TweetFollow Us on Twitter

Time Retrieval
Volume Number:5
Issue Number:1
Column Tag:Basic School

Related Info: Time Manager

Time Retrieval and Storage Techniques

By Dave Kelly, MacTutor Editorial Board

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

Time Retrieval and Storage Techniques

It’s only a matter of time. Anybody see the ad for the MacTutor of the future in the November, 1988 MacTutor? The ad may sound like a joke about the 100th anniversary of MacTutor, but some of the “future” has already been invented. I did some thought on the subject of the Basic School column described in the ad, which is also the title of this column. There are two basic subjects implied by the title, time retrieval and time storage.

From a philosophical point of view you may ask, how can time be saved or retrieved? Looking at the answer from that perspective would lead us to a discussion of Einstein and his theory of relativity which is beyond the scope and intent of this column. Instead let’s look at some ways which we can use time to our advantage and see how storage and retrieval fits into the scheme of things.

From a user level on the Macintosh there is one time retrieval/storage mechanism that is accessible to all “the rest of us”. The example I refer to is the Alarm mechanism built into the clock chip. The date and time setting is copied (“retrieved”) at system startup from the clock chip into its own low-memory location. It’s stored there as the number of seconds since midnight, January 1, 1904, and is updated every second. The range of the clock chip is from January 1, 1904 through February 6, 2040 (does that mean that 51 years from now I’ll need to replace my clock chip?). The low-memory location can be access by your program. BASIC (every brand) includes its own time retrieval command. In True Basic the TIME and TIME$ functions are provided. TIME returns the number of seconds since midnight in tenths of seconds. The TIME$ function returns a string that contains the time as measured by the 24-hour clock with resolution in seconds. ZBasic and MS QuickBASIC uses the TIMER function which returns the seconds since midnight (similar to the True Basic TIME function) and TIME$ which works the same as in True Basic. The problem is that the TIMER function does not provide enough resolution. At least the True Basic TIME function provided tenths of seconds or better resolution. Since we know that other languages are able to access the time in greater resolution, we may use the same function (ROM) to retrieve the time in greater resolution. This is especially important for benchmark tests where two compiled programs are being timed and the difference is tenths of seconds or better. In benchmarks that have been done in the past, sometimes the TIME function was used and there was rounding off to either 0 or 1 second. A program running in 0 seconds is absurd, but that was the best we could do with MS Basic at the time. QuickBASIC and ZBasic both allow access to the TickCount call (Macintosh ROM). In QuickBASIC a typical benchmark might be implemented such as:

Figure 1. The Time Machine

First initialize the ToolBox routine:

TOOLBOX “I”

This must be used before any other ToolBox statement in the program. Now define a sub program or routine that can be called to replace the other time functions usually used in the benchmark.

SUB Tick (Count&) STATIC
TrapNo% = &HA975
Count& = 0&  : ‘Define the variable
ToolBox “L”, TrapNo%, Count&
END SUB

Now call Tick(Count&) whenever you need the time. A tick is one-sixtieth of a second, enough for the tenth of a second accuracy provided by True BASIC’s function. In ZBasic it is even easier to call TickCount. In ZBasic just use the function directly:

Count&=FN TICKCOUNT

As you can see, accessing real time is really the simple part of the job. Accessing stored time is another aspect. I’ll leave the subject of how the stored time became stored for later except to say that the Parameter RAM also stores the alarm setting. You can set the alarm with the Alarm Clock DA (included with your system software).

