Recommend a 10m wire for microcontroller

[redhat]

i want to connect a number of seven segments and push-buttons to a microcontroller, the problem is that they will be far away from the microcontroller about 10m or maybe more, what type of wire could i use, so that the circuit will work probably as i am afraid of the attenuation of the signal?

regards

 

[SkyHigh]

Re: Wire Length to mcu

It's not about wire. It's about using the appropriate protocol to overcome the problems of transmission line effects over lengths such as 10m or longer. Another issue is high power consumption in driving signals over a long wire.

A common technique you can use is Low-Voltage Differential Signalling (LVDS), but I recommend you to use Wireless protocols such as Bluetooth and Zigbee that are cheap and simple to use. It is also low-power and wire maintenance-free.

Another option is to use FM/AM/FSK technique such as 433MHz FM transceiver, which comes in some microcontrollers such as ones in Microchip PIC16 and PIC18 series.

If you seriously insist on using 10m long wire, the problem is where are you going to place a repeater to boost your signals? You might even end up building a bus, implementing CAN, I2C, USB, Ethernet and etc that incur overhead costs.

 

[IanP]

Re: Wire Length to mcu

10m is not the end of the Earth ..
To 7-segment display use transistor buffers (can be transistor arrays such as ULN2003 or similar) and you can use multicore shielded data cable with conductor gauge >28AWG .. after all we are talking about mAs ..
As for inputs from buttons, use separate shielded multicore cable (the same data cable with >28AWG), use Schmitt Trigger inverter such as SN74(LS, HC)14 or CD4093 as buffers, and connect 10nF capacitor with 5.1V zener diode between inputs and 0V, and 1kΩ as pull-up ..
In this situation a button will operate between this input and 0V ..
... and everything should be OK ..
Regards,
IanP