On power up, the EZ-KIT Lite board defaults to a baud rate of 115200 baud with 8
data bits, 1 stop bit, and no parity. If you want to change this rate change it after the
POST is complete use the
Settings -> Baud Rate
command from the debugger menu
bar. Note that setting the baud rate to a lower number can significantly slow the
boards response to all debug activities.
3.2.2.3 AD1819 Check/Initialization
On reset, the AD1819 begins transmitting the clock used to synchronize data transfers
over SPORT1.
Once this bit goes high, the AD1819 is ready for standard communication over
SPORT1. The POST then writes and verifies three patterns to an internal register in
the AD1819. If all three writes are verified, the connection is verified.
3.2.3 Monitor Program Operation
The monitor program runs on the EZ-KIT Lite board as part of the DSP executable and pro-
vides the ability to download, debug, and run user programs. The Vi+ debugger
is the interface for the monitor and using the EZ-KIT Lite as a target with the debugger lets
you operate the board remotely.
There are three main components of the monitor program:
•
Halt loop
•
UART ISR
•
Command Processing Kernel
The monitor program idles in the Halt loop when it is not running user code. While there,
you can read/write memory, read/write registers, download programs, set breakpoints,
change the UART’s baud rate, modify the AD1819 configuration, and single step through
code. To enter the halt loop from your code, you must halt user code—either with a
breakpoint or a halt instruction. At this point, the halt loop polls the UART. With every
character received from the UART, the command processing kernel verifies whether a full
command has been received. If a command has been received, the kernel processes the
command; otherwise control is returned to the halt loop to wait for more characters. The
only method of executing your code once the halt loop has been entered is to send a Run or
Single Step command in the debugger.
The UART ISR is entered when user code is running, but the host is still interacting with
the board. As the host sends bytes, the UART ISR takes the data stream from the UART,
and builds the command. As with the halt loop, each character received is passed to the
command processing kernel. Unlike the halt loop, the monitor returns to the user code
immediately after the interrupt is serviced.
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