The Analog Alarm Clock program included here demonstrates how you can retrieve the stored alarm time from the low-memory area. The Alarm time is stored at $200. The getAlarm routine retrieves the time by peeking at memory directly. The result is then converted to date information via the secs2date toolbox routine. The Analog Clock program reveals some problems. The date conversion library routines are used to convert seconds to dates and dates to seconds. Secs2Date works fine, but there is a problem with the Date2Secs routine. This means that the Date2Secs routine must be called a different way. Fortunately, QuickBASIC provides the ToolBox call which allows you to make ROM calls yourself. The following lines replace the Date2Secs library routine:

ToolBox “I”

...   (Don’t forget to initialize the toolbox)


TrapNo%=&HA9C7
ToolBox “R”, TrapNo%, ReturnArray&(0),VARPTR(DtRec%(0))
Al&=ReturnArray&(2)

It’s unfortunate that we have to go through that trouble, but that’s just the way it goes. I confess it took awhile before I realized that I wasn’t going to be able to get it to work without the ToolBox library call.

In the program, alarm time is taken from parameter RAM and then it’s updated when changed when the alarm is turned on. Be careful when poking around the parameter RAM. If the wrong parameter gets changed you may have to Zap the parameter RAM to get started. You can do this by removing your MacPlus battery for a few minutes when your power is off or by holding down command-option when opening the control panel on newer Mac systems.

Flashing the menu bar like the Alarm Clock DA does will be left for another day. Anybody know how to do that from Basic? What I’m not sure of is where the alarm status is stored. Happy New Year!

‘Analog Alarm Clock Program
‘©1989 MacTutor
‘by Dave Kelly

DIM DtRec%(6),CenterRect%(3),pattern%(3)
ToolBox “I”
DIM ReturnArray&(5)
GOSUB getAlarm
false=0:true=NOT false
PI=3.14159

‘Set up menus
MENU 1,0,1,”File”
MENU 1,1,1,”Turn Alarm On ”
MENU 1,2,0,”-”
MENU 1,3,1,”Quit”
CmdKey 1,3,”Q”

‘ Get Screen size
sheight=SYSTEM(6)
swidth=SYSTEM(5)
WINDOW 1,”Analog Alarm Clock”,(4,44)-(swidth-4,sheight-4),6

‘Find the center of the window, centerx%,centery%
‘ This should work with any size of screen
wheight%=WINDOW(3)
wwidth%=WINDOW(2)
centerx%=wwidth%/2
centery%=wheight%/2
circledia=centery%-25
GOSUB SetupClock
ON MENU GOSUB MenuEvent
ON DIALOG GOSUB DialogEvent
DIALOG ON:MENU ON

Loop:
forecolor 33:’ change color to black
t$=TIME$:’ Get the current time and separate into variables
hour$=LEFT$(t$,2)
Min$=MID$(t$,4,2)
Sec$=RIGHT$(t$,2)
H=VAL(hour$):M=VAL(Min$):S=VAL(Sec$)
IF H>12 THEN H=H-12
H=H+M/60

‘ Compute the angles for each hand of the clock
SecAngle=(360-S*6)*PI/180
MinAngle=(360-M*6)*PI/180
HAngle=(360-H*30)*PI/180

‘Draw the second hand
CALL MOVETO (centerx%,centery%)
ypoint=(circledia*COS(SecAngle))*.98
xpoint=(circledia*SIN(SecAngle))*.98
CALL LINE (-xpoint,-ypoint)
IF SecAngle<>OldSec THEN
    CALL MOVETO (centerx%,centery%)
    CALL PENMODE (11)
    ypoint=(circledia*COS(OldSec))*.98
    xpoint=(circledia*SIN(OldSec))*.98
    CALL LINE (-xpoint,-ypoint)
    CALL PENMODE(8)
END IF

‘Draw the minute hand
CALL PENSIZE(2,2)
CALL MOVETO (centerx%,centery%)
ypoint=(circledia*COS(MinAngle))*.9
xpoint=(circledia*SIN(MinAngle))*.9
CALL LINE (-xpoint,-ypoint)
IF MinAngle<>OldMin THEN
    CALL MOVETO (centerx%,centery%)
    CALL PENMODE (11)
    ypoint=(circledia*COS(OldMin))*.9
    xpoint=(circledia*SIN(OldMin))*.9
    CALL LINE (-xpoint,-ypoint)
    CALL PENMODE(8)
END IF

