I had seen the OpenTx Mega 2560 by some diy people on Rc group .I was wondering if anyone here tried it.I know that 8 bit is a little bit old.but I am hoping someone to have tried it here
Since nobody replied,I am posting here for other who want to build a diy transmitter
https://youtu.be/q7gNuaYw5Y4 (https://youtu.be/q7gNuaYw5Y4)
https://youtu.be/I_5i-iswQvg (https://youtu.be/I_5i-iswQvg)
Yups the m2560 ones are cool. currently building one as well.
http://www.rcindia.org/self-designed-diy-and-college-projects/flying-on-a-3d-joystick/
Quote from: ghoshatanu56 on June 21, 2017, 04:57:12 AM
I had seen the OpenTx Mega 2560 by some diy people on Rc group .I was wondering if anyone here tried it.I know that 8 bit is a little bit old.but I am hoping someone to have tried it here
Yes the 8 bit arch is a little bit old but it still takes care of what most people want unless you're planning to do any real-time video processing etc
What LCD screen are you using? the JHD12864E types have a different pinout to work with the m2560 based tx
Yes sir you were first in the forum to try mega2560 .I have seen your video using a liner pot( not rotary ones)and another joystick. It came up when I was searching opentx mega in YouTube.
I am using one with st7920 LCD.
Mine with diy multiprotocol module works great
Wow nice :thumbsup:
What module are you using .?
nrf24l01 and cyrf6936 2.4g transmission module
Works with spektrum dsmx protocol
N Chinese protocol on wltoys n hisky
hi folks,good evening , I am new to RCindia
i am trying to build a opentx transmitter with mega2560 with lcd 12864b v.2
i am able to read and write models using open tx companion
connecting using the schematics from opentx
i build the firmware with mega and st7290 but after uploading the firmware and writing through opentx, my lcd is blank
but lcd is working u8glib library with arduino
I dn know why its not working with opentx, need help.
Thanks in advance
Welcome to rci!
I'd troubleshoot in this order..
1) contrast adjustment
2) pinout mapping from 2560 to LCD. the st7920 does not need a CS2 pin connection, it needs not be connected.
3) the required pinout is specified in the MEGA2560_sch.pdf
I have created header boards (shields) that take the 2560 on one side and the ST7920 + the pots and switches on the other side. You can study these for the connections or download the plans and build one for yourself from the link below. If you do not want to build, i have some already fabricated available with me.
https://github.com/gtgs/gt-jtx/tree/master/gt-jtx-2560/hardware
All the best!
thank for helping us out sir i tried with the following configuration, but still have the same problem i followed your troubleshooting guide but still the problem exist
LCD 12864B V 2.0 PIN ARDUINO MEGA 2560 PIN
GND GND
VCC +5V
VOUT NC
RS 32
R/W 31
E 30
DB0 22
DB1 23
DB2 24
DB3 25
DB4 26
DB5 27
DB6 28
DB7 29
PSB +5V
NC NC
RST 33
VOUT NC
BLA 5V
BLK GND
1. Use a potentiometer for the contrast adjustment pin.
pin1 - +5v
pin2 - VADJ pin of LCD - see below
pin3 - GND
2. try the pinout below for the ST7920
LCD 12864B V 2.0 PIN ARDUINO MEGA 2560 PIN
GND GND
VCC +5V
VADJ center pin of potentiometer
RS 32
R/W 31
E 30
DB0 22
DB1 23
DB2 24
DB3 25
DB4 26
DB5 27
DB6 28
DB7 29
PSB 34
NC NC
RST 33
VOUT NC
BLA 35
BLK GND
3. After powering up, see if the LCD lights up (Backlit LED). If open tx is working, the backlight should turn off after a while. if it doesnt turn off, check your program code and if it is flashed correctly. if the backlit LED turns off, check the LCD contrast.
4. Use a multimeter (continuity tester mode) to see the connections and wires are correct.
5. Wire up the other components also, the pot/sticks/switches etc... would recommend not to leave any pins floating before powering up
You will need to be very patient with the setup. it can take a lot of time for debugging so dont give up :D
Thank you for the help,
i ll try the things u have said and update .