Introduction to TI AM62x Boot Modes

The TI AM62x series supports multiple boot modes, allowing for various system configurations. These modes determine how the processor initializes and from where it retrieves the boot code.

1. Main Boot Modes of AM62x

1.1 MMCSD Boot Mode B6~B3=1000

In this mode, the AM62x processor boots from an SD card. The processor reads the bootloader and firmware from the SD card, allowing for easy updates and flexible deployment. This mode is very useful for developers, as most debugging is done using the SD card. Note that B9=Port refers to the MMC port; MMC0 is for eMMC and MMC1 is for SD card. It is crucial to choose the correct one based on the hardware.

1.2 UART Boot Mode B6~B3=0111

The UART (Universal Asynchronous Receiver-Transmitter) boot mode allows the processor to receive boot code through a serial connection. This mode is very useful for debugging and development purposes, enabling developers to load custom firmware or bootloaders via a terminal interface. When using UART boot, a series of messages will be printed for debugging, such as:

02000000011a0000616d3632780000000000000048534653010001000100010002a6000000000000d68ecb2c055dff11ade95bd927e837d2a53bc23b0a2800cebce4f106bcf309df2213912d77a157a8b7c2df40672a06a918034aa4c7d603e462481475225d49b8ad0bc40b0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005310c75ec7a01fe990c44e8f4b9e2c9289a756c9d30a7c6bafbdff5da9aacf39CC

Note that this is different from the “CCCC” printed by the AM335x.

1.3 eMMC Boot Mode B6~B3=1001

The eMMC (embedded MultiMediaCard) boot mode allows the AM62x to boot from eMMC storage. This is a common choice in embedded systems, as eMMC provides a reliable and fast storage solution. Similar to the SD boot mode, the processor loads the bootloader and firmware from the eMMC chip.

1.4 QSPI Boot Mode B6~B3=0001

In the QSPI (Quad Serial Peripheral Interface) boot mode, the AM62x processor boots from external QSPI flash memory. This mode is advantageous for applications requiring quick boot times and small firmware sizes. The processor retrieves the bootloader from the QSPI flash, enabling efficient startup.

1.5 Network Boot Mode (Ethernet) B6~B3=0100

The network boot mode allows the processor to load firmware over a network connection (such as TFTP). This mode is particularly useful for remote device management and updates, enabling developers to deploy new firmware without physical access to the device. It is suitable for situations requiring long-distance updates.

2. Boot Mode Selection

The boot mode can be selected through the processor's boot configuration pins. During development, developers should choose the appropriate boot mode based on specific application requirements and hardware configurations to ensure efficient system operation and flexibility. Understanding the boot modes of the TI AM62x processor is critical for developing and deploying embedded systems. By flexibly selecting boot modes, developers can optimize system performance and meet the needs of various application scenarios.

3. Boot Modes of Our AM62x Industrial Control Board

The Weathink WTC-AM62XXS industrial control board is designed based on the TI AM62x processor (including AM6231, AM6232, AM6234, AM6251, AM6252, AM6254), featuring a DIP switch that allows for multiple boot mode selections.

To boot from MMC1 (SD card) B9~B3=1001000

Set switches 7 and 4 to ON, and the others to OFF.

To boot from MMC0 (eMMC) B9~B3=0001000

Set switch 4 to ON, and the others to OFF.