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Nimue

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Joined: 06/08/2020
Location: United Kingdom
Posts: 420

Posted: 09:12pm 10 Aug 2020

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Good morning / evening -- depending on which side of the water you are on.

Firstly, I am in love with CMM2. There, I said it.

Secondly, as a teacher adviser in Wales, the CMM2 is ideally placed to play a big role in our new curriculum -- so I blogged about it:

https://stem.wales/roll-your-own-data-logger-with-maximite-2.html

Finally, for that blog, I built and coded a simple data logger in less than 1 hour. The code is below. MMBasic gurus -- any tweaks? What I'd really like is a "speedo" type dial, but am unsure where to start.....

' Basic light meter functionality - not calibrated

CLS

open "light.txt" for output as #1 ' Defaults to opening from SD Card

close #1 ' Open / Close to make sure the file exists - quick and dirty

SETPIN 7,AIN 'Uses pin number 7 for Analogue Input (AIN)

Do

open "light.txt" for append as #1

light = Pin(7) ' reads pin 7

box 0,0,400,20,2,,rgb(black) ' draws a light meter scale
box 0,0,light*100,20,2,,rgb(red) ' displays the current value

teXT 450,5, format$(light*1000,"%0.0f"), "R" 'prints the current value

print #1,TIME$, format$(light*1000,"%0.0f") 'outputs to file the time and light value

text_log$="Logged at " + Time$ ' on screen output

text 550,5, text_log$

close #1 ' as we pause for 1 min, close file in case of crash

pause 60000 ' Wait 1 minute or 60000 miliseconds

Loop while INKEY$<>chr$(27) ' Exit if ESC is pressed
cls ' keeps screen tidy on exit

Entropy is not what it used to be

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6283

Posted: 09:23pm 10 Aug 2020

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Hi and welcome.
(I have a sister in Wales. She was planning to come and visit in April but Covid put a stop to those plans!)

I would use a SETTICK interrupt instead of the PAUSE 60000
That allows you to do all sorts of other things while you wait. Draw a chart of the light over time perhaps.

' Basic light meter functionality - not calibrated
CLS
OPEN "light.txt" FOR output AS #1 ' Defaults to opening from SD Card
CLOSE #1 ' Open / Close to make sure the file exists - quick and dirty
SETPIN 7,AIN 'Uses pin number 7 for Analogue Input (AIN)

SETTICK 60000, myLight ' run myLight sub every 60 seconds

DO
' do other things while you wait

LOOP WHILE INKEY$<>CHR$(27) ' Exit if ESC is pressed
CLS ' keeps screen tidy on exit
END

SUB myLight
OPEN "light.txt" FOR append AS #1
light = PIN(7) ' reads pin 7
BOX 0,0,400,20,2,,RGB(BLACK) ' draws a light meter scale
BOX 0,0,light*100,20,2,,RGB(RED) ' displays the current value
TEXT 450,5, format$(light*1000,"%0.0f"), "R" 'prints the current value
PRINT #1,TIME$, format$(light*1000,"%0.0f") 'outputs to file the time and light value
text_log$="Logged at " + TIME$ ' on screen output
TEXT 550,5, text_log$
CLOSE #1 ' as we pause for 1 min, close file in case of crash
END SUB

Jim

VK7JH
MMedit

JohnS
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Joined: 18/11/2011
Location: United Kingdom
Posts: 4044

Posted: 09:28pm 10 Aug 2020

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Love it!

typo on the web page - just under the heading "The potential of creating your own logger", there's a left paren matched with a right bracket (aka square bracket).

John

Nimue

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Joined: 06/08/2020
Location: United Kingdom
Posts: 420

Posted: 09:33pm 10 Aug 2020

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JohnS said Love it!

typo on the web page - just under the heading "The potential of creating your own logger", there's a left paren matched with a right bracket (aka square bracket).

John

Cheers - good eyes -- fixed.

Nim

Entropy is not what it used to be

Sasquatch

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Joined: 08/05/2020
Location: United States
Posts: 377

Posted: 09:35pm 10 Aug 2020

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Check out the latest version of "Lunar Lander" in this thread:

https://www.thebackshed.com/forum/ViewTopic.php?TID=12303&PID=152030#152030#152030

Andrew has done some very nice circular "speedo" type gauges.

