This section details what boot
configurations are available and how to configure them. This device supports from 0
boot mode select pins up to 3 boot mode select pins as well as from 1 configured
boot mode up to 8 configured boot modes.
To change and configure the device
from the default settings to custom settings for your application, use the following
process:
- Determine all the various ways you want application to be able
to boot. (For example: Primary boot option of Flash boot for your main
application, secondary boot option of CAN boot for firmware updates, tertiary
boot option of SCI boot for debugging, etc)
- Based on the number of boot modes needed, determine how many
boot mode select pins (BMSPs) are required to select between your selected boot
modes. (For example: 2 BMSPs are required to select between 3 boot mode
options)
- Assign the required BMSPs to a physical GPIO pin. (For example,
BMSP0 to GPIO10, BMSP1 to GPIO51, and BMSP2 left as default which is disabled).
Refer to Section 7.10.1.1 for all the details on performing these configurations.
- Assign the determined boot mode definitions to indexes in your
custom boot table that correlate to the decoded value of the BMSPs. For example,
BOOTDEF0=Boot to Flash, BOOTDEF1=CAN Boot, BOOTDEF2=SCI Boot; all other BOOTDEFx
are left as default/nothing). Refer to Section 7.10.1.2 for all the details on setting up and configuring the custom boot mode
table.
Additionally, the Boot Mode Example Use
Cases section of the TMS320F28P55x Real-Time
Microcontrollers Technical Reference Manual provides some example
use cases on how to configure the BMSPs and custom boot tables.
Note: The CAN boot mode turns on the
XTAL. Be sure an XTAL is installed in the application before using CAN boot
mode.