now 3 hours has gone .. and its working ,,,, excellent !!! =)
Quote from: boraciner on Jun 17, 2012, 09:35 pmnow 3 hours has gone .. and its working ,,,, excellent !!! =)You definitely risk destroying the Arduino or the GPS (or both) - its not worth it. You probably have already compromised the performance of the Arduino pin by overheating its protection diode and nearby transistors. You may also be powering the Arduino's 3V3 rail through that diode and raising it to more like 4V. Feeding excess current into a protection diode can also trigger a phenomenon known as "SCR latchup" - when this happens the whole chip will start conducting heavily and heat up rapidly and burn out.The simplest fix is to place a 10k resistor in line with the GPS-TX to Arduino-RX connection. This limits the protection-diode current to about 150uA which it should be able to handle without cooking or risking latch-up.If you are lucky the GPS outputs are already current-limited and this explains why things still work - but this is a bad and expensive habit to get into - datasheets have a section at the top called "Absolute Maximum Ratings" - exceed these and all bets are off.