-Carl

Nimue

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Joined: 06/08/2020
Location: United Kingdom
Posts: 420

Posted: 09:35pm 10 Aug 2020

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TassyJim said Hi and welcome.
(I have a sister in Wales. She was planning to come and visit in April but Covid put a stop to those plans!)

I would use a SETTICK interrupt instead of the PAUSE 60000
That allows you to do all sorts of other things while you wait. Draw a chart of the light over time perhaps.

Jim

I'm in the Cardiff area -- very urban - not the pretty part unfortunatley.

Love the SETTICK feedback -- one to investigate for version II.

Cheers

Nim

Entropy is not what it used to be

Nimue

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Joined: 06/08/2020
Location: United Kingdom
Posts: 420

Posted: 09:36pm 10 Aug 2020

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Sasquatch said Check out the latest version of "Lunar Lander" in this thread:

https://www.thebackshed.com/forum/ViewTopic.php?TID=12303&PID=152030#152030#152030

Andrew has done some very nice circular "speedo" type gauges.

Perfect - code "borrowed".....

Nim

Entropy is not what it used to be

CaptainBoing

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Joined: 07/09/2016
Location: United Kingdom
Posts: 2170

Posted: 08:04am 11 Aug 2020

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back in 1984, I did two modules for a teacher friend. They used something called a "VELA"(?)

He wanted an adaptor to shine a tungsten bulb through an inserted test tube them measure the light from it in RGB. It was a cow trimming to get even near a flat response. Got hold of some very good filters but we were fighting the emissions of the tungsten - strong in the red and tails of to hardly anything in the blue. Then the response of the ORP12s... But it was good enough in the end.

Nimue

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Joined: 06/08/2020
Location: United Kingdom
Posts: 420

Posted: 08:46am 11 Aug 2020

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CaptainBoing said back in 1984, I did two modules for a teacher friend. They used something called a "VELA"(?)

He wanted an adaptor to shine a tungsten bulb through an inserted test tube them measure the light from it in RGB. It was a cow trimming to get even near a flat response. Got hold of some very good filters but we were fighting the emissions of the tungsten - strong in the red and tails of to hardly anything in the blue. Then the response of the ORP12s... But it was good enough in the end.

VELA / Data Harvest are the "big boys" in education data loggers -- expensive and slick and Iirc you are wedded to their sensors.

FWIW: https://www.retro-kit.co.uk/VELA/

Another "roll your own" project is to make a colorimiter -- white LED emitter shining through a small cuvette and an LDR sensor --> to measure how much light passes through. Basic high school stuff but the colorimiters cost �200+ and are black box again.

I think I'll 3D print some kit and this will be my next project.

Nim

Entropy is not what it used to be

Andrew_G
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Joined: 18/10/2016
Location: Australia
Posts: 871

Posted: 10:53pm 11 Aug 2020

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Hi Nim,
Welcome. I'm sure you will get a lot of support from Shedders for helping your young people to learn and explore.
The "gauges" in Lunar Lander are intentionally pretty basic (no pun).
Here are is a much better one. In that thread I raised a couple of issues with the ARC statement. One is that you can't apply an aspect ratio (like you can in CIRCLE). I have experimented with Panky's code above and you can multiply his SIN components by your aspect ratio and get a circle on your monitor. I abandoned it because in LL the non-circle looks better and it was getting more complex than I wanted.
If you read the manual for "MM+" ie Micromite Plus there are several standard gauges that are not (yet) part of the CMM2.

Keep up the good work,

Andrew

{Edit: I'd meant to say how much I love Wales - I spent 3 years in Manchester in the mid-seventies and Wales was a day trip for us Aussies}
Edited 2020-08-12 08:57 by Andrew_G

Nimue

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Joined: 06/08/2020
Location: United Kingdom
Posts: 420

Posted: 08:46am 12 Aug 2020

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Andrew - good morning (for me).

Wales is beautiful -- sadly I live in the urban areas near Cardiff. That said, the beautiful parts are a 30minute drive away. A "day trip" for me is "Barrybados" (Google it

).

Manchester / Liverpool - which technically a day trip would be seen as a "big drive" for us!!

Thanks for the heads up -- will check your post and the MM+ manual.

Have just coded up gauges using the Lander example -- quite easy in retrospect -- and certainly easy enough for beginners to understand (will be teaching to 10-14 yr olds).

Cheers
Nim

Entropy is not what it used to be

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