Not wanting to delve into C programming just yet (I had to do some C++ at uni and didn't get very far!), I have been trying to approach the problem with just Perl. This is what I have got.

use strict;
use warnings;
use RPi::SPI;

# Initialize SPI: bus 0, 8 MHz
my $spi = RPi::SPI->new(0, 8000000);

# Reset display (if necessary)
sub reset_display {
    # Handle reset
}

# Send command to the display
sub send_command {
    my ($cmd) = @_;
    my $data = \[ $cmd ];  # Create an array reference for a single co
+mmand byte
    print "Sending command\n";
    $spi->rw($data, 1);  # Send command via SPI
}

# Send data to the display (ensure data is an array reference)
sub send_data {
    my ($data_ref) = @_;
    print "Sending data\n";
    $spi->rw($data_ref);  # Send data via SPI
}

# Initialize the display (according to the display's datasheet)
sub init_display {
    send_command(0x01);  # Command: software reset

}

reset_display();
init_display();

[download]

I'm getting an error from $spi->rw($data, 1); that doesn't seem to make sense. The error is data param must be an array reference but the RPi::SPI documentation says that rw takes buf (arrayref) and len (integer). It doesn't mention a data parameter and I am giving it an arrayref and an integer!

I've searched the source code and the error text is not there.

Some help debugging this would be appreciated please

In reply to Re: ST7789V2 LCD Controller by Bod
in thread ST7789V2 LCD Controller by Bod

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