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Electronics => Beginners => Topic started by: Silenus on January 13, 2015, 02:53:46 am

Title: RTS and CTS UART pins
Post by: Silenus on January 13, 2015, 02:53:46 am
Hey guys, I am looking to put a WiFly (http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Wireless/WiFi/WiFly-RN-171-DS.pdf) into an embedded board that I'm making. In the datasheet, it says the most basic setup uses the PWR RX TX GND, however in the diagrams the UART is utilising the additional CTS and RTS pins. Do I need to connect these pins for serial comms to work between the module and MCU?
Title: Re: RTS and CTS UART pins
Post by: apelly on January 13, 2015, 03:09:15 am
RTS & CTS are for hardware handshaking. With only RX, TX & GND you can do software, XON/XOFF handshaking.

I haven't looked but you'll probably find that the WiFly is configurable for either. I don't think much uses hardware handshaking anymore, but I am prepared to be corrected.
Title: Re: RTS and CTS UART pins
Post by: digsys on January 13, 2015, 03:37:33 am
agreed. Worst case, you tie RTS or CTS High (whichever is designated as Input to the WiFi module). ie always on.