User's Manual

T-0000-0004-V2.1: Using Mozart II
T-0000-0004-V2.1: Using Mozart II Page: 13 / 24
R9
75R
R8
75R
R7
75R
C71
1n 2kV
ETH_VCC
R6
49R9
RXN
TXN
RXP
DGND
ETHERNET
DGND
R5
49R9
R4
49R9
R3
49R9
C7
100n 16V
TXP
TXP
TXN
RXP
ETH_VCC
RXN
C5
100n 16V
C6
100n 16V
C8
1n 2kV
J1
RJ45 Conn
TX+
1
TX-
2
RX+
3
RX-
6
NC4
8
NC3
7
GND
9
GND
10
NC1
4
NC2
5
U1 HST-0041SR
TD+
1
Com_TD
2
TD-
3
RD+
6
Com_RD
7
RD-
8
RX-
9
Com_RX
10
RX+
11
TX-
14
Com_TX
15
TX+
16
NC1
4
NC2
5
NC3
12
NC4
13
R10
75R
10 Dealing with USB
The module has an external connection for the D+/D- differential pair of USB data. In order for the
signals to be kept in proper condition, care must be taken for the lines to be routed with impedance
matching (90 ohm differential) and with minimal length.
Powering for the external USB device is left to the device designer. It is recommended that the USB
power supply is able to provide 500mA; the module does not provide any kind of negotiation for power
supply, however an active high USB_OC pin can be used to signal an over current condition. Actual
current limiting needs to be done by the external electronics; this is a mandatory feature since external
devices may fail and break the internals of the device.
It is up to the device designer to select the protection system – mostly following cost reasons.
Specialized chips are available from many manufacturers (Sipex, Micrel …) that allow power control
and overcurrent reporting; or Polyswitch ® fuses can be used as the simplest protection system.
USB lines must follow the reference schematic with filtering parts located as close as possible to the
connector.
11 Dealing with Infrared Remote Controls
The module features a direct entry for demodulated infrared signals using the Philips RC5 code. The
signal expected from the external demodulator (such as Vishay TSOPxx38 series) must be inverted
(those demodulators have an open-drain output). With this part, the connection is direct. An external
pullup is not required, however power supply decoupling as recommended in device datasheet shall
be put in place.
As for the application button mapping, the kind of remote control used greatly depends on the
application software – and customer decision regarding the type of features that will be controllable
through the remote control. The most basic application would be volume control and maybe preset
control.
12 Display / LCM support
128x64 SPI monochrome (RT3050, 32MB RAM)
QVGA SPI COLOR TFT (RT3052 64MB RAM)