Quote from: iv_pb on October 13, 2020, 07:43:40 PM

@Rudloph - Thank you for checking.

Am I reading this wrong?

//BRT_AN_033_BT81X_Series_Programming_Guide.pdf

5.5 ROM and RAM Fonts
In the BT815/6, fonts are treated as a set of bitmap-graphics with metrics block and used by the
following co-processor commands, indexed by bitmap handles 0 to 31:
- CMD_BUTTON
- CMD_KEYS
- CMD_TOGGLE
- CMD_TEXT
- CMD_NUMBER

For any EVE series ICs before BT81X Series, each font supports up to 128 ASCII characters.
In addition to ASCII character support, BT81X Series introduces extended font metrics format to
support a full range of Unicode characters with UTF-8 coding points.

Yes, I do agree that this strongly implies that CMD_KEYS supports UTF-8 chars.
However, every other command explicitly states that it supports UTF-8, like in chapter 5.12 on page 105.
The only exceptions are CMD_KEYS which does suprise me a little, and CMD_NUMBER which should never use anything else than numeric chars.

As evidently UTF-8 does not work with CMD_KEYS my guess would be that this is an oversight in the programming guide for chapter 5.5., unless there is something else to activate it, like an undocumented flag for the options field.