maxfed3 Posted May 29, 2018 Share Posted May 29, 2018 (edited) Hi All! OS - ARMBIAN 5.38 stable Debian GNU/Linux 9 (stretch) 4.14.18-sunxi OPI Zero. armbianEnv.txt : overlay_prefix=sun8i-h3 overlays=uart2 param_uart2_rtscts=1 RTS CTS don't work I check the work of the logical analyzer. The line RTS does not change the voltage during the request for data transmission. This is necessary for me to connect the MAX485 chip to UART2 OPI Zero. Edited May 29, 2018 by maxfed3 Link to comment Share on other sites More sharing options...
martinayotte Posted May 29, 2018 Share Posted May 29, 2018 Right, looking at source of sun7i-a20-uart2.dts overlay, it seems that rts/cts pins are not managed as it should ... Link to comment Share on other sites More sharing options...
maxfed3 Posted May 29, 2018 Author Share Posted May 29, 2018 What solutions are available? Link to comment Share on other sites More sharing options...
martinayotte Posted May 29, 2018 Share Posted May 29, 2018 No easy one ... The following piece of DT need to be added to "pio" of the main DT. Maybe that could be done with an overlay, but still requires some work ... uart2_rts_cts_pins: uart2_rts_cts { pins = "PA2", "PA3"; function = "uart2"; }; Link to comment Share on other sites More sharing options...
zador.blood.stained Posted May 29, 2018 Share Posted May 29, 2018 5 hours ago, martinayotte said: Right, looking at source of sun7i-a20-uart2.dts overlay, it seems that rts/cts pins are not managed as it should ... Are we talking about A20 or H3? Link to comment Share on other sites More sharing options...
martinayotte Posted May 29, 2018 Share Posted May 29, 2018 @zador.blood.stained Since OP mentionned OPiZero in the title, I presume that current patch "sunxi-h3-h5-uart3_rts_cts_pins.patch" should be extended for uart2 also ... But the "sun8i-h3-fixup.scr" would also need to be extended too ! Link to comment Share on other sites More sharing options...
maxfed3 Posted May 30, 2018 Author Share Posted May 30, 2018 When will it be possible to enjoy the normal operation of RTS and CTS UART2 ? Instructions for applying patches will be required. Link to comment Share on other sites More sharing options...
martinayotte Posted May 30, 2018 Share Posted May 30, 2018 I'm not sure "when". We will try to add that soon ... Link to comment Share on other sites More sharing options...
maxfed3 Posted June 4, 2018 Author Share Posted June 4, 2018 how are things with RTS and CTS UART2 ??? Link to comment Share on other sites More sharing options...
martinayotte Posted June 4, 2018 Share Posted June 4, 2018 Didn't get change to work on it yet ... "Time is the missing ingredient" ! Link to comment Share on other sites More sharing options...
maxfed3 Posted July 16, 2018 Author Share Posted July 16, 2018 If I put the latest updates, then the problem with UART2 will be solved? Link to comment Share on other sites More sharing options...
martinayotte Posted July 16, 2018 Share Posted July 16, 2018 I've done this fix to patches : https://github.com/armbian/build/commit/e0382d1ad2e5ac2c8d4dda814949f989812be18c#diff-33d9868ed154988dc938219a3df6f54d But I've not got chance to test it. BTW, this is for the "sunxi-next" builds ... (I will do the same for "sunxi-dev" today) Link to comment Share on other sites More sharing options...
maxfed3 Posted July 16, 2018 Author Share Posted July 16, 2018 Since I have not previously done this kind of work, you will need an instruction How to install these patches on the specified system but, I will be able to check the operation of RTS and CTS signals Link to comment Share on other sites More sharing options...
martinayotte Posted July 16, 2018 Share Posted July 16, 2018 Since the Armbian doesn't have a recent "next" build in https://dl.armbian.com/orangepizero/ , you will need to build your own image using procedures explained here : https://docs.armbian.com/Developer-Guide_Build-Preparation/ Link to comment Share on other sites More sharing options...
Recommended Posts