‘Draw the hour hand
CALL PENSIZE(4,4)
CALL MOVETO (centerx%,centery%)
ypoint=(circledia/2*COS(HAngle))
xpoint=(circledia/2*SIN(HAngle))
CALL LINE (-xpoint,-ypoint)
IF MinAngle<>OldMin THEN
    CALL MOVETO (centerx%,centery%)
    CALL PENMODE (11)
    ypoint=(circledia/2*COS(OldH))
    xpoint=(circledia/2*SIN(OldH))
    CALL LINE (-xpoint,-ypoint)
    CALL PENMODE(8)
END IF
CALL PENSIZE(1,1)

forecolor 205:’ Change color to red
LOCATE 1,1:PRINT “AlarmTime: “;AlarmTime$
forecolor 33:’ Change color to black
LOCATE 2,1:PRINT “Current Time: “;t$
CALL TEXTMODE(0)
OldT$=t$:OldSec=SecAngle:OldMin=MinAngle:OldH=HAngle
CALL FILLOVAL(VARPTR(CenterRect%(0)),VARPTR(pattern%(0)))
IF Alrm=false THEN
    forecolor 273
    LOCATE 3,1:PRINT “Alarm is off”:GOTO Loop
END IF
forecolor 341:’Change color to Green
LOCATE 3,1:PRINT “Alarm is on “
‘Sound the alarm if time is up!
IF t$=AlarmTime$ THEN
    BEEP:BEEP:BEEP
    LOCATE 4,1:PRINT “Alarm event occurred”
END IF
GOTO Loop
DIALOG OFF

SetupClock:’ Set up the face of the clock
activewindow=WINDOW(0)
WINDOW OUTPUT 1
CALL TEXTSIZE(14)
CALL MOVETO(centerx%-8,centery%-circledia-4):PRINT “12”;
CALL MOVETO(centerx%-8,centery%+circledia+20):PRINT “ 6”;
CALL MOVETO(centerx%-circledia-20,centery%+7):PRINT “9”;
CALL MOVETO(centerx%+circledia+10,centery%+7):PRINT “3”;
PSET (centerx%,centery%)
forecolor 205:’ Change color to red
CALL PENSIZE(2,2)
CIRCLE (centerx%,centery%),circledia
CALL PENSIZE(1,1)
SetRect CenterRect%(0),centerx%-5,centery%-5,centerx%+5,centery%+5
forecolor 33:’ Change color to black
SetRect pattern%(0),&HFFFF,&HFFFF,&HFFFF,&HFFFF
CALL FILLOVAL(VARPTR(CenterRect%(0)),VARPTR(pattern%(0)))
WINDOW OUTPUT activewindow
RETURN

DialogEvent:
d=DIALOG(0)
SELECT CASE d
    CASE 1
        IF DIALOG(1)=1 THEN editwindow=true
    CASE 4
        GOTO Quit
    CASE 5
        IF DIALOG(5)=1 THEN GOSUB SetupClock
    CASE ELSE
END SELECT
RETURN

MenuEvent:
menunumber=MENU(0)
menuitem=MENU(1)
MENU
IF menunumber=1 THEN
    IF menuitem=1 THEN GOSUB SetAlarm
    IF menuitem=3 THEN Quit
END IF
RETURN

