Datasheet

69
SAM9G45 [DATASHEET]
Atmel-6438O-ATARM-SAM9G45-Datasheet_08-Dec-15
10.5 SAM-BA Monitor
If no valid code has been found in NVM during the NVM bootloader sequence, the SAM-BA Monitor program is
launched.
The SAM-BA Monitor principle is to:
 Initialize DBGU and USB
 Check if USB Device enumeration has occurred.
 Check if characters have been received on the DBGU.
 Once the communication interface is identified, the application runs in an infinite loop waiting for
different commands as listed in Table 10-5 on page 70.
Figure 10-8. SAM-BA Monitor Diagram
Character(s) received
on DBGU ?
Run monitor
Wait for command
on the USB link
Run monitor
Wait for command
on the DBGU link
USB Enumeration
Successful ?
Yes Yes
No
No
Init DBGU and USB
No valid code in NVM