Texas Instruments 990 Operation Manual page 21

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945255-9701
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Instruction trace
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PROM Programmer
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BNPF format dump
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HIGH/LOW format dump
Overlays are loaded in the transient area of the debug monitor's memory space. Since the PROM
programmer is too large to fit in the transient area, part of it is loaded into the highest-
numbered address locations of user memory. The overlay-resident commands are used exactly
like normal commands once the overlay is loaded into the transient area. Attempts to invoke
commands which are not resident will generate error messages.
1.4.3.1 Linking Loader. The linking loader, PX9LAL, loads program modules into memory,
links the modules as required, and returns control to the monitor after all modules have been
loaded. The loaded program modules are object modules produced by one of these assemblers:
• One-Pass Assembler (PX9ASM)
• SDSMAC, the macro-assembler in the 990/10 Program Development System.
• Cross Assembler, which allows the user to assemble code for the 990 Family of
computers on an IBM System 360/370 or on certain international timesharing services.
1.4.3.2 Absolute Dump/Absolute Load. The Absolute Dump/Absolute Load overlay routine
provides two functions: it saves a program or data space in memory by writing that program or
data onto 733 ASR cassette tape in compressed absolute data format, and it loads object code
that has been stored in compressed absolute data format. The saved memory data sequence is
stored in compressed absolute data format, and can be reloaded using either the absolute loader
or the upfront loader, both invoked by monitor keyboard commands. The absolute dump can
also be used to save an entire memory data sequence complete with the current debug
parameters in the data sequence. The memory data sequence can then be reloaded from the start
and the debugging continued as if it were never interrupted.
1.4.3.3 Instruction Trace. The instruction trace feature allows the user to monitor the contents
of internal data sequences and analyze the ongoing progress of an executing program. The user
can specify breakpoints and snapshots for interpreting the progress of his program.
1.4.3.4 PROM Programmer. The PROM Programmer software package provides flexible control
of the PROM programming process through the use of PX9MTP operator commands. The PROM
programmer commands inform the control software of memory bounds, PROM characteristics,
and mapping parameters. Additional operator commands allow the use of standardized control
information for frequently used programming functions. With PROM programmer commands, the
user is able to program PROMs and verify the contents of a PROM or ROM circuit.
The PROM programmer requires that the debugged software routine to be transferred to a
PROM be resident in memory. The software module selects data from memory and transfers it
with other interface data to the PROM Programming Module. The hardware module stores the
received data in the PROM as directed by the command.
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Digital Systems Division