TweetFollow Us on Twitter

Apr 86 Letters
Volume Number:2
Issue Number:4
Column Tag:Letters

Letters

Stolen From a Mac?

Erik Westra

Wellington, New Zealand

Your magazine is absolutely fantastic. I find that I can use something from every artical, even though I work mostly in assembler. I hope that the "Electrical Mac" column continues; it's got just the type of info that you can't normally get hold of.

Here's something you might be interested in. While I was poking about in the Mac's ROM, I took a look at the bit of code Steve Jasik mentioned on page 48 of your May 1985 issue. Steve said that the code blasts 32 long words into RAM and then hangs. This is the code he was talking about (on a 512K Mac):

40AD30: LEA $40AD40,A0
 MOVEQ  #$18,D1
40AD36: MOVE.L (40)+,(A1)
 ADDA.W D0,A1
 DBRA D1,$40AD36
 BRA  *-02

Looking at this, I thought that this might be the code that displays the "sad Macintosh" icon on the screen if the system bombs while booting. I displayed the 32 long words at $40AD40 as an icon using a program I'd writen in Kriya's NEON language, and look what I found (displayed at twice it's size):

Maybe the code is called by the RAM based operating system if it finds it's using funny hardware (eg, in a Mac lookalike).

[Our Forth editor, Jörg Langowski, recently paid us a visit here in Placentia while visiting from France, and I showed him Mr. Westra's letter. He was most intrigued and promtly wrote this little stolen icon finder program in Mach 1, the subject of his Threaded Code column this month. The icon is shown at twice it's normal size by this program. Note that the location of this code is different in the new ROMS! A sincere thank you Erik, for sharing this with your US friends. To my knowledge, this has never been revealed! -Ed.]

( demo to get the stolen Apple icon out of the ROM )
( c ) ( J. Langowski 1986 for MacTutor )
( start address of the icon is at $40E132, on a Mac Plus)
( and at $40AD40 on a 512K Mac, found with NOSY 2.0)

hex
variable icon   variable icnrect 4 vallot
40e132 icon !
00800080 icnrect ! 00c000c0 icnrect 4 + ! ( use double size )

: stolen icnrect icon call ploticon ; 
   ( don't know why to use pointer instead of handle for ICON )

Feature Articles?

Paul Devey

Ottawa, Ontario

Mactutor is the best Journal I have seen anywhere for any price. I have waited for years for a journal of your calibur. Please sign me up for a one year subscription as well as all of the back issues. How about sometimes having a feature section or feature issues on different topics such as graphics, sound, I/O etc. Keep up the great work. The only place you should be able to find PHLUFF is between your toes. [This month we feature desk accessories! -Ed.]

Abstract Wanted

William T. Cox

Madison, Wi.

Have you considered offering a subscription to source disks? I have no idea what your demand is, but ( based on the last year) I believe that many people would be intersted. Have you considered offering an index/abstract list for volume 1? A Microsoft File data disk would be a useful offering. A brief abstract or keyord list could be included with each article record. Thanks for a fine magazine! [Maybe the folks at MacBriefs would make us one. -Ed]

Likes Fortran

John Fineout

Duncanville, Tx

Enclosed is my payment for 1986 MacTutor subscription. I depend on your publication heavily to learn insights into programing the Macintosh. I am using Mac Fortran 2.1 forom Microsoft and Macintosh Pascal. I have missed the articles on Fortran in the alast few issues. I have ported several progams from an DEC VAX 11/750 over to the Macintosh with very little problem. I am interested to learn more on how to create a Macintosh environment for input and output for such routines. Other unknowns are how to make use of the keypad and detect tab and enter as a line terminator.

The following Mac Fortran program can be used in substitution for the VAX Fortran time and date system call. It can be made into a subroutine that returns the 23 character time and date sring similar to the VAX. [Note: code below is re-typed from a letter, not pasted from source code as we normally do, so beware. -Ed.]

 Program Time_Date
 Character Months(12)*3,APM*3,datetime*23
 Integer Seconds,MM,DD,YY,L,M
 Real Hours
 Data Months/'JAN','FEB','MAR','APR','MAY','JUN', 
2      'JUL','AUG', 'SEP',''OCT','NOV','DEC'/
 Call Time(Seconds)
 Hours = Seconds/86400.0*24.0
 L = AINT(Hours)
 Mins = (Hours - L)* 60.0
 if (L .gt. 12) then
 APM = ' pm'  
 L = L - 12
 Else
 APM = ' am'
 End if
 Call Date(MM,DD,YY)

 Write(datetime,fmt='I2,A,I2.2,A3,
2     a6,I2,a,A3,a,I2')  L,char(58),Mins,APM,
2     ' Date ',DD,char(45), Months(MM),char(45),YY
 Write (9,100)datetime
100Format ('Time is now ',a23)
 pause
 stop
 end

Maybe this will be helpful to someone. Please deep the Fortran articles coming. [What would be the most help is to convince Microsoft to support and upgrade Fortran to run under HFS on the Mac Plus before 1988, and to make their linker more MDS compatible and bug free. A decent Mac interface would be nice also. And don't forget to mention finishing the parameter glue file support and documentation! -Ed.]

