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Author Topic: TX light stays on (do I need to program a new FTDI chip?)  (Read 1329 times)
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I am testing a clone of an arduino I made for a personal project that essentially used the deuminalove pcb layout/parts/schematic as the basis.

Everything powers up and the FTDI chip can be ready by my computer. However, the TX light stays stuck on the pcb and I am unable to send or receive serial messages from my arduino.

I bought the FTDI chip new from Mouser. Do I need to program the eeprom on it?
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Does it stay lit if you remove the ATmega chip?  The FTDI chip should not need programming, and if your PC recognises it that's a good sign.  It could be that the AVR chip has its serial pins configured as high outputs, forcing the serial LEDs on.
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It could be that the AVR chip has its serial pins configured as high outputs, forcing the serial LEDs on.

No, the FTDI uses different pins for the rx/tx leds then the signal lines it uses for tx/rx to the AVR chip. They are not electrically connected and do not simple reflect the electrical value of the pins 0 and 1 state.


Lefty
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yeah the TX light stays on whether a atmega is plugged in or not.

However, I did notice that the problem seems to occur when powering off of the USB jack. When I am powering from external source it is not staying on.
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