# hardware flowcontrol (rts/cts)!!!!

**URL:** <https://forums.digi.com/t/hardware-flowcontrol-rts-cts/3707>\
**Category:** Plug N' Play\
**Tags:** rts-cts\
**Created:** [February 28, 2008, 3:39pm UTC](https://forums.digi.com/t/hardware-flowcontrol-rts-cts/3707 "2008-02-28T15:39:26Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![User317](https://avatars.discourse-cdn.com/v4/letter/u/e0b2c6/32.png) [@User317](https://forums.digi.com/u/User317)\
**Post date:** [February 28, 2008, 3:39pm UTC](https://forums.digi.com/t/hardware-flowcontrol-rts-cts/3707/1 "2008-02-28T15:39:26Z")

</div>

Is somebody using the hardware flowcontrol (rts/cts)???

I’m able to send RCI Request over the serial interface (UART). It all works fine but just without flowcontrol! I’m sure flowcontrol is set to “hardware” and GPIO is not used (serial)!

So why has setting CTS no affect?

---

<div class="post-metadata">

**Author:** ![User317](https://avatars.discourse-cdn.com/v4/letter/u/e0b2c6/32.png) [@User317](https://forums.digi.com/u/User317)\
**Post date:** [March 5, 2008, 12:43pm UTC](https://forums.digi.com/t/hardware-flowcontrol-rts-cts/3707/2 "2008-03-05T12:43:35Z")

</div>

it seems that harware handshake (rts/cts) only works in connection mode (for example tcpconnection) and not in RCI.

---

<div class="post-metadata">

**Author:** ![KARIROW](https://avatars.discourse-cdn.com/v4/letter/k/e47774/32.png) [@KARIROW](https://forums.digi.com/u/KARIROW)\
**Post date:** [March 19, 2011, 5:16pm UTC](https://forums.digi.com/t/hardware-flowcontrol-rts-cts/3707/3 "2011-03-19T17:16:46Z")

</div>

I´ve had the same problem. It seems that digi engineers had not take it in account when testing the Realport behaviour. It´s a great problem that I had to deal with. I mean, RTS and CTS lines pass BUT HAS NO EFFECT on the other side.