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Serial 7-Segment Display Update for Arduino 1.6.9?

 by Mike, K8LH ¦  Sun May 29, 2016 5:02 am ¦  Forum: SparkFun Product Questions ¦  Topic: Serial 7-Segment Display Update for Arduino 1.6.9? ¦  Replies: 0 ¦  Views: 464

Is there a Serial 7-Segment Display project update that compiles without warnings in Arduino 1.6.9, please? TIA... Cheerful regards, Mike Display\Serial_7_Segment_Display_Firmware\System_Functions.ino:368:32: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings] Display\Se...

Re: High Power Shift Register Shield for the Arduino Pro

 by Mike, K8LH ¦  Mon Jun 14, 2010 5:58 am ¦  Forum: SparkFun Product Questions ¦  Topic: High Power Shift Register Shield for the Arduino Pro ¦  Replies: 6 ¦  Views: 2988

Hi Lex,

Very nice looking board.

Have you looked at the Allegro A6841 or the Micrel MIC5841? Both have similar specs' to the TPIC6A595 but they have the transient suppression diodes built-in.

Cheerful regards, Mike

Re: 7 Segment LED, 74HC595, and Arduino

 by Mike, K8LH ¦  Thu Apr 29, 2010 5:27 pm ¦  Forum: SparkFun Product Questions ¦  Topic: 7 Segment LED, 74HC595, and Arduino ¦  Replies: 14 ¦  Views: 4948


Congrats! Nice video too. The only thing missing is the coffee cup ring stain on your notepad (grin)...

Kind regards, Mike

 by Mike, K8LH ¦  Sat Jan 23, 2010 10:25 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Multiplexing two 7-segment digits with only 1 pin ¦  Replies: 28 ¦  Views: 6149

Some interesting results when you can take advantage of both hardware and software though.


 by Mike, K8LH ¦  Tue Jan 12, 2010 7:01 pm ¦  Forum: SparkFun Product Questions ¦  Topic: 13x19 LED Matrix ¦  Replies: 16 ¦  Views: 8368

I agree with Senior'. As an example you could take a simple design like that below and physically place the LEDs into a 14x20 matrix which is just a bit bigger than yours. You'll have a 14% (1/7th) duty cycle which reduces "peak" current requirements and improves "average" current and brightness (yo...

 by Mike, K8LH ¦  Tue Sep 29, 2009 11:16 am ¦  Forum: SparkFun Product Questions ¦  Topic: Constant Current Driver question ¦  Replies: 17 ¦  Views: 4029


Just wondering if you're using one constant current sinking driver IC per 7-segment display or if you're multiplexing them?

Kind regards, Mike

 by Mike, K8LH ¦  Mon Sep 28, 2009 8:34 am ¦  Forum: SparkFun Product Questions ¦  Topic: Constant Current Driver question ¦  Replies: 17 ¦  Views: 4029

Have you considered connecting all of the OE pins on the driver ICs together and driving them from the PIC PWM output? Brightness will be inversely proportional to PWM duty cycle but it works with the sinking driver ICs that I use in multiplexed displays.

Good luck on you project.

Regards, Mike

 by Mike, K8LH ¦  Mon Jul 06, 2009 2:22 pm ¦  Forum: SparkFun Product Questions ¦  Topic: LED Array current source ICs ¦  Replies: 7 ¦  Views: 3214

The problem with 300ma or 500ma source driver ICs is that they don't provide the 'peak' current required to drive a row of 64 or more LEDs which are each looking for about 100ma 'peak' current (at 1/8th or 12.5% duty cycle). Use discrete 5-10 amp logic level low Rds(on) P-FET row source drivers. One...

 by Mike, K8LH ¦  Mon Jul 06, 2009 1:21 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Servo Control ¦  Replies: 5 ¦  Views: 1081

You might read up on CCP module "special event trigger" mode and consider using a small interrupt service routine to control up to 8 servos as a background task. Just modify Servo[] array values in Main with pulse width values ranging from 600 to 2400 (usecs) and ISR does the rest. Example ISR drive...

 by Mike, K8LH ¦  Thu Jul 02, 2009 6:26 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Hyperterminal non scrolling console ¦  Replies: 4 ¦  Views: 2820

Other useful ANSI control strings you may need are; "\x1B[yy;xxf" // move cursor to yy(00..23),xx(00..79) "\x1B[A" // move cursor up "\x1B[B" // move cursor down "\x1B[C" // move cursor left "\x1B[D" // move cursor right You need to replace the 'yy' and 'xx' with ascii characters in the range of '00...

 by Mike, K8LH ¦  Wed Jul 01, 2009 3:48 am ¦  Forum: SparkFun Product Questions ¦  Topic: Pushbutton Panel Mount Plunger? ¦  Replies: 3 ¦  Views: 1057

bkiba wrote:thanks that was very helpful - found some waterproof ones on mouser.
How about sharing (product link)?

Regards, Mike

 by Mike, K8LH ¦  Sun Jun 07, 2009 6:17 am ¦  Forum: SparkFun Product Questions ¦  Topic: LED scrolling marquee sign with Dot Matrix, newby here :( ¦  Replies: 155 ¦  Views: 49782


You realize that lighting one of sixty four LEDs at a time results in a 1/64th or 1.5625% duty cycle?


 by Mike, K8LH ¦  Sun Jun 07, 2009 6:09 am ¦  Forum: SparkFun Product Questions ¦  Topic: LED scrolling marquee sign with Dot Matrix, newby here :( ¦  Replies: 155 ¦  Views: 49782

davos1, That should work fine except that at a 1/8th or 12.5% duty cycle the '595 outputs (without driver transistors) will limit 'peak' and 'average' current and display brightness. If 10 to 20 ma per LED provides full brightness at a 100% duty cycle then we need approximately 8 times that amount o...

 by Mike, K8LH ¦  Fri May 29, 2009 3:34 pm ¦  Forum: SparkFun Product Questions ¦  Topic: 16x16 LED matrix ¦  Replies: 5 ¦  Views: 3324

n1ist wrote:My design at is a 16x16 matrix with 7 bits of intensity per dot (8 if you don't mind a bit of flicker)
You got a schematic for that in something other than ExpressPCB format by any chance, please?


 by Mike, K8LH ¦  Fri Feb 27, 2009 5:00 am ¦  Forum: SparkFun Product Questions ¦  Topic: First Project - LED-based BCD clock ¦  Replies: 75 ¦  Views: 14705

Image Deleted Please limit your images to 600 pixels width (or smaller) - larger PIX distort the forum pages for many of us. I apologize. Some Forums (ie.; Sourceboost, Instructables, etc.) automatically resize graphics to fit your broswer width. That feature (and others) seems to be missing in thi...