Wishlist for a custom Transmitter board

I have built the powerswitch circuit, but i modified it a little. My unknown salvaged Pnp Transistor didnt switch, and my ao3401 was always on.
For now it works. But i have to check with a display. ssd1306 doesnt work (but Sadsack had a working version with crius oled which is a ssd1306 in my opinion).

I have ordered erc12864-2 from buydisplay, and need to make an adapter for it.
I´m not sure about the reset pin of the display. Do i need to connect it to the stm, or pull it up or down?

I haven't got any further with mine at all yet
My project has stalled due to other commitments that are going to be soaking up all my free time for at least few more weeks
(Fit a shower into the bathroom that has turned into a full on project due to unforeseen circumstances)

I have an SSD1306 and would be happy with that working for now

The other screen I was looking at (NT7538) is the right dimensions to the TX's 'window' so physically ideal
the seller sent me through a spec sheet and I don't understand the connections enough to say what I would need to do to make it work with the dev board - other than there are more connections on the screen than I have marked pins



Project stalled but not entirely abandoned

2hry wrote: I have built the powerswitch circuit, but i modified it a little. My unknown salvaged Pnp Transistor didnt switch, and my ao3401 was always on.
For now it works. But i have to check with a display. ssd1306 doesnt work (but Sadsack had a working version with crius oled which is a ssd1306 in my opinion).

I have ordered erc12864-2 from buydisplay, and need to make an adapter for it.
I´m not sure about the reset pin of the display. Do i need to connect it to the stm, or pull it up or down?

I was thinking on this also for some time, the pololu step/up down regulator do have an Enable pin. You can switch on the output or be in off, it has very low quisent current. A very simple solution could be to use a capacitor on the Enable pin? When switch off Tx, it keeps the pololu enabled for some extra seconds?
www.pololu.com/product/2122

It was somewhere on my todo list for 7e, to completely ditch the devo power circuitry and run it from 3v3 by 2 parallel NCR18650, charge it using usb, charge module tp4056 with protection circuit.

www.banggood.com/USB-Lithium-Battery-Cha...ySodMCFQcQ0wodan0KFw

Fernandez - that looks like it could be a neat and elegant solution!
Very tempted to get one as it will be infinitely neater and possibly cheaper then anything I can make up

Wish sadsack was still about to share how he got the oled working
Have tried messaging him via a few different channels as well as on here, but it seems he hasn't logged on anywhere recently
(not that I have been stalking him!)

My bathroom renovation is starting to draw to a close so hoping I can get back to the project once I get the all clear from 'she who must be obeyed' (hoping the dust and daily inconvenience has put her off dreaming up another time and money sapping project for another few years)

Regards
Rob

@Fernandez : Thank again for this link.

Your regulator and charge unit looks good !

I don't really understand the SSD1306 problem (I'm French) but I've build an optimised I2C driver for this Oled display :
github.com/Ingwie/OpenAVRc_Dev/blob/mast...d_ssd1306_driver.cpp

And we use JQ6500 module for Voice (2 wires only : UART TX and busy pin) :
github.com/Ingwie/OpenAVRc_Dev/blob/mast...cad%20.docx?raw=true

It need an extra SDcard for the MP3 files and is the faster i've tested. (We can't play MP3 with our "poor" M2560

Regards

Edit : With Slope-Soarer, we are in integration of Deviation "Cmds" code into OpenAVRC project.

stevecox wrote: FWIW other similar ideas now discontinued but some of the ideas, pitfalls could be used - Gruvin9x gruvinandco.com/shop/ and Sky9x openrcforums.com/forum/viewtopic.php?t=1497 and www.ersky9x.net
I actually have a Sky9x board in a 9x and was happy with it until Deviation. If Deviation had a board I wouldn't hesitate to get one. If it would help I would ship the tx anywhere for someone to poke around at.

Hmm from the Gruvin website ...
<Quote>You can still build your own G9X board!
The G9X v4.x boards are fully supported by Open-TX. Full design data (KiCAD) for the final version (v4.2d) is available here.
PCB's can be ordered ecconmically from ITead Studio (or your preferred prototype PCB supplier) by supplying them the Gerber files from within this zip file.</Quote>

can't agree more.

@Bracame
My problem with ssd1306 is: I am not a programmer + the goal is to flash precompiled software.

