LAUNCHXL-F28027 Datasheet, PDF (7/15 Pages) Texas Instruments – LAUNCHXL-F28027 C2000 Piccolo LaunchPad

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Hardware Configuration
4.1 Power Domain
The C2000 LaunchPad has two separate power domains for the purpose of allowing JTAG isolation.
Jumpers JP1, JP2, and JP3 configure whether the USB power is passed to the target device.
Jumper
JP1
JP2
JP3
Power Domain
3.3 V
Ground
5V
4.2 Serial Connectivity
The LAUNCHXL-F28027 has a USB to UART adapter built in. This makes it easy to print debug
information back to the host PC even in isolated environments. However, in some cases the user may
wish to connect the Piccolo SCI peripheral (C2000 UART peripheral) to a BoosterPack or other hardware
via the header pins. If the SCI pins are connected to both the header pins, the XDS100 UART channel
contention would exist and the pins would not be driven to the correct voltage levels. To solve this issue
we have included a switch to allow the user to disconnect the Piccolo serial pins from the XDS100 UART
connection. When S4 is in the up position, the Piccolo device's SCI is connected to the XDS100 and you
are able to receive and send serial information from or to the board. When S4 is in the down position, the
Piccolo device's SCI is disconnected from the XDS100 and BoosterPacks, which use serial
communication, and can communicate with the Piccolo device.
4.3 Boot Mode Selection
The LaunchPad's F28027 device includes a boot ROM that performs some basic start-up checks and
allows for the device to boot in many different ways. Most users will either want to perform an emulation
boot or a boot to flash (if they are running the application standalone). S1 has been provided to allow
users to easily configure the pins that the bootROM checks to make this decision. The switches on S1
correspond to:
Switch
1
2
3
Function
GPIO34
GPIO37
TRSTn
Keep in mind that the debugger does not connect if the device is not in the emulation boot mode (TRST
switch in the up position). More information about boot mode selection can be found in the
TMS320x2802x Piccolo Boot ROM Reference Guide (SPRUFN6).
4.4 Connecting a Crystal
Although the Piccolo device present on the LAUNCHXL-F28027 has an internal oscillator — and for most
applications this is sufficient — the LaunchPad offers a footprint for surface mount or through-hole HC-49
crystals for users who require a more precise clock. If you wish to use an external crystal, solder the
crystal to the Q1/Q2 footprint and appropriate load capacitors to the C3 and C4 footprints. You also need
to configure the device to use the external oscillator in software.
4.5 Connecting a Satellite Board
The C2000 LaunchPad is the perfect experimenter board to start hardware development with the F2802x
devices. Connectors J1, J2, J5, and J6 and the power supply at J3 are aligned in a 0.1-in (2.54-mm) grid
to allow an easy and inexpensive development of a breadboard extension module. These satellite boards
can access all of the GPIO and analog signals. The alignment of the connectors and the pin out can be
found in Section 5.
SPRUHH2 – July 2012
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LAUNCHXL-F28027 C2000 Piccolo LaunchPad Experimenter Kit
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Copyright © 2012, Texas Instruments Incorporated