i have now GPRS shield v1.0 ( ?0.9b) and v1.2
on arduino uno, using arduino 1.0.1
and would like to use the RTC from the SIM 900 chip
on v1.2 is a battery holder ( for CR1220 3V )
say there MUST be a large capacitor, or a battery with diode or a rechargeable battery like XH414H-IV01E (Seiko)
in the v1.4 drawing i see a C6 connected parallel to battery holder / no diode/.
my board v1.2 i dont know.
testing AT commands get ERROR
must a battery be installed to get the RTC answer??
or does it only work together with time info from network??