Atmel AT43DK325, Руководство пользователя

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Hardware Description
AT43DK325 USB Controller Dev. Kit User Guide 3-3
3430B–USB–3/04
PF3 also has an alternate function as an input capture pin for a Timer/Counter1 feature.
Note that PF0 is not available for general purpose I/O.
3.12 Solid State
Power Switch U3
This switch is used to support ganged power switching. This board uses Micrel
MIC2026-2BM.
3.13 Header GND TP1
and TP2
This pin provides ground voltage reference.
3.14 2x2 Header JP9
The Development Board supports ganged power switching to the available USB ports
using a Micrel MIC2026-2BM solid state power switch. The PDX0 and PDX1 must be
connected to this switch by installing a jumper to this header. By default, two jumpers
are installed at this header. If the system is not used, PDX0 and PDX1 are available as
general purpose I/Os.
3.15 Header JH1
This pin is also used as an input capture pin for the Timer/Counter1 feature.
3.16 USB External
Downstream Port
J2, J3, J4, and J5
Connectors
These connectors provide downstream connection to USB devices. There are 5 down-
stream ports. Port 1 is permanently used by the embedded function and is not visible.
On this board, J2, J3, J4 and J5 correspond to embedded USB hub ports 5, 4, 3 and 2
respectively. The power source of these ports is controlled by power switch U3.
3.17 USB Upstream
Port J1
Connector
This connector provides upstream connection to the host or to another hub.
3.18 Programmable
Microcontroller
U2
This board comes with the AT43USB325E microcontroller.
3.19 2x2 Header JP10
Pin 1 on this header is connected to both VSS1 and VSS2 of U2 (microcontroller), while
pin 2 and pin 4 are connected to the TEST and SYSCLK pins of U2 respectively. No
connection to pin 3 of this header.
3.20 Two-wire Serial
EEPROM U5
This board includes a two-wire Serial EEPROM for extra memory. The device plugged
into this socket is the AT24C02A. Please refer to the ATC024A datasheet for more infor-
mation about this device.