EGS5 Hardware Interface Description
3.12 USB Interface
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EGS5_HD_v02.004
Page 56 of 123
2012-02-09
Confidential / Released
3.12
USB Interface
EGS5 supports a USB 2.0 Full Speed (12Mbit/s) device interface. The USB interface is primar-
ily intended for use as command and data interface and for downloading firmware. The USB I/
O-lines are capable of driving the signal at min 3.0V. They are 5V I/O compliant.
The USB port has different functions depending on whether or not Java is running. Under Java,
the lines may be used for debugging purposes (see
for further detail). If Java is not used,
the USB interface is available as a command and data interface and for downloading firmware.
The USB host is responsible for supplying, across the VUSB_IN line, power to the module’s
USB interface, but not to other EGS5 interfaces. This is because EGS5 is designed as a self-
powered device compliant with the “Universal Serial Bus Specification Revision 2.0”
3
.
Figure 18:
USB circuit
To properly connect the module’s USB interface to the host a USB 2.0 compatible connector
is required. For more information on how to install a USB modem driver and on how to integrate
USB into EGS5 applications see
. This Application Note also lists a selection of USB 2.0
hubs the module has been tested to operate with.
Because its USB stack is based on the Communication Device Class Abstract Control Model
specification (CDC ACM v1.1), the module is integrated as a USB modem device with a virtual
COM port - supporting most of the control and status lines an RS-232 serial interface would.
Note that communication over the USB interface is only possible if the virtual DTR line on the
virtual COM port is active.
3.
The specification is ready for download on
