C-sample Hardware Issues and Change Requests

[Lenti84]

I'm planning to design an updated version of the hardware. Next step of hardware will be called C-sample.
Therefore i want to collect known issues and possible change requests.

currently known issues

• B4: footprint for dc-dc converter: crossed secondary side pinout for gnd and vout
• V3: false assembly of NPN bipolar instead of PNP type
• X15, 21: hole diameter to small
• X1...X12: connection to MEBP_4-4S wrong: interchange pin 1 with pin 2
• no holes for case screws

change requests

• current consumption of L293 is 50 mA each, should be lowered, maybe U1, U3, U8 should be shut down during idle
• voltage devider at net "Sense" to match voltage levels better from opamp to STM32
• bypass capacitor for ESP8266
• replace relay K1 by analog switch
• support STM32F401 blackpill boards instead of STM32F103 bluepill
• maybe switch from ESP8266 to ESP32 or WT32-ETH01
• ....

Please feel free to comment your suggestions so maybe i can consider implementing them.

[nstadigs]

Hi! Thanks for this great project!

I have 13 valves to control. Would it be possible to squeeze in control for an extra connector (or two, to make the number even)? Or maybe add support for an extension board? 😬
I know this might be a big request, but I had to ask :)

[xal88]

Great to see some updates :-)
What I would like to have is an option to enter calibration values for the Onewire temperature sensors.
My temperature range is 15-32 deg Celsius ( cooling/heating )
If I have a bunch of DS18B20, I can see values +/- 1,5K. No need to meet the exact temparature, but all sensors should have the same base temperature, even when a little bit wrong.
Simple linear regression formula ( y= kx+d) with a way to enter the k,d values per sensor would help - otherwise I would do that in the MQTT server.
Gold star solution to have an auto-calibration mode. Run once when the whole system is OFF and its cold ( e.g. 15°C), store the values), same when distribution cabinet is hot ( 35°, and all OFF for a while ). Then do the mean values and calc the regresssion.
Cheers Alf

[Lenti84]

c-sample revision of hardware implemented --> closed