How to Interface Max 232 to GM47

[ranadala]

i use max 232 to communicate with gsm module GM47.

There is level different between them. max 232 serve 0-5V and GM 47 serve 0-3V.

First i use level shifter using bjt shifter to step-down from max232 to GM47
and bjt shifter to step-up from GM47 to max232 but fail in hyperterminal looping test.
Then i use buffer uln 2803 to step-down but direct connection to step-up because
level 3V is still valid for max232, but then hyperterminal test is still fail.

Pease help me

 

[bobcat1]

Hi

Use Max3232 insted it's working with 3.3V insted of 5V

All the best

Bobi