors are seldom used and correction for DIV of the >> usually stupid hardware implementation only takes 3 additional >> instructions compared to at least 6 for a complete definition. >> Simple SHIFT/AND instructions for power of 2 divisors easily >> outwight these 3 additional instructions. >> >> >> Peter >> >> -- >> Oberon at lists.inf.ethz.ch <https://lists.inf.ethz.ch/mailman/listinfo/oberon> <mailto:Oberon at lists.inf.ethz.ch <https://lists.inf.ethz.ch/mailman/listinfo/oberon>> mailing >> list for ETH Oberon and related systems >> https://lists.inf.ethz.ch/mailman/listinfo/oberon <https://lists.inf.ethz.ch/mailman/listinfo/oberon> >> <https://lists.inf.ethz.ch/mailman/listinfo/oberon <https://lists.inf.ethz.ch/mailman/listinfo/oberon>> >> >> >> >> >> -- >> Aubrey McIntosh, Ph.D. >> 1502 Devon Circle >> Austin TX 78723 >> (512) 348-7401 >> >>

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Various Linux based Oberon systems: up calls.
by eas lab 04 May '17

04 May '17

NW's term "up call" seems better than the current "call back" description, because it recognises the heirarchy. I.e. that the Oberon is a descendant of the linux, that it's riding on. Apparently LNO & Linux ETHO Oberon have hidden the details of how their ETHO systems interface with linux? Since PO13 exposes all, from the hardware up, it can't hide any implementation details? I can't find my backup of my stolen systems PO13 docos right now, but since PO13 is independant of any other OS, it wouldn't tell me how to connect LNO to the underlying <tcp sockets> ? Does PO13 have Inet capability? LNO seems to be unique in the Oberon family, in offering a Linux based version that is also independant of the massive X11 system. FrameBuffer based LNO is very good on a USBstik-based Linux:TinyCore. Also there are simple haks to help with LNO's problem of not easily being able to navigate the file tree - outside of its own directory. Linux ETHO Oberon <up calls> in 2 usefull ways: 1. System.Execute <any linux command. 2. All the modem-internet facilities that we had with Native-Oberon just "take" a connection/socket from [ the parent] Linux. Does V4 perhaps expose how it "connects" to its linux "parent"? == TIA.

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Fw: FPGA - Bitmap Paint Horizontal Line
by Tomas Kral 04 May '17

