Hi gnoemli,
yes correct, the HD44780 is a nightmare regarding its timing. Most people use software based delay routines between writes to the HD44780. However, the most efficient way of talking to the HD44780 is to read back the control register of the controller after having written anything to the date/controlregister. As long as the highest bit is set the controller is busy with the last character / function. Unfortunately the controller has no hardware pin to signal this information, so you will have to make yourself a routine that checks the controller say every 1 millisecond or so for being ready.
regards Ulrich
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Hi there
>
> i have to interface an lcd (hitachi HD44780 based controller) to a dsp
> (tms320c6713b from ti).
> the problem is that the lcd controller is very slow in accepting data.
> in order not to use too much of the dsp resources, i don't want to
> introduce any wait states in the dsp.
> other peripherals are also connected to the emif, so i don't want to
> slow down the emif either.
> has anyone an idea how to interface the lcd with the dsp?
>
> thanks a lot for any suggestions, you'd help me a lot.
>
>
> gnoemli
>