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5 x URM37 but FEZ Panda II have only COM1, COM2, COM3, COM4


#1

Hello,
Sorry for my english.

I have 5 x URM37 (http://www.dfrobot.com/wiki/index.php/URM37_V3.2_Ultrasonic_Sensor_(SKU:SEN0001)), but fez panda have only 4 x COM port. How can i resolve it?
Thanks everyone.


#2

Is there a better solution?


#3

Use 4 sensors ?
Use two Pandas?

You only have 4 UARTs, and you have 5 devices needing UARTs. I don’t think you’ll find a software UART or could write one. At the minimum, assuming you can get to all UARTs on your Panda II (I haven’t checked), if you just buy one replacement sensor you’ll get by.


#4

SN74LV4052A


#5

Bill, Bill, Bill, bill, Bill… that’ll multiplex the lines, yes, but that’s not going to really help you get good sentences from the devices… Could be quite a challenge to orchestrate, and may work, but I wouldn’t want to take that on.


#6

yeah it will fella - cycle thru each senser - request the distance, move onto the next one
Bob’s your uncle, fannies your aunt - Job done :slight_smile:


#7

Try this Serial Port Mux board. It requires 1 Rx/TX input and can handle 4 separate serial devices.

https://www.atlas-scientific.com/product_pages/embedded/serial-port-connector.html


#8

I had a look at the sensors data sheet and yes since they aren’t spewing out data like a GPS, it looks to be more an ask + response transaction, that will work (although I can still sense some challenges to code into it, serial port timeouts for example). If there’s any chance the data will appear on the serial port without interaction (say an alarm capability when you hit a specific distance) then it would not reliably get that data