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Topic: 2.4 TFT LCD helpp (Read 4159 times) previous topic - next topic


Thanks for the readreg output.   This makes a lot more sense than your earlier report in #5.

You have an ST7781 controller which is (or was) fairly common.

I suggest that you post a schematic of your "current reading" circuit.

Most importantly,  you should explain how you derived your calculations.



Hi david this is how I got my calculation.. pardon for my writing erasures..


Feb 17, 2017, 01:46 pm Last Edit: Feb 17, 2017, 01:49 pm by david_prentice
Think about it.  You charge batteries with Solar cells.   
You want to know the voltages produced by the Solar cells.   
You want to know the battery voltage.
You want to know the charging current from the Solar to the battery.
You want to know the load current supplied from the battery to your actual appliances.

The current in the measuring circuit is trivial i.e. 225uA.   Your battery is probably going to self-discharge faster without any load at all.

Draw the whole circuit.   Then draw arrows with a pencil.   i.e. where each current flows in the network.
Then think about how to do the measuring.  Where to place any sense resistors.

I presume that you have all been studying for your University degrees.   You should be able to analyse networks.   Do Ohm's Law and Kirchoff's Law calculations.    Your whole group should sit down together.   Discuss how to do your project.

The Internet is very useful.   Read App Notes from Solar Cell and battery manufacturers.   Read projects from other students.   It is your job to do the studying.
It will also help when you get your first paid job.   i.e. how to find and learn from other peoples' work.
It is no good expecting people to do your school project for you.   
Ask questions.   Show that you have made some effort.


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