Notes on Basic

Gary Voth

Ontario, Ca

I want to say that I enjy Dave Kelly's fine columns on BASIC programming. BASIC is a favorite language of mine, despite its limitations. I love the interactive pampering that only an interpreted language can give.

However, I spotted an error or two in the January article on using scroll bars from BASIC. I'd like to share the corrections with your readers.

On page 25 the author notes a problem using the BASIC function DEFINT a-z with library calls. To prevent errors from occurring when library routines care called, he recommends defining integer arguments individually (by using the % sign) instead of using the DEFINT statement. Actually, this does prevent the errors, but only by accident!

The reason that calling a bibrary routine creates an error after a DEFINT statement has to do with the way the routines are accessed by BASIC. When a programmer invokes a library routine, such a

CALL  DisposeScroll(ScrID%)

BASIC actually creates a data structure in memory that contains the routine's object code and (in our example) assigns the starting address the variable name "DisposeScroll." Since BASIC's interger data type is 16 bits long, and Macintosh memory locations require at least 24 bits to represent, an error is generated if the variable "DisposeScroll" is defined as an interger (as would be the case after a DEFINT statement)!

It is easy to work around this limitation, however, by designating our llibrary routine names as single-precision (32 bit) variables using the ! sign. This is done in the form below:

            DEFINT a-z
            Call DisposeScroll!(scrID)

Alternatively, you can use the form:

          DEFINT a-z
             DisposeScroll! ScrID

Note that this is essentially the same thing as calling an assembly language routine that has been appended to BASIC the old fashioned way-by POKE-ing it into an array. The array's starting address, as returned by the VARPTR function, can never be forced into an integer:

          DEFINT a-z
             ...
             DisposeScroll!=VARPTR(AsmArray(0)
          CALL DisposeScroll!(ScrID) 

One more note: In the question and answer section the author discusses ways to clear parts of the screen individually without using the CLS function. (By "screen" we of course mean window.) One simple way of doing this that wasn't mentioned is to "paint" with white. Use the Quickdraw call FILLRECT or the BASIC LINE statement to draw a rectangle of white pixels over the section of the window that neds to be erased. For example:

Black% = 33
White% =30
...
LINE(50,50)-(100,100),White%,bf

will erase a section of the current output window 50 pixels square. Of course, the current penmode shold be the default COPY mode. If it has been changed the programmer should restore it with a CALL PENMODE(8) statement.

HFS and Dollars & $ense

Terry A. Ward

Cedar Falls, La

I read with interest the status of commecial software with the HFS file system (vol.2 #1). I noticed that Dollars & $ense is noted as bombing with an insufficient memory message. A quick fix that has worked for me is to reduce the number of desk accessories in the system. By reducing the size of desk accessories from 22,730 bytes to 12,926 I am able to use the product with no problems.

Keep up the great work with MacTutor!

The Max Board!

Mike Carlton

Berkeley, Ca

In the Dec. 1985 issue you have included one of my posts on the MouseHole, concerning the MacMemory board. I would like to make a few corrections now that some new information has come to light. I spoke to some of the MacMemory people at the MacWorld conventionin San Francisco and the told me that the TheMax is NOT compatible with the new ROMs from apple. However, they want to be fair to their customers so they are offering an upgrade, at their cost, to TheMax2. This new board comes; with 2 meg. of RAM and sockets for expansion to 4 meg! All you ned to do is plug in 16 1 meg. chips and you have a 4 meg. Mac. The new board is compatible with the new ROMs; however, if you use the new ROMs, you lose the non-volitable RAM disk.

Anyone with TheMax should contact their dealer. MacMemory is selling the boards to the dealers at cost and asking the dealers to do the upgrade (just a board swap) at no profit. They said prices shold be around $150, but this wasn't finalized.

Friend of MacTutor

Doyle B. Myers

Seattle, Wa

I heard about your "setback" - the loss of your equipment and records from Steve Brecher, my Compu Serve buddy. He suggested that subscribing to MacTutor would be a nice way to help out, and you've got such an impressive reputation with all my fellow developers that I have no problems at all with that. Good luck and keep up the good work! [Thank you very much and to all of our friends and supporters who have expressed their appreciation for our continued publication. -Ed.]

