Programming Embedded Systems in C and C++

Emulators 35

The tdr command is actually a batch file that invokes two other commands. The

first tells the on-board debug monitor which version of Turbo Debugger you will

be using, and the second actually invokes it. Both of these commands need to be

issued each time you want to start a remote debugging session with the Arcom

board. The tdr.bat batch file exists solely to combine them into a single command

line. Again we use the relocatable version of the program because we will be

downloading the program into RAM and executing it from there.

The debugger startup options –rp1 and –rs3 establish the parameters for the com-

munications link to the debug monitor. –rp1 means “remote-port=1” (COM1) and

–rs3 means “remote-speed=3” (38,400 baud). These are the parameters required to

communicate with Arcom’s debug monitor. After establishing a connection to the

debug monitor, Turbo Debugger should start running. If it does not, there might

be a problem with the serial link. Compare your setup of the link to the one in the

SourceVIEW user’s manual.

Once you’re in Turbo Debugger, you will see a dialog box that says: “Program out

of date on remote, send over link?” When you select “Yes,” the contents of the file

blink.exe will be downloaded to the target RAM. The debugger will then set an ini-

tial breakpoint at main and instruct the debug monitor to execute the program

until that point is reached. So the ...