Does anybody have any idea where to look for this one? We have a custom LPC1788 design that has a TFT QVGA LCD and external sdram at 0xa0000000 - 0xa1ffffff.. If I point the LCD to external memory the debugger(Crosslink) will after about 15 seconds disconnect with the error "Memory read opration timed out." Here is the kicker if I disable the LCD it works just fine. Or if I point the display to internal memory all is good. Also there are other systems/code that use the external ram. So I am not sure if the ram is at fault. Also I did not have this problem with the Embedded Artist dev board using a Truly display. Our design uses a Tianma display. The debugger seems to work fine with the Truly timing and not the Tianma timing. One more weird point, the clock rate for the Tianma display is slower than the Truly, 6.4MHz vs 8.2MHz.
LCD used: Tianma TM035KDH03, chip Novatek NT39016D
CPU speed 120MHz, External bus 60MHz
Update Systems, Inc
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