User's Manual

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Note d’étude / Technical document : URD1 – 5625.1 – 006 / 69796 Edition 03

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3.5.4 Partial V24 ( RX-TX) – connection MO300 - host

When using only RX/TX instead of the complete V24 link, we recommend following schematic :

We need DTR active (low electrical level), a loop DSR on DTR is sufficient because DSR is active (low

electrical level) once the MO300 is switched on.

We also need RTS active (low electrical level), a loop RTS on CTS is sufficient because CTS is active (low

electrical level) once the MO300 is switched on.

DCD and RI can stay not connected and floating.

Figure 23

Partial V24 connection (2 wires) between MO300 and host

3.6 UART 2

It is strongly recommended to let this interface externally accessible for Debug (e.g. access by 2 tests pads).

TXD2 and RXD2 can be used to get the software traces.

3.7 USB 2.0 OTG

The USB 2.0 interface is Full speed, then has a maximum rate of 12Mbit/s. It is On The Go capable then can be

in slave or Master mode depending on the connected equipment and the MO300 Version.

MO300 can only be in slave mode. Master mode and capability to switch between the two modes is only

available with the MO300E module.

In slave mode, the MO300 is answering to the customer application which is the Master of the communication.

RXD

TXD

RTS

CTS

MO300

DCD

DTR

DSR

GND

TXD

RXD

RTS

CTS

Host

DCD

DTR

DSR

GND