I'm using the screen in 4 bit mode so I have DB4-7 hooked up to GPIO 0-3 respectively.
I have also hooked up RS, R/W and E to other GPIO pins.
I can see the function set binary string is 001010xx to set 4 bit mode with 2 display lines and 5x8 dots display mode. I am thus setting the GPIO 0-3 pins to 0010 and then setting the enable pin high. I set the enable pin back to low and set the GPIO 0-3 pins to 1000. Again, I pulse the enable pin.
All the time, the RS and R/W pins are low to signify Instruction Input & Write, respectively.
I've tested the pins output with a multimeter so I'm confident that they are high and low when they should be... however it's just not working. The screen does not change to 2 lines nor can I send 4 bit commands in a similar way, following this.
Anyone have any insights?