# ttyAMA0 fails with pHAT on RPi3 **URL:** \ **Category:** Raspberry Pi\ **Created:** [June 10, 2017, 5:32pm UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012 "2017-06-10T17:32:42Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![lucidman](https://avatars.discourse-cdn.com/v4/letter/l/34f0e0/32.png) [@lucidman](https://forums.pimoroni.com/u/lucidman)\ **Post date:** [June 10, 2017, 5:32pm UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012/1 "2017-06-10T17:32:42Z")
Newly installed Propeller HAT on Raspberry Pi 3 fails the following command: sudo propman Your-first-SPIN-program.binary … with the following response: pm.device: Failed to open device: "ttyAMA0" pm.device: Failed to open device: "ttyAMA0" pm.device: Failed to open device: "ttyAMA0" pm.device: Failed to open device: "ttyAMA0" pm.device: Failed to open device: "ttyAMA0" pm.loader: [ttyAMA0] EROR: DEvice not open I followed the instructions to ensure that ttyAMA0 is enabled more than once with no success. I had first performed a lengthy update to my Jessie Pi OS, then followed the instruction to install the IDE. Openspin failed at first, until I changes its owner and group to ‘pi’. But uploads to the hat always fail with the above message. Any suggestions are welcome. ---
**Author:** ![gadgetoid](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/gadgetoid/32/13_2.png) [@gadgetoid](https://forums.pimoroni.com/u/gadgetoid)\ **Post date:** [June 10, 2017, 5:53pm UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012/2 "2017-06-10T17:53:39Z")
The Pi 3 wreaks havoc on the UART setup by giving the hardware over to Bluetooth and using, iirc, a software alternative to serve the ttyAMA0 pins. This mucks with the precise timings that the Propeller chip relies upon. You need to add `dtoverlay=pi3-disable-bt` or `dtoverlay=pi3-miniuart-bt` to `/boot/config.txt` See here for details on what those do: [https://github.com/raspberrypi/firmware/blob/master/boot/overlays/README#L957-L982](https://github.com/raspberrypi/firmware/blob/master/boot/overlays/README#L957-L982) ---
**Author:** ![lucidman](https://avatars.discourse-cdn.com/v4/letter/l/34f0e0/32.png) [@lucidman](https://forums.pimoroni.com/u/lucidman)\ **Post date:** [June 10, 2017, 7:02pm UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012/3 "2017-06-10T19:02:22Z")
gadgetoid, Thanks for you quick response. I applied ‘dtoverlay=pi3-disable-bt’, rebooted, but no success. I get the same response as before. I searched for startup messages in /var/log/syslog, and found no hint of an error related the overlay change. I also applied ‘sudo systemctl disable hciuart’ before reboot per the info text. ---
**Author:** ![lucidman](https://avatars.discourse-cdn.com/v4/letter/l/34f0e0/32.png) [@lucidman](https://forums.pimoroni.com/u/lucidman)\ **Post date:** [June 10, 2017, 7:46pm UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012/4 "2017-06-10T19:46:00Z")
gadgetoid, My suspicion is that if I place ‘dtoverlay=pi3-disable-bt’ in /boot/config.txt I must also possess a file named ‘pi3-disable-bt-overlay.dtb’ in /boot/overlays. Am I right? If so, where do I get that file? ---
**Author:** ![gadgetoid](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/gadgetoid/32/13_2.png) [@gadgetoid](https://forums.pimoroni.com/u/gadgetoid)\ **Post date:** [June 10, 2017, 8:24pm UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012/5 "2017-06-10T20:24:10Z")
It should just be named `pi3-disable-bt.dtbo` and you can find it here: [https://github.com/raspberrypi/firmware/tree/master/boot/overlays](https://github.com/raspberrypi/firmware/tree/master/boot/overlays) It _should_ be there as standard in a Raspbian Jessie image. ---
**Author:** ![lucidman](https://avatars.discourse-cdn.com/v4/letter/l/34f0e0/32.png) [@lucidman](https://forums.pimoroni.com/u/lucidman)\ **Post date:** [June 10, 2017, 8:30pm UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012/6 "2017-06-10T20:30:13Z")
Success! I didn’t have the latest Raspian distribution. I do now. Thanks! ---
**Author:** ![PiguyAnge](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/piguyange/32/11560_2.png) [@PiguyAnge](https://forums.pimoroni.com/u/PiguyAnge)\ **Post date:** [June 25, 2017, 11:30pm UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012/7 "2017-06-25T23:30:26Z")
Is this also an issue with the Pi Zero ‘W’ as well? ---
**Author:** ![gadgetoid](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/gadgetoid/32/13_2.png) [@gadgetoid](https://forums.pimoroni.com/u/gadgetoid)\ **Post date:** [June 26, 2017, 9:12am UTC](https://forums.pimoroni.com/t/ttyama0-fails-with-phat-on-rpi3/5012/8 "2017-06-26T09:12:40Z")
Yes, I believe it is.