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I am getting a problem while burning the code in LPC2148 interfacing with GLCD. Flash Magic is showing an error- failed to autobaud. I want to know if we can directly connect GPIO pins of LPC2148 to 8 pin data bus of 128*64 GLCD???? Please reply immediately or as soon as possible...... I have to summit my project within a week.
"Would we know what voltages you supply the processor and the GLCD with? - i have tested voltage supply. It is 3.6 V on the processor."
Interesting. Are you really sure that you should power the processor with 3.6V? The nominal voltage to the processor is 3.3V and 3.6V is an "Absolute Maximum Rating" value. So instead of having 0.3V safety margin, you power the processor with a voltage where the slightest manufacturing precision of the voltage regulator or temperature drift will push the voltage outside the allowed range.
Next thing: Didn't you notice that my question said "and the GLCD"? So why did you not tell us what voltages it gets?
"Would we know if the processor have a proper reset circuit? - yes reset circuit is correct. i have tested this." How have you tested this? Was there any difference when the GLCD was connected or not? Do spend some words on actually describing what you have done instead of just giving us your conclusions. Your device doesn't work, so your conclusions may be wrong.
"Would we know what you do with the external interrupt pin used to request that you want to enter programming mode? - Sorry, but i didn't get this." I take it then, that you haven't read the user manual for the processor, regarding the requirements for the processor to stay in the boot loader and wait for someone to upload a new firmware using Flash Magic?
There is a full chapter covering the flash memory. One thing to note there is:
A LOW level after reset at the P0.14 pin is considered as an external hardware request to start the ISP command handler.
"- I haven't tested or spent time on oscilloscope." Any reason why? You don't own an oscilloscope? So if not - then what other tests have you done on the individual pins of the processor to compare what differs if the GLCD is connected or not?
"Would we know if you have selected to use any series resistors for signals between processor or GLCD?" - I haven't used any resistor. They directly connected without any intermediate components.
Remember that some signals are dual-direction. So if your processor happens to have the IO-pins still set as outputs when the GLCD thinks it's time to send data to the processor (which is the reason for the R/W signal) then the processor and GLCD will fight. That is a good reason to make use of a series resistor to reduce the currents involved. Another thing is that the processor pins may be 5V tolerant, but that is only when the pins do not fight with some external hardware at the same time. The datasheet mentions short-circuit currents of up to -45mA and +50mA for a single pin.
"What have you done in response to processor note for P0.2 and P0.3? - The data bus pin of GLCD are connected to the P0.2 and P0.3."
Yes - you have already told us that P0.2 and P0.3 are connected to the GLCD. But what about the note in the processor documentation about P0.2 and P0.3 that can be found in both datasheet and user manual for the processor? The note [3] for these two pins says:
I2C Pad; 400kHz Specification; Open Drain; 5V Tolerant.
Open Drain might be something for you to consider.