Renewal to ease the pain

Rod Paine

Purcellville, Va

Sorry to learn of your robbery at MacTutor, I hope you're able to put things back together without too much of a loss being sustained.

I know that every little bit can help right now, so I've enclosed a subscription renewal... I think mine is up about August, but in any ccase please add this onto it.

While we only met briefly at the Boston Mac Expo and we'd never be able to pick each other out in a crowd, what you are poviding the readers of MacTutor does maake you stand out... and I'm pleased to be a part of the readership and what MacTutor stands for. [Spoken like a true old-timer! Thanks very much. -Ed.]

Share your technical thoughts on Mac snooping and programming. Write to MacTutor today!

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

DaisyDisk 4.8 - $9.99
DaisyDisk allows you to visualize your disk usage and free up disk space by quickly finding and deleting big unused files. The program scans your disk and displays its content as a sector diagram... Read more
VMware Fusion 11.5.0 - Run Windows apps...
VMware Fusion and Fusion Pro - virtualization software for running Windows, Linux, and other systems on a Mac without rebooting. The latest version includes full support for Windows 10, macOS Mojave... Read more
Apple Configurator 2.10 - Configure and...
Apple Configurator makes it easy to deploy iPad, iPhone, iPod touch, and Apple TV devices in your school or business. Use Apple Configurator to quickly configure large numbers of devices connected to... Read more
Spotify 1.1.15.448. - Stream music, crea...
Spotify is a streaming music service that gives you on-demand access to millions of songs. Whether you like driving rock, silky R&B, or grandiose classical music, Spotify's massive catalogue puts... Read more
MenuMeters 1.9.8 - CPU, memory, disk, an...
MenuMeters is a set of CPU, memory, disk, and network monitoring tools for Mac OS X. Although there are numerous other programs which do the same thing, none had quite the feature set I was looking... Read more
Blocks 3.5.2 - RapidWeaver plug-in; divi...
Blocks is a plugin for RapidWeaver. It allows you to place blocks of text, graphics, and even raw HTML onto your page wherever you like. Drag blocks around, resize them, and even overlap content. All... Read more
Live Home 3D Pro 3.7 - $49.99
Live Home 3D Pro is powerful yet intuitive home design software that lets you build the house of your dreams right on your Mac, iPhone or iPad. It has every feature of Live Home 3D, plus some... Read more
Ableton Live 10.1.1 - Record music using...
Ableton Live lets you create and record music on your Mac. Use digital instruments, pre-recorded sounds, and sampled loops to arrange, produce, and perform your music like never before. Ableton Live... Read more
BetterTouchTool 3.202 - Customize multi-...
BetterTouchTool adds many new, fully customizable gestures to the Magic Mouse, Multi-Touch MacBook trackpad, and Magic Trackpad. These gestures are customizable: Magic Mouse: Pinch in / out (zoom)... Read more
Fission 2.4.6 - Streamlined audio editor...
Fission can crop and trim audio, paste in or join files, or just rapidly split one long file into many. It's streamlined for fast editing. Plus, it works without the quality loss caused by other... Read more

Latest Forum Discussions

See All

Marvel Strike Force is adding Agent Coul...
Marvel Strike Force, the popular squad-based RPG, is set to receive a bunch of new content over the next few weeks. [Read more] | Read more »
Lots of premium games are going free (so...
You may have seen over the past couple weeks a that a bunch of premium games have suddenly become free. This isn’t a mistake, nor is it some last hurrah before Apple Arcade hits, and it’s important to know that these games aren’t actually becoming... | Read more »
Yoozoo Games launches Saint Seiya Awaken...
If you’re into your anime, you’ve probably seen or heard of Saint Seiya. Based on a shonen manga by Masami Kurumada, the series was massively popular in the 1980s – especially in its native Japan. Since then, it’s grown into a franchise of all... | Read more »
Five Nights at Freddy's AR: Special...
Five Nights at Freddy's AR: Special Delivery is a terrifying new nightmare from developer Illumix. Last week, FNAF fans were sent into a frenzy by a short teaser for what we now know to be Special Delivery. Those in the comments were quick to... | Read more »
Rush Rally 3's new live events are...
Last week, Rush Rally 3 got updated with live events, and it’s one of the best things to happen to racing games on mobile. Prior to this update, the game already had multiplayer, but live events are more convenient in the sense that it’s somewhat... | Read more »
Why your free-to-play racer sucks
It’s been this way for a while now, but playing Hot Wheels Infinite Loop really highlights a big issue with free-to-play mobile racing games: They suck. It doesn’t matter if you’re trying going for realism, cart racing, or arcade nonsense, they’re... | Read more »
Steam Link Spotlight - The Banner Saga 3
Steam Link Spotlight is a new feature where we take a look at PC games that play exceptionally well using the Steam Link app. Our last entry talked about Terry Cavanaugh’s incredible Dicey Dungeons. Read about how it’s a great mobile experience... | Read more »
Combo Quest (Games)
Combo Quest 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: Combo Quest is an epic, time tap role-playing adventure. In this unique masterpiece, you are a knight on a heroic quest to retrieve... | Read more »
Hero Emblems (Games)
Hero Emblems 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: ** 25% OFF for a limited time to celebrate the release ** ** Note for iPhone 6 user: If it doesn't run fullscreen on your device... | Read more »
Puzzle Blitz (Games)
Puzzle Blitz 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Puzzle Blitz is a frantic puzzle solving race against the clock! Solve as many puzzles as you can, before time runs out! You have... | Read more »