SetAlarm:’ Set the alarm
Alrm=NOT Alrm
DoSet:
IF Alrm THEN
    MENU 1,1,1,”Turn Alarm Off”
    WINDOW 2,””,(50,50)-(250,150),2
    LOCATE 2,1:PRINT “Alarm Time:”
    IF AlarmTime$=”” THEN AlarmTime$=TIME$
    EDIT FIELD 1,AlarmTime$,(100,17)-(165,32),1
    BUTTON 1,1,”OK”,(40,45)-(170,75),1
    editwindow=false
    WHILE editwindow=false
    WEND
    AlarmTime$=EDIT$(1)
    a$=””:i=1
    WHILE MID$(AlarmTime$,i,1)<>”:”
        a$=a$+MID$(AlarmTime$,i,1)
        i=i+1
    WEND
    Ahour=VAL(a$)
    IF Ahour>24 OR Ahour<0 THEN GOTO DoSet
    a$=””
    i=i+1
    WHILE MID$(AlarmTime$,i,1)<>”:”
        a$=a$+MID$(AlarmTime$,i,1)
        i=i+1
    WEND
    Amin=VAL(a$)
    IF Amin>59 OR Amin<0 THEN GOTO DoSet
    a$=””
    i=i+1
WHILE i<=LEN(AlarmTime$)
        a$=a$+MID$(AlarmTime$,i,1)
        i=i+1
WEND
Asec=VAL(a$)
IF Asec>59 OR Asec<0 THEN GOTO DoSet
a$=””
IF Ahour<10 THEN a$=”0"+STR$(Ahour) ELSE a$=STR$(Ahour)
a$=a$+”:”
IF Amin<10 THEN a$=a$+”0"+STR$(Amin) ELSE a$=a$+STR$(Amin)
a$=a$+”:”
IF Asec<10 THEN a$=a$+”0"+STR$(Asec) ELSE a$=a$+STR$(Asec)
AlarmTime$=””
FOR i=1 TO LEN(a$)
    IF MID$(a$,i,1)<>” “ THEN AlarmTime$=AlarmTime$+MID$(a$,i,1)
NEXT i
DtRec%(3)=Ahour
DtRec%(4)=Amin
DtRec%(5)=Asec
‘Call Date2secs routine (QuickBASIC Date2secs does not work right)
TrapNo%=&HA9C7
ToolBox “R”, TrapNo%, ReturnArray&(0),VARPTR(DtRec%(0))
Al&=ReturnArray&(2)
POKEL &H200, Al&
    WINDOW CLOSE 2
ELSE
    TEXTMODE (0):LOCATE 2,1:PRINT”                                   
     “
    MENU 1,1,1,”Turn Alarm On ”
END IF
RETURN

getAlarm:’ Retrieve
Al&= PEEKL(&H200)
secs2Date Al&,DtRec%(0)
a$=””
IF DtRec%(3)<10 THEN a$=”0"+STR$(DtRec%(3)) ELSE a$=STR$(DtRec%(3))
a$=a$+”:”
IF DtRec%(4)<10 THEN a$=a$+”0"+STR$(DtRec%(4)) ELSE a$=a$+STR$(DtRec%(4))
a$=a$+”:”
IF DtRec%(5)<10 THEN a$=a$+”0"+STR$(DtRec%(5)) ELSE a$=a$+STR$(DtRec%(5))
AlarmTime$=””
FOR i=1 TO LEN(a$)
    IF MID$(a$,i,1)<>” “ THEN AlarmTime$=AlarmTime$+MID$(a$,i,1)
NEXT i
RETURN

Quit:
WINDOW CLOSE 1
END

 
AAPL
$524.94
Apple Inc.
+5.93
MSFT
$40.01
Microsoft Corpora
-0.39
GOOG
$536.10
Google Inc.
-20.44

MacTech Search:
Community Search:

