Hi,
I'm building an LCD circuit for a rackmount PC. I have a standard HD44780 20x2 display.
I want to be able to display a menu on the screen when the PC is off, allowing you to boot into one of several modes. But when the PC is on, I want LCDSmartie to have control of the display.
LCDSmartie uses 8 bit control, so needs 11 control lines.
I was thinking I have three options, either:
> I put a set of cmos switches in line with the control signals and then use the PICAXE to switch between the computer's printer port or the PICAXE output.
> Use a large chip such as the 28X and setup it to have 11 inputs and 11 outputs and then use another chip to control it over serial (and have the chip sit acting like a buffer when the computer wants to control it)
> Write PICAXE software that can control the LCD or accept serial input from the computer as needed.
Any reccomendations to the best approach?
I'm building an LCD circuit for a rackmount PC. I have a standard HD44780 20x2 display.
I want to be able to display a menu on the screen when the PC is off, allowing you to boot into one of several modes. But when the PC is on, I want LCDSmartie to have control of the display.
LCDSmartie uses 8 bit control, so needs 11 control lines.
I was thinking I have three options, either:
> I put a set of cmos switches in line with the control signals and then use the PICAXE to switch between the computer's printer port or the PICAXE output.
> Use a large chip such as the 28X and setup it to have 11 inputs and 11 outputs and then use another chip to control it over serial (and have the chip sit acting like a buffer when the computer wants to control it)
> Write PICAXE software that can control the LCD or accept serial input from the computer as needed.
Any reccomendations to the best approach?