Price Scanner via MacPrices.net

Get one of Apple’s new 2019 iPhone 11 models...
Boost Mobile is offering the new 2019 Apple iPhone 11, iPhone 11 Pro, and 11 Pro Max for $100 off MSRP. Their discount reduces the cost of an iPhone 11 to $599 for the 64GB models, $899 for the 64GB... Read more
13″ 1.4GHz Silver MacBook Pros on sale for $1...
B&H Photo has new 2019 13″ 1.4GHz 4-Core Touch Bar Silver MacBook Pros on sale for $100 off Apple’s MSRP. Overnight shipping is free to many addresses in the US. These are the same MacBook Pros... Read more
4-core and 6-core 2018 Mac minis available at...
Apple has Certified Refurbished 2018 Mac minis available on their online store for $120-$170 off the cost of new models. Each mini comes with a new outer case plus a standard Apple one-year warranty... Read more
$250 prepaid Visa card with any Apple iPhone,...
Xfinity Mobile will include a free $250 prepaid Visa card with the purchase of any new iPhone, new line activation, and transfer of phone number to Xfinity Mobile. Offer is valid through October 27,... Read more
Sprint is offering the 64GB Apple iPhone 11 P...
Sprint has the new 64GB iPhone 11 Pro available for $12.50 per month for new customers with an eligible trade-in in of iPhone 7 or newer. That’s down from their standard monthly lease of $41.67. The... Read more
Final week: Apple’s 2019 Back to School Promo...
Purchase a new Mac using Apple’s Education discount, and take up to $400 off MSRP. All teachers, students, and staff of any educational institution with a .edu email address qualify for the discount... Read more
Save $30 on Apple’s AirPods at these reseller...
Amazon is offering discounts on new 2019 Apple AirPods ranging up to $30 off MSRP as part of their Labor Day sale. Shipping is free: – AirPods with Charging Case: $144.95 $15 off MSRP – AirPods with... Read more
Preorder your Apple Watch Series 5 today at A...
Amazon has Apple Watch Series 5 GPS models available for preorder and on sale today for $15 off Apple’s MSRP. Shipping is free and starts on September 20th: – 40mm Apple Watch Series 5 GPS: $384.99 $... Read more
21″ iMacs on sale for $100 off Apple’s MSRP,...
B&H Photo has new 21″ Apple iMacs on sale for $100 off MSRP with models available starting at $999. These are the same iMacs offered by Apple in their retail and online stores. Overnight shipping... Read more
2018 4 and 6-Core Mac minis on sale today for...
Apple resellers are offering new 2018 4-Core and 6-Core Mac minis for $100-$150 off MSRP for a limited time. B&H Photo has the new 2018 4-Core and 6-Core Mac minis on sale for up to $150 off... Read more

Jobs Board

*Apple* Mobile Master - Best Buy (United Sta...
**732324BR** **Job Title:** Apple Mobile Master **Job Category:** Store Associates **Location Number:** 000013-Fargo-Store **Job Description:** **What does a Best Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**723452BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Location Number:** 001194-Greeley-Store **Job Description:** At Best Buy, our Read more
Best Buy *Apple* Computing Master - Best Bu...
**731319BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Store Associates **Location Number:** 000303-Arlington Heights-Store **Job Read more
Best Buy *Apple* Computing Master - Best Bu...
**733266BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Sales **Location Number:** 000144-Union City-Store **Job Description:** **What does a Read more
Geek Squad *Apple* Master Consultation Agen...
**732907BR** **Job Title:** Geek Squad Apple Master Consultation Agent **Job Category:** Services/Installation/Repair **Location Number:** 000360-Williston-Store Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.