Recently Medelec35 recommended to me Matrix's BL0162 Servo Board. Details can be found here https://www.matrixtsl.com/eblocks/
Don't be put off by the name as I initially was (I had no need for controlling servos), it is in my opinion better called a "powered interface board". Plugged into an upstream board it brings out all pins of a Port to easily accessed header pins.
As well as providing a pin per bit (0-7) it also provides a Ground (VSS) and +5v (VCC) per bit connection too. This makes it an ideal board to experiment with not just servo motors, but many other modules and sensors too, simplifying connections.
Like many of you I'm sure, I've aquired many "jumpers" over the years. Some were bought from reputable sources whilst others came free with modules and over time these all got mixed together. This resulted in more than once being frustrated as to why something wasn't responding only to find out the cause was a dodgy jumper.
I decided to do something about this, testing and eliminating any that were found to be unreliable.
I have female to female (F2F), male to male (M2M) and male to female (M2F) in my collection.
My plan was to use the BL0162 to provide VCC that I would connect to a data pin via a jumper. With access to eight pins on a port I could test eight jumpers at a time just by using the board itself.
I would first test all my female to female jumpers (board only has header pins) discarding any that failed, then using the good jumpers I would test my male to female jumpers by using a combination of good F2F and the M2F jumpers. Similarly, using two good F2F I could test my M2M by bridging the gap between:-
VCC - F2F - Data
VCC - F2F - M2F - Data
VCC - F2F - M2M - F2F - Data
With connections made I'd agitate the jumpers to see if any connection "broke".
My chart would loop displaying what connections were made until I pressed the "test" button. It would then use this initial value as a reference to what should be connected.
If for example I connected four jumpers to D0 - D3 (and all was good) I'd see 0000 1111 on my display to signify connections.
When I push "test" the program loops until "test" is pushed again, which resets.
In the loop I sample the port. If all is good I should read the same value (0000 1111) as I agitate the jumpers. If any connection should fail, say D2, I would read 0000 1011 and display FAIL. To eliminate any intermittant failures, if any connection should fail whilst I'm testing, the reference value is updated to exclude this pin in future itterations.
My display would initially show 0000 1111 then when I press test it would display this reference with "samples" above.
0000 1111 <--this is the sampled value
^^^^ ^^^^
0000 1111 <--this is the reference
If D2 connection failed at any time, even intermittently, the display would then read the following and stay that way until either further failures occured or I reset.
0000 1011
^^^^ ^^^^
0000 1111
FAIL
I can see straight away that the connection on Pin D2 is suspect. If D1 subsequently failed I'd then get
0000 1001
^^^^ ^^^^
0000 1111
FAIL
My chart is far from eloquent and was quickly thrown together, which is a great feature of Flowcode. You can just quickly do stuff
As FC is chip independent you can very easily port this to any device you may have. If I had one of those ESP's with integrated display, I may even just have used that, setting for example pins on a port high, connecting them to another port and reading. However as the purpose is to test my jumpers, using anything other than "good" headers may not be a great idea....In my tests I found many dodgy jumpers and these were unsurprisingly obtained from "cheap" sources or even free (based on the build quality). I accept that I may be discarding some good jumpers too, but those found to be suspect were tested again on different ports and / or different intermediate leads to help eliminate that possibility.
You can simulate the chart and make connections using the switch array to play.
If I cared more I'd maybe tidy it up a bit and possibly eliminate the "test" button completely, maybe even just using LEDs but as I had the boards handy and they just easily plug together why create more work
- 100_0251.JPG (155.26 KiB) Viewed 1358 times
- 100_0252.JPG (122.94 KiB) Viewed 1358 times
- 100_0253.JPG (120.91 KiB) Viewed 1358 times
- 100_0255.JPG (116.02 KiB) Viewed 1358 times
What better way to waste a Sunday?
Regards
Edit......
Forgot to attatch chart, think this is the right one
thanks for sharing.