Transfers - HP 9835A Programming Manual

Debugging
175
where {address} is the assembled location! for the break point desired. Following execution of
this statement, anytime the program execution reaches this address, it pauses. You may do any
keyboard operations necessary at this point, or you may start stepping the program, (if
IPAUSE ON has been executed), or you may resume execution using the
8
key. The
address must have been assembled before the IBREAK is executed.
If you were to execute -
then every time the fourth word past assembly label "Hook" is reached during execution, the
program execution pauses. If you were to execute -
then Hook is assumed to be a BASIC variable, and the result of the expression is assumed to be
an absolute address using whatever the value of Hook is when the statement is executed.
You can also specify the number of occurrences of reaching a break point before pausing
should come into effect. This is done by executing -
:1 1:::: F~:'
E::
I::::::
j ..
<
{address} : : {cou nter}
where {counter} is a numeric expression; any variables within {counter} are BASIC variables. A
pause occurs when {address} has been reached {counter} number of times. {counter} is reset
after each pause.
When a break point is reached and a pause is to be taken, the pause takes place
before
execution of the contents of that address.
Transfers
Instead of just pausing at a break point, it is possible to branch to a BASIC routine. The intent of
this facility is to give you access to BASIC's capabilities, particularly the printing and variable-
testing facilities, during your debugging efforts.
1 See "Buzzwords" in Chapter 1 for the definition of "assembled location".