Hello everyone,
I'm new to the Arduino world and come from the Raspberry Pi one always used more as a computer replacement than a real low level microcontroller.
Lately I'm becoming interested in this world and I have a background know-how from pc modding and eletronic in general but completely new to this one. I'm reading many articles and tutorial and I'll receive soon many components.
My first project idea, being a fan of old-style phone, was to built a fully functional GSM phone with keypad and a simple LCD or OLED for both sms and calls. Actually I got two UNO boards both v3, a generic kit with the classic dual line blue backlighted LCD many components, also another official starter beginner kit. I'll get soon:
-a generic NANO v3 board
-a 16 buttons keypad,
-the OLED 128x64 display (but with no library as much as I read after bought it),
-a SIM800L module with SPK and MIC points (don't know if 5V fixed or the old one I'll see),
-a DC-DC step down LM2596 2A regulator,
-a DC-DC step up 2A MT2608 (up to 5V-28V) regulator,
-already have many 3,7v LiOn phone batteries I could use,
-a 4 AA Ni-Mh battery holder case if I'd go for a 6v/4,8v alternative
-a TP4056 LiOn protection chargers
-10K ohm resistors (someone said it's needed for the TX line from the arduino to the SIM800 module to reduce Vin HIGH)
etc...
Now, beside how much it will be difficult to write the code I'd like to begin understanding some things and once I'll receive the components I'll update here with more questions.
To begin:
1) if I use the DC-DC step UP regulator can I use ONE single li-on 3,7v 1500mah (ex.) battery to give power to both the arduino (uno or nano) AND the SIM800L board? I understand the gsm module will ask up to 2A of power so I imagine I can't use the 5v or 3.3v lines from the arduino itself. Or maybe it is better to power the arduino with a 9V classic battery and a 3,7v big battery for the gsm module separately? Cause if I use the NANO I can't use the 9V without the step-down converter, if I use the UNO everything will become big and not good looking for modern phone and I still have to find a good looking plastic case.
2) to use the classic LCD (with the dual asic on the back the one with the starter official kit) do I need some serial converter or external module to write to it? And the generics oled display does need some serial converter too?
3) beside the youtube tutorials, someone here has built a good stable and functional similar project with a clear guide to follow? I've seen many choosed different roads for both wirings and codes.
Thanks for the initial answers.
Bye