add SHOW_CUSTOM_BOOTSCREEN support to HD44780

[ellensp]

Description

Adds SHOW_CUSTOM_BOOTSCREEN to text LCD's (HD44780)
The custom boot screen can include up to 8 custom 5*8 pixel characters

Eg

Requirements

A Text based LCD display, SHOW_CUSTOM_BOOTSCREEN, and a properly configured _Bootscreen.h

Benefits

Adds SHOW_CUSTOM_BOOTSCREEN to text LCD's

Configurations

EG Configuration files for RAMPS + REPRAP_DISCOUNT_SMART_CONTROLLER and _Bootscreen.h

Related Issues

I'm sure this has been asked for a number of times, but cannot quickly locate an issues for it

NOTES:

Need somewhere to put the example _Bootscreen.h for users to find and base theirs on.

Stock Configuration_adv.h needs updated to allow setting SHOW_CUSTOM_BOOTSCREEN with HAS_MARLINUI_HD44780

[thisiskeithb]

Need somewhere to put the example _Bootscreen.h for users to find and base theirs on.

We have an "AnimationExample" folder in the Configurations repo, so one could be added for this.

[ellensp]

There should probably be a _Bootscreen.h page in the documentation, that documents all the current 128x64 options and the new 20x4 options

[thinkyhead]

Presumably the call to goto_screen after showing the custom boot screen will revert to either Status Screen or Menu custom characters (for LCD_PRINTER_INFO_IS_BOOTSCREEN). So I just moved the new code to set_custom_characters. I also applied more specific names…

TERN_(HAS_CUSTOM_BOOT_CHAR_0, createChar_P(0x0, customBootChar0));

…so you'll want to adjust your example custom boot screen to match these updated names.

[ellensp]

Updated _Bootscreen.h example _Bootscreen.zip

[thinkyhead]

I've adjusted the code to just use the single array customBootChar[][8] containing all the custom characters.

customBootChars

/**
 * Up to 8 custom characters of 5 x 8 pixels
 * Use an online editor such as https://maxpromer.github.io/LCD-Character-Creator/
 */
const static PROGMEM byte customBootChars[][8] = {
  {         // '\x00'
    B00100,
    B01110,
    B11011,
    B01110,
    B10101,
    B01110,
    B00100,
    B00100
  }, {      // '\x01'
    B00001,
    B00001,
    B00011,
    B00010,
    B00110,
    B10100,
    B11100,
    B01000
  }, {      // '\x02'
    B00000,
    B00000,
    B00011,
    B00100,
    B01000,
    B01000,
    B10001,
    B10001
  }, {      // '\x03'
    B00000,
    B11111,
    B00000,
    B00000,
    B00000,
    B00000,
    B10001,
    B10001
  }, {      // '\x04'
    B00000,
    B00000,
    B11000,
    B00100,
    B00010,
    B00010,
    B10001,
    B10001
  }, {      // '\x05'
    B10000,
    B10000,
    B10000,
    B01000,
    B01000,
    B00100,
    B00011,
    B00000
  }, {      // '\x06'
    B00000,
    B00000,
    B00000,
    B10001,
    B01110,
    B00000,
    B00000,
    B11111
  }, {      // '\x07'
    B00001,
    B00001,
    B00001,
    B00010,
    B00010,
    B00100,
    B11000,
    B00000
  }
};

I'm also thinking the boot screen string may be better defined with strings instead of char arrays (PROGMEM strings stored as a PROGMEM array of string pointers):

#define CHR0 "\x00"
#define CHR1 "\x01"
#define CHR2 "\x02"
#define CHR3 "\x03"
#define CHR4 "\x04"
#define CHR5 "\x05"
#define CHR6 "\x06"
#define CHR7 "\x07"

const char * const custom_boot_lines[] PROGMEM = {
  PSTR(CHR0 " CUSTOM BOOT " CHR2 CHR3 CHR4),
  PSTR(CHR1 " SCREEN TEST " CHR5 CHR6 CHR7)
};

So custom_start_char[n] is a pointer stored in PROGMEM and both the pointer and chars would be fetched with code like this (similar to the code for M111)…

PGM_P const pstr = (PGM_P)pgm_read_ptr(&custom_boot_lines[i]);
const lchar_t c = (lchar_t)pgm_read_byte(&pstr[i]);

[ellensp]

I used char arrays for ease of design. With chars you can easily see in code where each char will be on the display, with strings you have to count spaces to align data to where you want it. But perhaps its not as bad as I imagined ...

[thinkyhead]

I used char arrays for ease of design.

Although _Bootscreen.h is likely to be generated by a tool, it can't hurt to make it more Human-readable. Using strings (where the boot screen contains no custom chars) the alignment will be easier to see at a glance. Adding custom chars hampers readability unless the custom chars are in the same positions on all lines, which is no guarantee. So I think double-quoted strings are nicer here than char arrays.

Here's the updated _Bootscreen.h that works with the applied changes.

[thinkyhead]

Another minor update. Of course character 0 has to be treated specially because it's a string terminator. So I just redefined CHR0 as '\x08' (BAK) and that character is replaced during screen drawing. Tested in the simulator.

_Bootscreen.h

[ellensp]

link to _Bootscreen.h is a 404 error for me.

[ellensp]

If using

const char * const custom_boot_lines[] = {
  PSTR(CHR0 " CUSTOM BOOT " CHR2 CHR3 CHR4),
  PSTR(CHR1 " SCREEN TEST " CHR5 CHR6 CHR7)
};

Works on sim, but will not build on 8 bit AVR

Marlin/src/lcd/HD44780/../../../_Bootscreen.h:49:3: error: statement-expressions are not allowed outside functions nor in template-argument lists
PSTR(CHR0 " CUSTOM BOOT " CHR2 CHR3 CHR4),

[thinkyhead]

The current _Bootscreen and code is fine. Those errors are from an earlier iteration. The link to the file works for me, so perhaps refresh the page.

[thinkyhead]

Is this flag known also known be needed for macOS? I know we just added it for Windows. Maybe some Linux need it too…?

[thisiskeithb]

On current bugfix-2.1.x / without this PR, both simulator_macos_debug and simulator_macos_release environments build the default Simulator config fine on my Intel-based Mac.

[ellensp]

Not required on Ubuntu 22.04.4 LTS or Ubuntu 24.04 LTS

[thinkyhead]

Sometimes macOS needs it, and probably it's ok to use the flag on Linux, or does it complain?

[ellensp]

The example _bootscreen link is now working..

At the time I refreshed and even vpned out to another country and tried the link from there,, it was broken.

[ellensp]

This works as expected.