Update on the display: I have ordered Erc12864-2 from Buydisplay - It works but the display is mirrored, so it would need a code change.

In another thread, someone wrote the display has Uc1601 driver, and I ordered this one:
Link

And it works. But my board is rebooting every few seconds, and the missing module message is not going away when I press ok.

Hi, it's look like a watchdog reboot. EDIT (reboot)

I'm a developer on OpenAVRc not Deviation for this time.

STM32 was my playing board few years ago and I'm playing now with AVR ...

Will be happy to code on Deviation but I've a project to finish.

I got things working on the SSD1306. Code changes to the init script was required as well as a hardware pin for reset of the old on bootup. After that everything went well on the screen side.

I also ended up not being able to get out of the "Missing Modules" screen, as hitting "OK" would just reboot the board. Traced it down to somewhere in the MULTI_MOD stuff, so I disabled that for now as I don't have any rf_modules to hookup. I assume, it really doesn't like the fact that no modules are present.

So now it boots up (without the reboots), displays on the SSD1306 OLED screen and we can play around in the menus.

Connections for screen as follows:

SSD1306 -> MCU Port.IO#
CLK -> A.5
MOSI -> A.7
RESET -> B.1
D/C -> C.5
CS -> B.0

The file is attached here (I named it devo7c as in devo7custom) and it WILL ONLY work for a SSD1306 screen currently. It's based on the latest nightly.

That is fantastic news!
Have just ordered an SPI ssd1306 as the one I have is only I2C 4 wire

I do have a spare RF module (from my Devo 10 that now has a 4 in 1)

Can't wait for it to land so I can have a play!

@silpstream

Great, Thanks.

Would you share the code changes for the oled? So a noob can understand how to do that.

I would like to mirror my nt7538(Change A0 to A1 in the initialisation in lcd.h?)
Do you know how this works? I was already looking at adafruit libraries, but thats to much for me.

Yesterday i got a Robbe xs4 Transmitter, which I bought used (It is like a Walkera2402).
I salvaged the cyrf module and connected it. No more reboots. Bound with a Dsm2 Rx successful.

You can find the code on Github . Check the devoXc branch then look for the devo7c folder.

I'm not sure what you mean by mirrored. Your picture above looks ok to me or upsidedown depending on how you want to mount it. The SSD1306 code may not help you, it uses a different command set so the initialization is different.

Nice Job Silp !!!

OLED looks great.
This brings the custom TX closer follow with interest, can't wait to see the parts list for the full custom TX

OLED arrived
Hooked up, flashed the DFU....however I cannot format or do anything with USB on the board W25Q16 flash
Is there anyway that Moeders flash mods to the DFU can be merged with the OLED mods so it will work with this flash chip?

www.deviationtx.com/forum/7-development/...board?start=40#60057

I know its diluting the builds and asking a lot from those who can

I can see stuff on the screen...but unable to do much as no usable flash chip with fonts or ini's.... tantalizingly close

I will try the other board

@robocog, I don't really mind, I'm just not sure what he changed in the code. Will have a look.

@moeder, any chance you can share the changes you made? It'd make life a lot easier! ;P

github.com/DeviationTX/deviation/blob/ma...on/stm32/spi_flash.h

Is it a build time option?
(I am wildly stabbing in the dark here and am waaaay over my head and just quessing out loud)

I didn't write it, it was all done by mwm for his new 4-in-1 + flash board. But it's all there written (although not tested with all devos of course) and I just suggested we implement this especially for the devof12e-4mb builds. The code basically checks for chip id and size and sets all parameters accordingly. It should be pretty easy to make it work, but I don't have time for this for at least a couple of weeks so maybe someone else is willing to put effort in this, maybe even mwm himself?

@robocog, I'm taking a stab in the dark here since I can't test this. Could you try the attached file and let me know how it goes. Basically I activated the flash detection code for this build, but I've not looked extensively to what it does in the background. *fingers crossed*.

IT WORKS!!!!
I have a working screen and can use the flash drive
(Just got up for work and spotted your reply so fired everything up to test as there is no way I could do a days work without trying it)

Can't thank you guys enough for this

Regards
Rob

Will an ssd 1309 oled work with this ?
Found them quite cheap and having a larger screen would fill the window a bit better

Regards
Rob