Intel 80L188EC Benutzerhandbuch

5-5

Commands that control program execution allow you to reset the processor, set execution break-
points, start execution, stop execution, step, and super step. The commands are grouped by their
major functions for the sake of discussion. 

The processor can be reset by executing the following iECM-86 command:

This command physically resets the processor by setting the RISM_DATA register to
0XXXX0001 and issuing a MONITOR_ESC RISM command, which causes the target to
perform a JMP FFFF:0000H instruction.

This command resets the entire iECM-86 system, including the target. It operates by bringing the
DCD line of the serial port low. This, with appropriate circuitry in the target system, resets the
target processor. During this process, the iECM-86 software must wait about one second to allow
the main board to complete its initialization routines. The iECM-86 warns of this time delay and
then ignores the user until it expires. Any user code in the Flash must be reloaded after this
command.

iECM-86 provides sixteen program execution breakpoints. If a given breakpoint is inactive, it is
set to zero; if it is active, it is set to the address of the first byte of an instruction. Breakpoints set
to addresses that are not the first byte of an instruction cause unpredictable errors in the execution
of the user’s code. When execution is started, iECM-86 saves the user code byte at any active
breakpoint and substitutes an INT3 instruction for that byte. Executing an INT3 instruction
causes the iECM-86 to restore the user code bytes where the INT instructions were substituted
and then decrement the user’s program counter so that it points to the original instruction. The
user’s program appears to stop execution immediately before executing the instruction with a
breakpoint set on it. All INT instructions are removed from the user’s code and the original code
is restored.