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viscomjim
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Joined: 08/01/2014
Location: United States
Posts: 925

Posted: 12:31pm 07 Jul 2014

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Trying to do a countdown timer in which I have to separate the individual digits from thousands, hundreds, tens and ones (counting from 1 to 9999). This method works, but is there a better way that anyone has come across???

Z = 0
FOR Z = 0 TO 9999
THOU = INT(Z/1000)
HUND = INT((Z-(THOU * 1000))/100)
TENS = INT((Z-((THOU * 1000) + (HUND * 100)))/10)
ONES = Z - ((THOU * 1000) + (HUND * 100) + (TENS * 10))
'DO SOME STUFF
NEXT Z

I hope I won't be too embarrassed with the answers.

Thanks again!!!

BobD

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Joined: 07/12/2011
Location: Australia
Posts: 935

Posted: 12:39pm 07 Jul 2014

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Jim
MMBasic has an integer divide implemented by a backslash \
Careful use of it could save a bit of time and code.

THOU = Z\1000
etc.

apart from that I have no suggestions
Bob

atmega8

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Joined: 19/11/2013
Location: Germany
Posts: 723

Posted: 12:51pm 07 Jul 2014

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Nice thing,

Could not find any documentation on ebay?!

viscomjim
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Joined: 08/01/2014
Location: United States
Posts: 925

Posted: 01:05pm 07 Jul 2014

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EBAY???

Gizmo

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Joined: 05/06/2004
Location: Australia
Posts: 5111

Posted: 01:05pm 07 Jul 2014

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Convert it to a string and use mid$ ?

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

Geoffg

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Joined: 06/06/2011
Location: Australia
Posts: 3269

Posted: 01:57pm 07 Jul 2014

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MOD would also come in handy, for example:

ONES = Z MOD 10

Geoff Graham - http://geoffg.net

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6220

Posted: 02:02pm 07 Jul 2014

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This a string version.

I am not sure which method will be the fastest or most memory conservative.

DO
INPUT x
xstring$=RIGHT$("000"+STR$(x),4) ' this should work for all versions of MMBasic
units=VAL(MID$(xstring$,4,1))
tens=VAL(MID$(xstring$,3,1))
hundreds=VAL(MID$(xstring$,2,1))
thousands=VAL(MID$(xstring$,1,1))
PRINT thousands,hundreds,tens,units
LOOP UNTIL x = -1
END

Jim

VK7JH
MMedit

viscomjim
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Joined: 08/01/2014
Location: United States
Posts: 925

Posted: 02:43pm 07 Jul 2014

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Quick time test using numbers and strings...

test method courtesy of Peter G8JCF - this is running on a uMite 28 at 48mhz...

L=TIMER
FOR Z= 1 TO 9999
THOU = z\1000
HUND = ((Z-(THOU * 1000))\100)
TENS = ((Z-((THOU * 1000) + (HUND * 100)))\10)
ONES = Z - ((THOU * 1000) + (HUND * 100) + (TENS * 10))
NEXT Z
PRINT "Method 1 "; TIMER-L

L=TIMER
FOR Z= 1 TO 9999
xstring$=RIGHT$("000"+STR$(x),4) ' this should work for all versions of MMBasic
units=VAL(MID$(xstring$,4,1))
tens=VAL(MID$(xstring$,3,1))
hundreds=VAL(MID$(xstring$,2,1))
thousands=VAL(MID$(xstring$,1,1))
NEXT Z
PRINT "Method 2 "; TIMER-L

results...

Method 1 7090
Method 2 11544

I'm going to have to try the MOD method next...

Edited by viscomjim 2014-07-09

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6220

Posted: 05:15pm 07 Jul 2014

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L=TIMER
FOR Z= 1 TO 9999
THOU = z\1000
HUND = ((Z-(THOU * 1000))\100)
TENS = ((Z-((THOU * 1000) + (HUND * 100)))\10)
ONES = Z - ((THOU * 1000) + (HUND * 100) + (TENS * 10))
'PRINT thou,hund,tens,ones
NEXT Z
PRINT "Method 1 "; TIMER-L

L=TIMER
FOR Z= 1 TO 9999
xstring$=RIGHT$("000"+STR$(x),4) ' this should work for all versions of MMBasic
units=VAL(MID$(xstring$,4,1))
tens=VAL(MID$(xstring$,3,1))
hundreds=VAL(MID$(xstring$,2,1))
thousands=VAL(MID$(xstring$,1,1))
'
NEXT Z
PRINT "Method 2 "; TIMER-L

L=TIMER
FOR Z= 1 TO 9999
THOU = z\1000
HUND = (Z MOD 1000)\100
TENS = (Z MOD 100)\10
ONES = Z MOD 10
'PRINT thou,hund,tens,ones
NEXT Z
PRINT "Method 3 "; TIMER-L

Results (uMite at 40MHz):
[13:12:37]Method 1 8320
[13:12:50]Method 2 13376
[13:12:55]Method 3 5248

Using MOD is a big improvement!

JimEdited by TassyJim 2014-07-09

VK7JH
MMedit

viscomjim
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Joined: 08/01/2014
Location: United States
Posts: 925

Posted: 05:38pm 07 Jul 2014

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Hell yeah TassyJim...

Method 1 6978
Method 2 11271
Method 3 4456

uMite at 48mhz

That absolutely rocks!!!!!

This will allow for an easy 100th of a second accuracy on a timer with display update, etc... Very Cool.

Here is my code for quick timer with 100th of a second display on adafruit i2c led display.

DIM T(10)
T(0)=&H3F:T(1)=&H06:T(2)=&H5B:T(3)=&H4F:T(4)=&H66
T(5)=&H6D:T(6)=&H7D:T(7)=&H07:T(8)=&H7F:T(9)=&H6F
I2C OPEN 400,100
I2C WRITE &H70, 0, 1, &H21
I2C WRITE &H70, 0, 1, &H81
I2C WRITE &H70, 0, 1, &HEF
Z=0
SETTICK 10, UPDATE, 1
TM=TIMER
DO:LOOP
UPDATE:
Z = Z + 1
THOU = z\1000
HUND = (Z MOD 1000)\100
TENS = (Z MOD 100)\10
ONES = Z MOD 10
I2C WRITE &H70, 0, 2, &H00, T(THOU)
I2C WRITE &H70, 0, 2, &H02, T(HUND)
I2C WRITE &H70, 0, 2, &H06, T(TENS)
I2C WRITE &H70, 0, 2, &H08, T(ONES)
IF Z = 9999 THEN
TM=TIMER-TM
PRINT "Z = ";Z;" TIMER = ";TM
TM=TIMER
Z=0
ENDIF
IRETURN

Edited by viscomjim 2014-07-09

halldave

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Joined: 04/05/2014
Location: Australia
Posts: 121

Posted: 09:31pm 07 Jul 2014

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would this code work for MAX7219 8-Bit Red LED Tube Display Module??

regards

David

viscomjim
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Joined: 08/01/2014
Location: United States
Posts: 925

Posted: 12:54am 08 Jul 2014

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Hi David,

The max7219 has an spi interface, which the uMite can do. I am experimenting with the 8 digit tube display and the 8x8 matrix that uses that chip and will report back soon (i hope) with code for those.

Forum member Boss has written code for the tube display for Maximite here.

A few changes are required for uMite as it has dedicated pins for spi interface and Maximite can use just about any pins for that. Still playing and will keep you posted.Edited by viscomjim 2014-07-09

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