Skip to content
Commit 35b464e3 authored by Hugo Villeneuve's avatar Hugo Villeneuve Committed by Miguel Ojeda
Browse files

auxdisplay: hd44780: move cursor home after clear display command



The DISPLAY_CLEAR command on the NewHaven NHD-0220DZW-AG5 display
does NOT change the DDRAM address to 00h (home position) like the
standard Hitachi HD44780 controller. As a consequence, the starting
position of the initial string LCD_INIT_TEXT is not guaranteed to be
at 0,0 depending on where the cursor was before the DISPLAY_CLEAR
command.

Extract of DISPLAY_CLEAR command from datasheets of:

    Hitachi HD44780:
        ... It then sets DDRAM address 0 into the address counter...

    NewHaven NHD-0220DZW-AG5 datasheet:
	... This instruction does not change the DDRAM Address

Move the cursor home after sending DISPLAY_CLEAR command to support
non-standard LCDs.

Signed-off-by: default avatarHugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Tested-by: default avatarDavid Reaver <me@davidreaver.com>
Link: https://lore.kernel.org/r/20230722180925.1408885-1-hugo@hugovil.com


Signed-off-by: default avatarMiguel Ojeda <ojeda@kernel.org>
parent 2ccdd1b1
Loading
Loading
Loading
Loading
0% Loading or .
You are about to add 0 people to the discussion. Proceed with caution.
Please register or to comment