Hello! I have build my own Breakout 50Pin board and also build power supply with LM317T which is 1.5A. I have also connected pins RX and TX to MAX232 chip. I measured that logic levels of that MAX 232 are 0-5V. So i was unable to communicate with GM862-GPS properly.
Now when i apply power to GM862, it self-starts operating without pressing the switch which is connected beetween ON/OFF pin and ground.
The status led flashes continuously if there is no SIM CARD present. If the SIM CARD is present, at the beging, led flashes couple times but then it is just on all the time.
My question is Could there be power supply problems because LT1528 in
hardware design guide has 3A and could i have damaged GM862 when i connected RX an TX pin to standard MAX232 which has 0-5V logic levels.
And also im interesting if i could set this logic 0-5V levels from standard MAX232 chip to GM862-GPS 0-2.8V levels?
Tnx!