Software Updates via MacUpdate

Mac DVDRipper Pro 4.1.7 - Copy, backup,...
Mac DVDRipper Pro is the DVD backup solution that lets you protect your DVDs from scratches, save your batteries by reading your movies from your hard disk, manage your collection with just a few... Read more
PDFpenPro 6.2 - Advanced PDF toolkit for...
PDFpenPro allows users to edit PDF's easily. Add text, images and signatures. Fill out PDF forms. Merge or split PDF documents. Reorder and delete pages. Even correct text and edit graphics! Create... Read more
PDFpen 6.2 - Edit and annotate PDFs with...
PDFpen allows users to easily edit PDF's. Add text, images and signatures. Fill out PDF forms. Merge or split PDF documents. Reorder and delete pages. Even correct text and edit graphics! Features... Read more
Monolingual 1.5.9 - Remove unwanted OS X...
Monolingual is a program for removing unnecesary language resources from OS X, in order to reclaim several hundred megabytes of disk space. It requires a 64-bit capable Intel-based Mac and at least... Read more
Maya 2015 - Professional 3D modeling and...
Maya is an award-winning software and powerful, integrated 3D modeling, animation, visual effects, and rendering solution. Because Maya is based on an open architecture, all your work can be scripted... Read more
Starcraft II: Wings of Liberty 1.1.1.180...
Download the patch by launching the Starcraft II game and downloading it through the Battle.net connection within the app. Starcraft II: Wings of Liberty is a strategy game played in real-time. You... Read more
Sibelius 7.5.0 - Music notation solution...
Sibelius is the world's best-selling music notation software for Mac. It is as intuitive to use as a pen, yet so powerful that it does most things in less than the blink of an eye. The demo includes... Read more
Typinator 5.9 - Speedy and reliable text...
Typinator turbo-charges your typing productivity. Type a little. Typinator does the rest. We've all faced projects that require repetitive typing tasks. With Typinator, you can store commonly used... Read more
MYStuff Pro 2.0.16 - Create inventories...
MYStuff Pro is the most flexible way to create detail-rich inventories for your home or small business. Add items to MYStuff by dragging and dropping existing information, uploading new images, or... Read more
TurboTax 2013.r17.002 - Manage your 2013...
TurboTax guides you through your tax return step by step, does all the calculations, and checks your return for errors and overlooked deductions. It lets you file your return electronically to get... Read more

Latest Forum Discussions

See All

Have a Special Dead Trigger 2 Easter Bas...
Have a Special Dead Trigger 2 Easter Basket Full of Goodies, Courtesy of Madfinger Games Posted by Rob Rich on April 18th, 2014 [ permalink ] Dead Trigger 2 | Read more »
Zynga Launches Brand New Farmville Exper...
Zynga Launches Brand New Farmville Experience with Farmville 2: Country Escape Posted by Tre Lawrence on April 18th, 2014 [ permalink ] | Read more »
David. Review
David. Review By Cata Modorcea on April 18th, 2014 Our Rating: :: MINIMALISTIC IN A DIFFERENT WAYUniversal App - Designed for iPhone and iPad David is a minimalistic game wrapped inside of a soothing atmosphere in which the hero... | Read more »
Eyefi Unveils New Eyefi Cloud Service Th...
Eyefi Unveils New Eyefi Cloud Service That Allows Users to Share Media Across Personal Devices Posted by Tre Lawrence on April 18th, 2014 [ permalink ] | Read more »
Tales from the Dragon Mountain: The Lair...
Tales from the Dragon Mountain: The Lair Review By Jennifer Allen on April 18th, 2014 Our Rating: :: STEADY ADVENTURINGiPad Only App - Designed for the iPad Treading a safe path, Tales from the Dragon Mountain: The Lair is a... | Read more »
Yahoo Updates Flickr App with Advanced E...
Yahoo Updates Flickr App with Advanced Editing Features and More Posted by Tre Lawrence on April 18th, 2014 [ permalink ] | Read more »
My Incredible Body - A Kid's App to...
My Incredible Body - A Kid's App to Learn about the Human Body 1.1.00 Device: iOS Universal Category: Education Price: $2.99, Version: 1.1.00 (iTunes) Description: Wouldn’t it be cool to look inside yourself and see what was going on... | Read more »
Trials Frontier Review
Trials Frontier Review By Carter Dotson on April 18th, 2014 Our Rating: :: A ROUGH LANDINGUniversal App - Designed for iPhone and iPad Trials Frontier finally brings the famed stunt racing franchise to mobile, but how much does its... | Read more »
Evernote Business Notebook by Moleskin I...
Evernote Business Notebook by Moleskin Introduced – Support Available in Evernote for iOS Posted by Tre Lawrence on April 18th, 2014 [ permalink ] | Read more »
Sparkle Unleashed Review
Sparkle Unleashed Review By Jennifer Allen on April 18th, 2014 Our Rating: :: CLASSY MARBLE FLINGINGUniversal App - Designed for iPhone and iPad It’s a concept we’ve seen before, but Sparkle Unleashed is a solidly enjoyable orb... | Read more »

