LCD panel init problems
Quentin email (remove spam text)
"Wollenberg, Frank" wrote:
> The command "function set" (0x30) is a regular command, which can be send to
> the LCD at anytime in two 4bit chunks, 0x3 followed by 0x0.
> How can the LCD differentiate between this regular command and the command
> as part of an initialisation sequence ?
Think of it this way:
0x030 => b'00110000'
Your 4 bit data line is connected to the 4 MSB data lines of the LCD.
The other 4 LSB of the LCD is tied to gnd.
So, when you put the MSB of b'0011' on the LCD there is already b'0000'
on the 4 LSB of the LCD (connected to gnd)
So in actual fact you are sending 8 bit data.
Sending b'0011' and the LCD thinks you are actually sending b'00110000'
After you did this 3 times, you tell the LCD, OK, now we are going to
use 4 bit comms.
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