PIC 16f877a alarm clock

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LrAk07 said:
Alarm clock with PIC (Thomas' Webpages)


could someone help me with this.. I don't understand why the other capacitors and resistors in the schematic diagram have no value.. and only 10 pins of the lcd is used.. please help me..
Click to expand...

hi,
I have added the values I would use.
Did the link have a Parts List file.???

The MAX232 is a dual TXD/RXD device, only one pair is used, thats why the other pins are not connected.
 

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Thanks for the values you indicate in the schematic, i will try to use that resistors & capacitors..
I didn't find any parts list in this link but only in the schematic..

thanks again for info in max232.. i have another question, he only use 10 pins of the 4x20 LCD but the LCD has 16 pins.. I want to know what pins did he use, could you help me?..
 
Just guessing: he is using 4 bits only in the data bus? For the other two not used, I cannot guess anything.
 
atferrari said:
Just guessing: he is using 4 bits only in the data bus? For the other two not used, I cannot guess anything.
Click to expand...

thanks atferrari!.. I think he only use 4 bits and the other 6 pins would be from the ground which is pin1 up to clock(enable) which is pin6..
 
LrAk07 said:
thanks atferrari!.. I think he only use 4 bits and the other 6 pins would be from the ground which is pin1 up to clock(enable) which is pin6..
Click to expand...

hi,
As you have seen, LCD 4 data lines, Enb and RS lines. [with the R/W line to 0V..??]
The backlight line is driven from the transistor and 50R.

I would check how the Vcontrast line is connected.???
 
Just a suggestion,

This AL clock may not interfaced with a LCD but its better than that JAL clock

**broken link removed**
 
ericgibbs said:
hi,
As you have seen, LCD 4 data lines, Enb and RS lines. [with the R/W line to 0V..??]
The backlight line is driven from the transistor and 50R.

I would check how the Vcontrast line is connected.???
Click to expand...

Have you checked the connections from pic to lcd?.. i think my connections was right, i looked at the images of the finished project..
 
hi guys,
am doing a project on clock trigger device. in that am planing to give a transformer less(cost effective) power supply is their any major problem can occur, didnt work with such kind of power supply. will thankful for your opinion.

regards
thomasplam
 

1. Don't use a transformerless supply, it's very dangerous.
2. Start your own thread, don't hijack this one.
 
I already try the project but the LCD's output was blocks and blinking.. I think it is running, but there are no data that was input to the LCD.. Can someone help with this problem..
 
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