Price Scanner via MacPrices.net

iMacs on sale for up to $160 off MSRP this we...
Best Buy has iMacs on sale for up to $160 off MSRP for a limited time. Choose free home shipping or free instant local store pickup (if available). Prices are valid for online orders only, in-store... Read more
iPad Airs on sale this weekend for up to $100...
Best Buy has WiFi iPad Airs on sale for $50 off MSRP and WiFi + Cellular iPad Airs on sale for $100 off MSRP on their online store for a limited time, with prices now starting at $449. Choose free... Read more
Apple restocks refurbished Mac minis starting...
The Apple Store has restocked Apple Certified Refurbished Mac minis for up to $150 off the cost of new models. Apple’s one-year warranty is included with each mini, and shipping is free: - 2.5GHz Mac... Read more
Hyundai Brings Apple CarPlay To The 2015 Sona...
Hyundai Motor America has announced it will bring Apple CarPlay functionality to the 2015 Sonata. CarPlay is pitched as a smarter, safer and easier way to use iPhone in the car and gives iPhone users... Read more
Updated iPads Coming Sooner Than We Had Thoug...
MacRumors, cites KGI securities analyst Ming Chi Kuo, well-respected as an Apple product prognisticator, saying that Apple will introduce an upgraded iPad Air and iPad mini in 2014/Q3, meaning the... Read more
Toshiba Unveils New High And Low End Laptop M...
Toshiba has announced new laptop models covering both the high-end and low-end of the notebook computer spectrum. Toshiba 4K Ultra HD Laptop Toshiba’s new Satellite P55t features one of the world’s... Read more
Save up to $270 with Apple refurbished 13-inc...
The Apple Store has Apple Certified Refurbished October 2013 13″ Retina MacBook Pros available starting at $1099, with models up to $270 off MSRP. Apple’s one-year warranty is standard, and shipping... Read more
Apple now offering refurbished iPad mini with...
The Apple Store has Certified Refurbished 2nd generation iPad minis with Retina Displays now available starting at $339. Apple’s one-year warranty is included with each model, and shipping is free.... Read more
Microsoft Blinks – Drops Microsoft Office 365...
Microsoft has dropped the annual subscription fee for Microsoft Office 365 Personal – which is needed in order to create and edit documents in Microsoft Office for iPad. However, Apple’s iOS and OS X... Read more
New AVG Vault Apps for iOS and Android Help K...
AVG Technologies N.V. an online security company for 177 million active users, has announced the launch of its latest mobile application, AVG Vault. The free app introduces an innovative user... Read more

Jobs Board

*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Retail - Manager - Holyoke - Apple I...
Job Summary Keeping an Apple Store thriving requires a diverse set of leadership skills, and as a Manager, you’re a master of them all. In the store’s fast-paced, Read more
*Apple* Retail - Manager - Apple (United Sta...
Job SummaryKeeping an Apple Store thriving requires a diverse set of leadership skills, and as a Manager, you're a master of them all. In the store's fast-paced, dynamic Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Retail - Market Leader - Cincinnati...
…challenges of developing individuals, building teams, and affecting growth across Apple Stores. You demonstrate successful leadership ability - focusing on excellence Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.