04 May '17

Hi, EDIT - code correction I arrived at coding this, it may not be correct, but does things on $AAAAA$ patterns. PROCEDURE PaintHLine(x, src, dst, w: INTEGER); VAR bt: BYTE; wd: INTEGER; pix: SET; BEGIN (* (pix * {maskleft*8..31} * {0..maskright*8-1}) *) WHILE w > 0 DO (* this part modified from Display.Mod:CopyPattern *) SYSTEM.GET(src, bt); wd := bt; INC(src); DEC(w, 8); IF w > 0 THEN SYSTEM.GET(src, bt); wd := wd + bt*100H; INC(src); DEC(w, 8); IF w > 0 THEN SYSTEM.GET(src, bt); wd := wd + bt*10000H; INC(src); DEC(w, 8); IF w > 0 THEN SYSTEM.GET(src, bt); wd := wd + bt*1000000H; INC(src); DE C(w, 8) END END END; SYSTEM.GET(dst, pix); SYSTEM.PUT(dst, SYSTEM.VAL(SET, LSL(wd, x MOD 32)) + pix); INC(dst, 4); SYSTEM.GET(dst, pix); wd := ROR(wd, -(x MOD 32)); SYSTEM.PUT(dst, SYSTEM.VAL(SET, wd)*{0..x MOD 32-1} + pix); (* Texts.WriteInt(Wr, w, 6); Texts.WriteLn(Wr) *) END END PaintHLine; Comments: [a] it now reflects x coordinate, but works only with w*8, need to deal with a remaining bits w MOD 8, as the last step [b] bits shifted left in memory, appears shifted right on display, interestingly also vice versa, as if on reflection in the mirror [c] need to somehow unroll the loop into three parts for speed improvement as suggested, as is, it needs four byte reads from source, two word read/writes per iteration INC(dst,4), but how? [d] bt*100H is defacto shift 8 operation, why normal ASR/LSL were not used instead, how many RISC cycles they got? Tomas On Sun, 30 Apr 2017 17:45:08 +0200 Jörg <joerg.straube(a)iaeth.ch> wrote: > Hi Tomas > > One possibilty is to split your algorithm in three parts > 1) handle the left border (max 31 bit) until you reach a multiple of > 32 bit 2) then copy n words (32 bit) > 3) handle the right border = remaining bits up to the width "w" > > Jörg > > > Am 30.04.2017 um 16:33 schrieb Tomas Kral <thomas.kral(a)email.cz>: > > > > Chris, Joerg, > > > > Learning, not doing much useful bitmap examples. > > > > I was surprised to realise, Bitmaps are easy to be copied/displayed, > > by lines, after each line destination address is incremented by 128 > > bytes per display line, source address by bitmap width DIV 8, lines > > h decremented by 1. > > > > This works nicely on any bitmap of widths multiple of > > 32 bits accross. 32xN, 64xN, etc, and must be aligned horizontally > > also on 32 bit as well, for x=0,32,64,.. coordinate (x,y = top > > left). Bitmaps are drawn upwards. > > > > (* paints horizontal bitmap line, for x,w=32,64,... *) > > PROCEDURE PaintHLine(src, dst, w: INTEGER); > > VAR s,t: SET; > > BEGIN > > w := (w+7) DIV 8; (* bytes per bitmap line *) > > WHILE w > 0 DO > > SYSTEM.GET(src, t); SYSTEM.GET(dst, s); > > SYSTEM.PUT(dst, s + t); > > INC(dst, 4); INC(src, 4); DEC(w, 4) > > END > > END PaintHLine; > > > > I am looking into a solution where x can spill over byte boundary, > > also width of finer bitwise granularity. > > > > I did a similar exercise in assembly many, many years ago on 8-bit > > computers. > > > > Tomas > > > > > > On Sun, 30 Apr 2017 21:26:09 +0930 > > Chris Burrows <chris(a)cfbsoftware.com> wrote: > > > >>> -----Original Message----- > >>> From: Oberon [mailto:oberon-bounces@lists.inf.ethz.ch] On Behalf > >>> Of Tomas Kral > >>> Sent: Sunday, 30 April 2017 8:05 PM > >>> To: oberon(a)lists.inf.ethz.ch > >>> Subject: Re: [Oberon] FPGA - SET initialisation > >>> > >>> Ah yes, sily me. > >>> > >>> But how to best initialise a SET variable with an arbitrary byte / > >>> integer? > >>> > >>> TYPE ii = POINTER TO iidsc; > >>> iidsc = STRUCT i: INTEGER END; > >>> > >>> i := b; SYSTEM.PUT(ii,i); SYSTEM.GET(ii,s); (* initialise a set > >>> with a byte *) SYSTEM.PUT(ii,i); SYSTEM.GET(ii,s); (* initialise > >>> a set with an integer > >>> *) > >>> > >> > >> Do you mean how do you typecast an INTEGER / BYTE variable to a SET > >> variable? > >> > >> If so then: > >> > >> VAR > >> s: SET; > >> i: INTEGER; > >> b: BYTE; > >> > >> BEGIN > >> s := SYSTEM.VAL(SET, i); > >> s := SYSTEM.VAL(SET, ORD(b)) > >> > >> I'm curious. What is it that you are trying to do that makes you > >> ask this question? > >> > >> Regards, > >> Chris Burrows > >> CFB Software > >> http://www.astrobe.com/RISC5 > >> > >> -- > >> Oberon(a)lists.inf.ethz.ch mailing list for ETH Oberon and related > >> systems https://lists.inf.ethz.ch/mailman/listinfo/oberon > > > > -- > > Oberon(a)lists.inf.ethz.ch mailing list for ETH Oberon and related > > systems https://lists.inf.ethz.ch/mailman/listinfo/oberon > -- > Oberon(a)lists.inf.ethz.ch mailing list for ETH Oberon and related > systems https://lists.inf.ethz.ch/mailman/listinfo/oberon -- Tomas Kral <thomas.kral(a)email.cz> -- Oberon(a)lists.inf.ethz.ch mailing list for ETH Oberon and related systems https://lists.inf.ethz.ch/mailman/listinfo/oberon -- Tomas Kral <thomas.kral(a)email.cz>

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FPGA - ASR shift operator
by Tomas Kral 01 May '17

01 May '17

Hi, Looking at shift operators (functions) on Oberon system code, I do not understand why ASR(m, -n) takes a negative argument? Tomas -- Tomas Kral <thomas.kral(a)email.cz>

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Are shortCuts allowed?
by eas lab 01 May '17

01 May '17

Have I overlooked any good reason why <FN> should NOT System.Store the TextFrame that received the last KeyStroke? For complex jobs, where you are reading previous Log : A and comparing text/code in Frame : B with text/code in Frame : C, while writing the new report in Frame : D, and constructing text/code in Frame : E, from B & C; the user will want to make frequent FilesSaves, to be able to recover from likely mistakes. Ie. the frequency of System.Store to KeyStroke is higher than anticipated in the original design. So that it's much more efficient to just <hit a F-key> to System.Store than reach for the mouse. Computing is not about computers; it's about HCI. [linux] wily, which is derived from ETHO has made a number of enhancements: adjustable frame-width & add/delete extra tracks; but also doesn't include my above suggestion.

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