Do you mean "standard ASCII" control characters in the range of 0 through 31, or do you mean "standard HD44780" control codes (with the LCD RS pin set to 0)?Mike,
I downloaded the code and had a look at it, but as I previously posted, I know next to nothing about asm. Does your code have the provision for sending "standard" control characters to the LCD?
Thanks.
The HD44780 accepts any 8-bit value, 0-255, but my backpack traps any character with a value of 0xF0..0xFF (240-255) and uses it to set a flag to indicate that the following character should be written to the LCD with the RS pin set to 0 (an HD44780 control code).