Content originally posted in LPCWare by irvind on Tue Jan 08 21:47:37 MST 2013
According to LPC1788 specification,
LCD need LCD_VD[15:12] for green color, LCD_VD[23:20] for blue color. (minimum requirement)
QEI_PHB pin assigned to P1.23
LCD_VD[13] assigned to P1.23 or P1.27
LCD_VD[21] assigned to P1.27
So if you need to use QEI_PHB function, P1.23 won't be an option for LCD_VD[13], it can only assign to P1.27. Which have conflict with LCD_VD[21] that only can use P1.27.. HOW COME NXP NEVER MENTION no QEI if you need TFT LCD IN DATASHEET!!!!!!!!!!!
Below is their "detail" reply. They even get confused with my part number...
[B][I]Thank you very much for contacting NXP Semiconductor.
It appears that the configuration required by you cannot be achieved on the LPC1768. This is because of the pin multiplexing limitation.[/I][/B]
Anyone got idea how to achieve it? I can achieve it by killing 1 bit of green color, which I think not an ideal solution.