Intel 80L186EB, 80L188EC, 80L186EC, 80C186EB, 80C188EB, 80L188EB Program Execution, GO Forever

iECM-86 COMMANDS

5.3.3Program Execution

These commands start and stop execution of user code. The commands provided are:

GO

GO FOREVER

GO FROM code_addr

GO FROM code_addr FOREVER

GO FROM code_addr TILL code_addr

GO FROM code_addr TILL code_addr OR code_addr

GO TILL code_addr

GO TILL code_addr OR code_addr

HALT

If a GO with breakpoint command is entered, the user code bytes at the breakpoints are saved and INT3s are substituted. When a breakpoint is reached, the user’s software stops before the instruction that caused the breakpoint and the iECM-86 software restores the original user code. Note that this differs from the operation of most ICE modules, which stop just after the instruction executes. A problem associated with stopping before the break instruction executes is that subsequent GO commands may run into the breakpoint before any user code is executed. The iECM-86 avoids this problem by skipping the setting of any breakpoints set on the instruction that the current PC points to. If this happens to remove the last breakpoint set, you are warned, but the GO still executes with no breakpoints enabled. If this happens, you can use the HALT command to stop the program.

None of the GO commands can be executed while the user’s code is already running; the HALT command cannot be executed if the user’s code is not running. The GO commands that set breakpoints use BR[0] and possibly BR[1]. Any break value already in one of these breakpoints is overwritten and destroyed by these GO commands. If possible, the user should reserve the first two breakpoints for use by the GO commands, and set the remaining breakpoints (if required) explicitly with the BR commands.

GO	This command starts execution of the user’s code using the current
	value of user’s program counter (PC) and the current breakpoint
	array.
GO FOREVER	This command clears the breakpoint array and starts execution at the
	current value of the user’s PC.

GO FROM code_addr This command loads the user’s PC with code_addr and starts execution of the user’s code using the current breakpoint array.

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