SPRUJ63A September 2022 – October 2023
The boot mode for the EVM is defined by either a bank of switches SW2 and SW3 or by the I2C buffer (U96) connected to the test automation connector (J38). All the boot mode pins have a weak pull-down resistor and a switch capable of connecting to a strong pull up resistor. Switch set to “ON” corresponds to logic “HIGH” while “OFF” corresponds to logic “LOW”.
For a full description of all AM64x SoC supported bootmodes, see the AM64x Sitara™ Processors Data Manual and AM64x Processors Silicon Revision 1.0 Texas Instruments Families of Products Technical Reference Manual.
The following boot modes are supported by EVM (and subject to change):
The BOOTMODE pins provide means to select the boot mode before the device is powered up. The pins are divided into the following categories:
Bit 15 | Bit 14 | Bit 13 | Bit 12 | Bit 11 | Bit 10 | Bit 9 | Bit 8 | Bit 7 | Bit 6 | Bit 5 | Bit 4 | Bit 3 | Bit 2 | Bit 1 | Bit 0 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
RSVD | RSVD | Backup Boot Mode Config | Backup Boot Mode | Primary Boot Mode Config | Primary Boot Mode | PLL Config |
BOOTMODE[2:0] - Denote system clock frequency for PLL configuration. By default, these bits are set for 25 MHz.
SW2.3 | SW2.2 | SW2.1 | PLL REF CLK (MHz) |
---|---|---|---|
off | off | off | 19.2 |
off | off | on | 20 |
off | on | off | 24 |
off | on | on | 25 |
on | off | off | 26 |
on | off | on | 27 |
on | on | off | RSVD |
on | on | on | RSVD |
BOOTMODE[6:3] - This provides primary boot mode configuration to select the requested boot mode after POR, that is, the peripheral/memory to boot from.
SW2.7 | SW2.6 | SW2.5 | SW2.4 | Primary Boot Device Selected |
---|---|---|---|---|
off | off | off | off | RSVD |
off | off | off | on | OSPI |
off | off | on | off | QSPI |
off | off | on | on | SPI |
off | on | off | off | RSVD |
off | on | off | on | RSVD |
off | on | on | off | I2C |
off | on | on | on | UART |
on | off | off | off | MMC/SD Card |
on | off | off | on | eMMC |
on | off | on | off | USB |
on | off | on | on | GPMC NAND |
on | on | off | off | GPMC NOR |
on | on | off | on | PCIe |
on | on | on | off | xSPI |
on | on | on | on | No-boot / Dev-boot |
BOOTMODE[9:7] - These pins provide optional settings and are used in conjunction with the primary boot device selected. For more details, see the device-specific TRM.
SW3.2 | SW3.1 | SW2.8 | Primary Boot Device |
---|---|---|---|
RSVD | RSVD | RSVD | RSVD |
RSVD | Iclk | Csel | OSPI |
RSVD | Iclk | Csel | QSPI |
RSVD | Mode | Csel | SPI |
RSVD | RSVD | RSVD | RSVD |
RSVD | RSVD | RSVD | RSVD |
Bus Reset | Don't Care | Addr | I2C |
RSVD | RSVD | RSVD | UART |
Port | RSVD | Fs/raw | MMC / SD Card |
RSVD | RSVD | RSVD | eMMC |
Core Volt | Mode | Lane Swap | USB |
RSVD | RSVD | RSVD | GPMC NAND |
RSVD | RSVD | RSVD | GPMC NOR |
RSVD | RSVD | RSVD | PCIe |
SFDP | Read Cmd | Mode | xSPI |
RSVD | RSVD | RSVD | No-boot / Dev-boot |
BOOTMODE[12:10] - Select the backup boot mode, that is, the peripheral/memory to boot from, if primary boot device failed.
SW3.2 | SW3.1 | SW2.8 | Backup Boot Device Selected |
---|---|---|---|
off | off | off | None (No backup mode) |
off | off | on | USB |
off | on | off | RSVD |
off | on | on | UART |
on | off | off | RSVD |
on | off | on | MMC/SD |
on | on | off | SPI |
on | on | on | I2C |
BOOTMODE[13] - These pins provide optional settings and are used in conjunction with the backup boot device devices. For more details on bit details, see the device-specific TRM. When on, switches SW3.6 sets 1 and, when off, sets 0.
SW3.6 | Boot Device |
---|---|
RSVD | None |
Mode | USB |
RSVD | RSVD |
RSVD | UART |
RSVD | RSVD |
Port | MMC/SD |
RSVD | SPI |
RSVD | I2C |
BOOTMODE[14:15] - Reserved.