EK-TM4C123GXL

LAUNCHPAD TM4C123G EVAL BRD

The Tiva™ C Series TM4C123G LaunchPad Evaluation Board (EK-TM4C123GXL) is a low-cost evaluation platform for ARM® Cortex™-M4F-based microcontrollers. The Tiva C Series LaunchPad design highlights the TM4C123GH6PMI microcontroller USB 2.0 device interface, hibernation module, and motion control pulse-width modulator (MC PWM) module. The Tiva C Series LaunchPad also features programmable user buttons and an RGB LED for custom applications. The stackable headers of the Tiva C Series TM4C123G LaunchPad BoosterPack XL interface demonstrate how easy it is to expand the functionality of the Tiva C Series LaunchPad when interfacing to other peripherals on many existing BoosterPack add-on boards as well as future products. Figure 1-1 shows a photo of the Tiva C Series LaunchPad.

1.1 Kit Contents The Tiva C Series TM4C123G LaunchPad Evaluation Kit contains the following items: • Tiva C Series LaunchPad Evaluation Board (EK-TM4C123GXL) • On-board In-Circuit Debug Interface (ICDI) • USBmicro-B plug to USB-A plug cable • READMEFirst document

1.2 Using the Tiva C Series LaunchPad The recommended steps for using the Tiva C Series TM4C123G LaunchPad Evaluation Kit are:

1. Follow the README First document included in the kit. The README First document will help you get the Tiva C Series LaunchPad up and running in minutes. See the Tiva C Series LaunchPad web page for additional information to help you get started.

2. Experiment with LaunchPad BoosterPacks. A selection of Tiva C Series BoosterPacks and compatible MSP430™ BoosterPacks can be found at the TI MCU LaunchPad web page.

3. Take your first step toward developing an application with Project 0 using your preferred ARM tool-chain and the Tiva C Series TivaWare Peripheral Driver Library. Software applications are loaded using the on-board In-Circuit Debug Interface (ICDI). See Chapter 3, Software Development, for the programming procedure. The TivaWare for C Series Peripheral Driver Library Software Reference Manual contains specific information on software structure and function. For more information on Project 0, go to the Tiva C Series LaunchPad wiki page.

4. Customize and integrate the hardware to suit an end application. This user's manual is an important reference for understanding circuit operation and completing hardware modification. You can also view and download almost six hours of training material on configuring and using the LaunchPad. Visit the Tiva C Series LaunchPad Workshop for more information and tutorials.

1.3 Features Your Tiva C Series LaunchPad includes the following features:

• Tiva TM4C123GH6PMI microcontroller

• Motion control PWM

• USBmicro-A and micro-B connector for USB device, host, and on-the-go (OTG) connectivity

• RGBuser LED

• Twouser switches (application/wake)

• Available I/O brought out to headers on a 0.1-in (2.54-mm) grid

• On-board ICDI

• Switch-selectable power sources:

– ICDI– USBdevice

• Reset switch

• Preloaded RGB quickstart application

• Supported by TivaWare for C Series software including the USB library and the peripheral driver library

• Tiva C Series TM4C123G LaunchPad BoosterPack XL Interface, which features stackable headers to expand the capabilities of the Tiva C Series LaunchPad development platform

– For acomplete list of available BoosterPacks that can be used with the Tiva C Series LaunchPad, see the LaunchPad web page.

1.4 BoosterPacks The Tiva C Series LaunchPad provides an easy and inexpensive way to develop applications with the TM4C123GH6PM microcontroller. Tiva C Series BoosterPacks and MSP430 BoosterPacks expand the available peripherals and potential applications of the Tiva C Series LaunchPad. BoosterPacks can be used with the Tiva C Series LaunchPad or you can simply use the on-board TM4C123GH6PM microcontroller as its processor. See Chapter 2 for more information. Build your own BoosterPack and take advantage of Texas Instruments’ website to help promote it! From sharing a new idea or project, to designing, manufacturing, and selling your own BoosterPack kit, TI offers a variety of avenues for you to reach potential customers with your solutions.

1.5 Specifications Table 1-1 summarizes the specifications for the Tiva C Series LaunchPad.

The Tiva C Series LaunchPad includes a TM4C123GH6PM microcontroller and an integrated ICDI as well as a range of useful peripheral features (as the block diagram in Figure 2-1 shows). This chapter describes how these peripherals operate and interface to the microcontroller.

2.1 Functional Description

2.1.1 Microcontroller

The TM4C123GH6PM is a 32-bit ARM Cortex-M4-based microcontroller with 256-kB Flash memory, 32 kB SRAM, and 80-MHz operation; USB host, device, and OTG connectivity; a Hibernation module and PWM; and a wide range of other peripherals. See the TM4C123GH6PM microcontroller data sheet (literature number SPMS376) for complete device details.

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

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

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 Table 2-1.

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-Ω resistors. These resistors connect the USB ID and USB VBUS 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.

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.

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).

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.

Two quadrature encoder interfaces (QEI) are also available to provide motion control feedback. See the Headers and BoosterPacks section of this document for details about the availability of these signals on the BoosterPack interface.

2.1.4 User Switches and RGB User LED

The Tiva C Series LaunchPad comes with an RGB LED. This LED is used in the preloaded RGB quickstart application and can be configured for use in custom applications.

Two user buttons are included on the board. The user buttons are both used in the preloaded quickstart application to adjust the light spectrum of the RGB LED as well as go into and out of hibernation. The user buttons can be used for other purposes in the user’s custom application.

The evaluation board also has a green power LED. Table 2-2 shows how these features are connected to the pins on the microcontroller.

2.1.5 Headers and BoosterPacks

The two double rows of stackable headers are mapped to most of the GPIO pins of the TM4C123GH6PM microcontroller. These rows are labeled as connectors J1, J2, J3, and J4. Connectors J3 and J4 are located 0.1 in (2.54 mm) inside of the J1 and J2 connectors. All 40 header pins of the J1, J2, J3, and J4 connectors make up the Tiva C Series TM4C123G LaunchPad BoosterPack XL Interface. Table 2-3 through Table 2-6 show how these header pins are connected to the microcontroller pins and which GPIO functions can be selected.