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HP71B: two questions - Vieira, Luiz C. (Brazil) - 07-19-2003

Hi, HP71B users;

my turn to ask questions.

I received one e-message mentioning the HP71B's ROM version. How can I know which version is mine? Serial # or some specific command?

I remember that BASIC variables are all set to "0" (empty?) and all definable variables for an specific BASIC environment exist anytime a program "call" their contents. This is not the same with C, where variables not "declared" in a program are taken as "error" if called. Anyway, based on what I saw so far, used variables in the HP71B consume memory space. Is there a way to list varable names already used somehow?

Thanks for any help.

Luiz (Brazil)

Edited: 19 July 2003, 5:41 p.m.


Re: HP71B: two questions - Emmanuel, France - 07-19-2003

VER$ should give you the version of your HP-71B and plugged ROMs. If I remember well...
Yours.



Re: HP71B: two questions - Sean McNamee - 07-19-2003

...and my turn to pay you back ;)
Yes, VER$ gives version info, and
DELETE ALL deletes the space used by variables.
Also, you can DELETE specific vars by name.


Re: HP71B: two questions - Vieira, Luiz C. (Brazil) - 07-19-2003

Hi, Sean;

thank you for the information. I read that DESTROY names and DESTROY ALL would "erase" variable contents. I was not know about DELETE being used the same way.

Now, is there a way to know which variables have their contents changed before "erasing" (deleting, destroying) them? I thought about listing their names. Is it possible?

Thanks again.

Luiz (Brazil)


Thanks Emmanuel and Sean - Vieira, Luiz C. (Brazil) - 07-19-2003

Hi, Emmanuel;

thank you. As Sean confirms your answer, you actualy remembered it well.

Best regards.

Luiz (Brazil)


Re: HP71B: two questions - oops - Sean - 07-19-2003

Sorry - I meant DESTROY. Not DELETE. I tend to mix both of those as well as PURGE up....
I really have no idea about listing variables, let me find my manual and take a look.... (will post results)


Re: HP71B: two questions - Victor Koechli - 07-19-2003

DESTROY <var> can be used to free the memory used by individual variables, and DESTROY ALL will delete all allocated variables in the current environment.

However, I have not found an obvious way to list the variables currently allocated. You would probably have to consult the Software IDS to find out where this information is stored, and peek it from the HP 71's allocation tables.

Cheers, Victor


That's what I was affraid of... - Vieira, Luiz C. (Brazil) - 07-19-2003

Hello, Victor;

I was affraid I'd have to "peek" RAM positions in order to seek for variables. I'm not aware of how is data organized in the HP71's RAM, I believe I'll find this information in the Internal Specs documents, as you mentioned.

I'd be delving into this subject with more "energy" if I had an HP71B, say, eighteen years ago, when I was actualy programming and working with assembly code. But I'll find the time to go further somehow.

Thanks a lot.

Luiz (Brazil)

Edited: 19 July 2003, 9:32 p.m.