Texas Instruments EK-TM4C123GXL 用户手册
Functional Description
Most of the microcontroller signals are routed to 0.1-in (2.54-mm) pitch headers. An internal multiplexer
allows different peripheral functions to be assigned to each of these GPIO pads. When adding external
circuitry, consider the additional load on the evaluation board power rails.
allows different peripheral functions to be assigned to each of these GPIO pads. When adding external
circuitry, consider the additional load on the evaluation board power rails.
The TM4C123GH6PM microcontroller is factory-programmed with a quickstart demo program. The
quickstart program resides in on-chip Flash memory and runs each time power is applied, unless the
quickstart application has been replaced with a user program.
quickstart program resides in on-chip Flash memory and runs each time power is applied, unless the
quickstart application has been replaced with a user program.
2.1.2 USB Connectivity
The EK-TM4C123GXL is designed and functions as a USB device without hardware modification. The
USB device signals are dedicated to USB functionality and are not shared with the BoosterPack headers.
The USB device signals are listed in
USB device signals are dedicated to USB functionality and are not shared with the BoosterPack headers.
The USB device signals are listed in
Table 2-1. USB Device Signals
GPIO Pin
Pin Function
USB Device
PD4
USB0DM
D–
PD5
USB0DP
D+
The TM4C123GH6PM target device is also capable of USB embedded host and on-the-go (OTG)
functions. OTG functionality can be enabled by populating R25 and R29 with 0-
functions. OTG functionality can be enabled by populating R25 and R29 with 0-
Ω
resistors. These
resistors connect the USB ID and USB V
BUS
signals to PB0 and PB1. When these resistors are populated,
PB0 and PB1 must remain in the respective USB pin mode configurations to prevent device damage. PB0
and PB1 are also present on the J1 BoosterPack header. Therefore, if R25 or R29 are populated, care
must be taken not to conflict these signals with BoosterPack signals.
and PB1 are also present on the J1 BoosterPack header. Therefore, if R25 or R29 are populated, care
must be taken not to conflict these signals with BoosterPack signals.
USB embedded host operation can be enabled in the same way for USB devices that are self-powered.
Providing power when acting as a USB host requires a BoosterPack with power switching and appropriate
connectors. All USB host signals are available on the BoosterPack interface except D+ and D–, which are
only available on the USB micro-A/-B connector and the two adjacent test points.
Providing power when acting as a USB host requires a BoosterPack with power switching and appropriate
connectors. All USB host signals are available on the BoosterPack interface except D+ and D–, which are
only available on the USB micro-A/-B connector and the two adjacent test points.
When connected as a USB device, the evaluation board can be powered from either the ICDI or the USB
Device connectors. The user can select the power source by moving the POWER SELECT switch (SW3)
to the Device position. See the Power Management schematic (appended to this document).
Device connectors. The user can select the power source by moving the POWER SELECT switch (SW3)
to the Device position. See the Power Management schematic (appended to this document).
2.1.3 Motion Control
The EK-TM4C123GXL includes the Tiva C-Series Motion Control PWM technology, featuring two PWM
modules capable of generating 16 PWM outputs. Each PWM module provides a great deal of flexibility
and can generate simple PWM signals—for example, those required by a simple charge pump—as well
as paired PWM signals with dead-band delays, such as those required by a half-H bridge driver. Three
generator blocks can also generate the full six channels of gate controls required by a 3-phase inverter
bridge.
modules capable of generating 16 PWM outputs. Each PWM module provides a great deal of flexibility
and can generate simple PWM signals—for example, those required by a simple charge pump—as well
as paired PWM signals with dead-band delays, such as those required by a half-H bridge driver. Three
generator blocks can also generate the full six channels of gate controls required by a 3-phase inverter
bridge.
Two quadrature encoder interfaces (QEI) are also available to provide motion control feedback. See the
section of this document for details about the availability of these signals on
the BoosterPack interface.
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Hardware Description
SPMU296 – April 2013
Copyright © 2013, Texas Instruments Incorporated