I am a newbie in Arduino development. I am trying to use Arduino Uno + U8G2 lib + EA Dogm128 monochrome display. The thing is that it doesn't work.
I am using the basic HelloWorld example to get started. The display doesn't show anything. I have only a basic multimeter so I can only measure the DC on single pins.
I have 2x1.5V batteries (that actually supply 3.1V in series). I was using a level translator from 5V->3V but after some static test I noticed it had voltage degradation problems on many pins (maybe the soldering went wrong) so I am currently doing the test in 2 steps (1) load the sketch from PC into Arduino (2) i disconnect arduino from USB cable and power it with the battteries which power the rest of the circuit.
I am using the proper backlit led panel suggested by the manufacturer with 3 series resistors as current source.
The constructor i am using from U8G2 is.
U8G2_ST7565_EA_DOGM128_F_4W_HW_SPI u8g2(U8G2_R0, /* cs=/ 10, / dc=/ 9, / reset=*/ 8 ) ;
I am attaching the connections I made as image.
BLACK Chip Select, WHITE Reset, GRAY Data/Command, PURPLE Serial Clock, BLUE MasterOutSlaveIn.
The following is the connection scheme I have adopted more or less.
The level translators are missing because of the reason I said above. The reset pin is directly connected to the pin specified in the class constructor instead of being pulled up by 10k resistor.
I do not have a digital scope right now so I do not know what to check with a voltmeter.
Do you have any idea?