Texas Instruments 990 Operation Manual page 46

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The individual debug commands are described in paragraph 3.4.12 through 3.4.32.
3.4.1.4 PROM/ROM Process Control Command Codes. PROM/ROM Process Control commands
are identified by two-letter mnemonic codes and may be followed by one or more parameters.
This group of commands include:
• PROM· Programmer Standard (PS)
•
PROM Programmer (PP)
• Perform BNPF Operation(DB)
• Perform HIGH/LOW Operation (HL)·
The individual process control commands are described in Section VII,· VIII and IX.
3.4.1.5 Command Parameters. A keyboard command mnemonic code may be followed by one
or more parameters. The list of parameters is separated from the command code by one or more
blanks or a comma.
The parameters in the list are delimited by commas or by strings of one or more blanks. Each
parameter may be a hexadecimal number of one to four hexadecimal digits or a string of
alphanumeric characters.
3.4.1.6 Entry of Commands. Keyboard commands may be entered whenever the software
system is in command mode. In this mode, a period (.) is printed as the first character on a new
line. Depending on the command executed, the software system mayor may not return to
command mode. The monitor requests another command by printing another period (.) at the
beginning of a line. No program executing under the monitor uses a period in this manner to
request user input.
3.4.1.7 Command String Processor. The command string processor parses command input
strings, given command definition tables. It validates parameter values and converts those
representing hexadecimal numbers to binary. It also indicates the existence and position of all
null parameters.
The command string processor can parse up to eight parameters. It passes control to the
appropriate command processor ·after it has recognized a syntactically correct command.
3.4.1.8 Processing of Commands. It is helpful to the user to understand how the commands are
executed. The command processor handles commands in the following ways.
• A command string is aborted and data is cleared from the buffers on any error.
• The command is checked against a predefined list of acceptable commands.
• The command and any parameters are validated immediately after the appropriate
terminator is processed for that parameter (or command). If an error is detected, the
entire input is discarded.
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