I already made topic about this at gbdev.gg8.se forum, but this forum seems more active.
There is this caution in Pan Docs (http://gbdev.gg8.se/wiki/articles/Video_Display#LCDC.7_-_LCD_Display_Enable):
However, in leaked official Nintendo Game Boy Programming Manual (version 1.0, released 11/09/1999) it's not mentioned that it can cause any hardware damage, only that "a black horizontal line appears on the screen" if LCD turned off outside of VBlank interval (except on Game Boy Color, where it's safe). Also it says that it's 'recommended', not 'required'.
In the end, which one is correct?
There is this caution in Pan Docs (http://gbdev.gg8.se/wiki/articles/Video_Display#LCDC.7_-_LCD_Display_Enable):
Quote:
CAUTION: Stopping LCD operation (Bit 7 from 1 to 0) may be performed during V-Blank ONLY, disabeling the display outside of the V-Blank period may damage the hardware. This appears to be a serious issue, Nintendo is reported to reject any games that do not follow this rule.
However, in leaked official Nintendo Game Boy Programming Manual (version 1.0, released 11/09/1999) it's not mentioned that it can cause any hardware damage, only that "a black horizontal line appears on the screen" if LCD turned off outside of VBlank interval (except on Game Boy Color, where it's safe). Also it says that it's 'recommended', not 'required'.
In the end, which one is correct?