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Re: Enclosure Fabrication

 by millercommamatt ¦  Sun Apr 07, 2019 1:42 pm ¦  Forum: General Chit Chat ¦  Topic: Enclosure Fabrication ¦  Replies: 5 ¦  Views: 182

From a production stand point, it sounds like you'll have at least an extrusion operation and a stamping operation. I can not imagine you'll get a job shop to touch it for only $200. Cutting your shape from solid stock would cost almost that just in material. And for extrusion prototyping, it would ...

Re: Help Hooking up a Scoreboard Display

 by millercommamatt ¦  Fri Apr 05, 2019 1:28 pm ¦  Forum: Projects ¦  Topic: Help Hooking up a Scoreboard Display ¦  Replies: 2 ¦  Views: 78

Start by thinking about how the code should work. When it comes to physical computing, think about the physical inputs. i.e. When a thing happens, what should happen as a result. e.g. When sensor A detects a score, increment display A by one. If, the new number is 7, reset all displays to zero. If y...

Re: Enclosure Fabrication

 by millercommamatt ¦  Fri Apr 05, 2019 1:18 pm ¦  Forum: General Chit Chat ¦  Topic: Enclosure Fabrication ¦  Replies: 5 ¦  Views: 182

Size? Material? Budget? Features? Already designed or do you need it designed too?

Re: Making our own Qwiic Cables? Parts List

 by millercommamatt ¦  Fri Mar 29, 2019 12:02 pm ¦  Forum: QWIIC System ¦  Topic: Making our own Qwiic Cables? Parts List ¦  Replies: 8 ¦  Views: 164

What's your application where PVC cable jackets won't work? It's a pretty good material choice for cable jackets in most situations. The situations where it is not that also intersect with hobby electronics are usually interesting to hear about. If you're going through all this trouble with cabling,...

Re: soil moisture sensor

 by millercommamatt ¦  Thu Mar 28, 2019 10:33 am ¦  Forum: Combo boards & other ¦  Topic: soil moisture sensor ¦  Replies: 1 ¦  Views: 60

ADC_out = ( V_reading / V_supply) * (2^ADC_bits - 1)

or as more typically seen

V_reading = (ADC_Reading/(2^ADC_bits - 1 )) * V_supply

Make sure the voltage you're supplying to the sensor is also the reference for your ADC.

Re: TMP36 provides discrete values and varies widely

 by millercommamatt ¦  Thu Mar 28, 2019 8:24 am ¦  Forum: Temperature & humidity ¦  Topic: TMP36 provides discrete values and varies widely ¦  Replies: 3 ¦  Views: 73

Can you post more of your code? Also, can you provide either a pictures of the connections or a schematic? Finally, can you show examples of the sensor output including the raw ADC values, your calculated voltage, and your calculated temperature? Also, the datasheet examples show the use of a decoup...

You could use an I2C multiplexer to solve your conflicting I2C address issue.

Re: Noob looking for a wiring diagram.

 by millercommamatt ¦  Tue Mar 12, 2019 5:02 pm ¦  Forum: Bluetooth ¦  Topic: Noob looking for a wiring diagram. ¦  Replies: 3 ¦  Views: 92

What microcontroller are you using? What are you doing with the WiFi and Bluetooth?

Re: SAMD21 Pro RF LoRa Sleep Current

 by millercommamatt ¦  Tue Mar 12, 2019 12:53 pm ¦  Forum: SAMD ¦  Topic: SAMD21 Pro RF LoRa Sleep Current ¦  Replies: 5 ¦  Views: 132

Are you sure you're not just measuring the burden voltage of your multimeter?

Re: Power Supply on a separate PCB

 by millercommamatt ¦  Mon Mar 11, 2019 2:14 pm ¦  Forum: PCB Design ¦  Topic: Power Supply on a separate PCB ¦  Replies: 2 ¦  Views: 77

Maybe for high voltage separation if it's powered from the mains. It might also facilitate using the board in multiple products to make it easier to conform to power standards in different countries.

Re: SF Pro RF: unreasonable current draw

 by millercommamatt ¦  Mon Mar 11, 2019 2:07 pm ¦  Forum: Power Management ¦  Topic: SF Pro RF: unreasonable current draw ¦  Replies: 2 ¦  Views: 98

Are you putting the radio to sleep with not in use? I think if you don't explicitly put it to sleep, it sits there and listens.

Are you taking advantage of the sleep/low-power functions of the microcontroller? In my experience, they don't sleep unless you tell them to.

Re: Cherry MX Breakout

 by millercommamatt ¦  Mon Mar 11, 2019 1:55 pm ¦  Forum: Miscellaneous ¦  Topic: Cherry MX Breakout ¦  Replies: 1 ¦  Views: 57

It sounds like you need a pull down resistor. Put a 10K resistor between Pin 2 and ground.

Re: led , battery, resistor... questions

 by millercommamatt ¦  Mon Mar 11, 2019 1:23 pm ¦  Forum: LEDs, Illumination, & lasers ¦  Topic: led , battery, resistor... questions ¦  Replies: 3 ¦  Views: 134

Best practice is that each LED gets its own resistor. LED forward voltages and resistor values are all variable within their tolerance bounds. If everything goes through one resistor, the LEDs will see different currents and sometimes bad things happen. A few LEDs in series with a resistor is usuall...

Re: Temprature control

 by millercommamatt ¦  Fri Mar 01, 2019 3:40 pm ¦  Forum: Projects ¦  Topic: Temprature control ¦  Replies: 3 ¦  Views: 235

I'd just buy a PID temperature controller and wire it to the heater controls.

Re: ZED-F9P shipping

 by millercommamatt ¦  Fri Mar 01, 2019 3:38 pm ¦  Forum: Global Positioning System(GPS) ¦  Topic: ZED-F9P shipping ¦  Replies: 3 ¦  Views: 167

Looking at the integration sheet, the device shouldn't need updating.