User's Manual

GE/GC864-QUAD V2 and GE864-GPS Hardware User Guide
1vv0300915 Rev.2 – 2011-06-15
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights
Reserved. Page 62 of 97
By convention the driver is the level translator from the
0/+3V UART level to the RS232 level, while the receiver is the
translator from RS232 level to 0/+3V UART.
In order to translate the whole set of control lines of the
UART you will need:
• 5 driver
• 3 receiver
NOTE:
The digital input lines working at 2.8V CMOS have an absolute
maximum input voltage of 3.0V; therefore the level translator
IC shall not be powered by the +3.8V supply of the module.
Instead, it must be powered from a +2.7V / +2.9V (dedicated)
power supply.
This is because in this way the level translator IC outputs on
the module side (i.e. GE/GC 864 inputs) will work at +3.8V
interface levels, damaging the module inputs.
NOTE:
In order to be able to do in circuit reprogramming of the
GE/GC 864 firmware, the serial port on the Telit GE/GC 864
shall be available for translation into RS232 and either it's
controlling device shall be placed into tristate, disconnected
or as a gateway for the serial data when module reprogramming
occurs.
Only RXD, TXD, GND and the On/off module turn on pad are
required to the reprogramming of the module, the other lines
are unused.
All applicator shall include in their design such a way of
reprogramming the GE/GC 864.