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Forum Index : Microcontroller and PC projects : MMbasic "time"
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lew247 Guru  Joined: 23/12/2015 Location: United KingdomPosts: 1676 |
Is there an easy way to get a 1 second pulse output at the start of every second after setting the internal clock? I've been reading the manual and found TIME$ = "HH:MM:SS" or TIME$ = "HH:MM" or TIME$ = "HH" Sets the time of the internal clock. MM and SS are optional and will default to zero if not specified. For example TIME$ = "14:30" will set the clock to 14:30 with zero seconds. The time is set to "00:00:00" on power up. but it doesn't say what you can do with the time once its set? I'm still trying to get my head round basic, I learnt it first when I was 16 in 1977 on a computer at college which had 4k ram, basic was programmed into it by punchcard and we typed the programs in manually, and there was only a printer output with no monitor back then. Its hard remembering some of the commands, and there are a good few new ones to learn |
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| matherp Guru Joined: 11/12/2012 Location: United KingdomPosts: 8591 |
here is how I would do it Const pulsepin=21 'assign the pin you want the pulse on
Const width=50 'set the pulse time in msec SetPin pulsepin,dout 'set the chosen pin as an output pin(pulsepin)=0 'set whether the pin should rest low or high SetTick 1000,pulseout 'setup a 1 second interrupt Do 'wait forever, the pulses will happen in the background Loop ' Sub pulseout 'called every second Pulse pulsepin,width 'fire off a pulse for "width" msec End Sub |
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atmega8 Guru Joined: 19/11/2013 Location: GermanyPosts: 712 |
Wow, what a service. A complete "Program" from Peter 
The thing that makes it is the Timer "SetTick 1000,pulseout". Have a look at the manual, it is easy to understand: ************************************************************************************ A timing function is also provided by the SETTICK command. This command will generate an interrupt at regular intervals (specified in milliseconds). Think of it as the regular "tick" of a watch. For example, the following code fragment will print the current time and the voltage on pin 2 every second. This process will run independently of the main program which could be doing something completely unrelated. SETPIN 2, AIN SETTICK 1000, DOINT DO ‘ main processing loop LOOP SUB DOINT ‘ tick interrupt PRINT TIME$, PIN(2) END SUB The second line sets up the "tick" interrupt, the first parameter of SETTICK is the period of the interrupt (1000 mS) and the second is the starting label of the interrupt code. Every second (ie, 1000 mS) the main processing loop will be interrupted and the program starting at the label DOINT will be executed. ************************************************************************************ |
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| lew247 Guru Joined: 23/12/2015 Location: United KingdomPosts: 1676 |
Thank you so much |
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| Bizzie Senior Member  Joined: 06/07/2014 Location: AustraliaPosts: 185 |
Further to the excellent explanations above. Is there any way to synchronize the SETTICK to the start of the minute or hour? Rob White |
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OA47 Guru Joined: 11/04/2012 Location: AustraliaPosts: 903 |
I would suppose that the clock and settick are derived from the same signal so if for example your settick arrived 23 seconds behind the start of the hour you could add that difference in your code? GM |
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| mindrobots Newbie  Joined: 21/05/2014 Location: United StatesPosts: 32 |
What if you set the time to something ending in :00 and the immediately after that do the SETTICK with the interval you want? By setting the time at :00 you've established the "zero seconds" point and synched the internal RTC. Every tick interval after that should be pretty accurate for the interval you set. I would think this would be accurate enough for most events. You could tune it a bit for drift if needed. Or like said above, if it is 10:51:00 when you initially set the time then just set the initial SETTICK interval for 9 minutes. The interrupt routine would then always set the interval for 60 minutes (less however long it runs) to have another pulse at the top of the next hour. |
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TassyJim Guru Joined: 07/08/2011 Location: AustraliaPosts: 5907 |
You can keep testing the time until the seconds (or minutes and seconds) are zero. You may need to put a flag in to stop the code running more than once. You set the flag once triggered and then later in your code when the trigger value is past, reset the flag ready for next time. triggered = 0 ' we only want to run the code once
main: DO test$ = TIME$ LOOP UNTIL MID$(test$,7,2)="00" AND triggered = 0 triggered = 1 PRINT test$ GOTO main The micromites that don't use a crystal and don't have very good timekeeping without fine tuning. Jim VK7JH MMedit  MMBasic Help |
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| ajkw Senior Member Joined: 29/06/2011 Location: AustraliaPosts: 290 |
In response to Bizzie, perhaps this would do Dim ss$ As string SetTick 1000,sync,1 Print Time$ Do Loop Sub sync ss$ = Mid$(Time$,7,2) Print "."; If ss$ = "00" Then SetTick 10000,pulsemin,2 '10000 for 10sec, 60000 for 1 minute SetTick 0,sync,1 'turn of sync Print "sync@";Time$ EndIf End Sub Sub pulsemin Print Time$ End Sub Anthony. Use code as your own risk & always test for your own suitability. |
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| atmega8 Guru Joined: 19/11/2013 Location: GermanyPosts: 712 |
.....and sometimes comes the time, where you reach the point, to use one of the cheap, precise and fully Micromite supported RTC's...... |
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