Codepage switching

[Anonymous]

couldnt you just do

Code:

SHELL "MODE CON whatever code"

?

is it necessary to reboot?

[na_th_an]

Yeah, it is. You need to load COUNTRY.SYS in CONFIG.SYS specifying some stuff.

Plasma's sollution seems the better by now. I can provide you a textmode font editor and QB code to load the font and activate it in textmode.

[Moneo]

Couldn't you just redefine all the characters to those of the desired code page...?

Nathan,
You say that Plasma's solution is the better. However, if the friends who are going to run Alun's programs have several different codepages, Alun would have to to create several different versions of his programs with the redefined characters for each particular codepage on his friends' machines.

If his friends ALL use the same codepage, then this might be a solution since then Alun would only need 2 versions of his programs. If they don't all use the same codepage, making several versions could become a pain in the butt, especially when Alun would need to change the codepage on his machine in order to test each different version.

If Alun is going to heve to get in and modify his programs more than once to do what Plasma says, then I refer back to my previous idea (post of 24-Dec) where I suggested using a character conversion file. In this manner, If a new firend with a new codepage wants to use Alun's programs, then he only sets up a conversion file for the corresponding characters that this new friend needs to use.

However, I still content that the best way to go is a standalone bootable diskette with Alun's programs and his required codepage setup. This way he doesn't have to modify his programs at all, plus all the testing can be done on his own machine.

Regarding the bootable diskette solution, we haven't heard from Alun on the following important issues:
1) How many programs are we talking about?
2) Do the executables (including any utilities invoked) fit on one diskette?
3) Do the programs need to write any large files; that is, would these exceed the capacity of the diskette?
4) Would running form the A: drive hamper the performance of the programs?
*****

[Plasma]

Huh? He only has to create one version. By "redefine" I mean redefine the graphics of the actual characters, not remap the characters.

He wants the extended characters of codepage 437, so all he has to do is load up that codepage and dump the font data to a file. Then his program can load that data and redefine the extended characters at runtime. (He can also restore the original extended characters by saving them before he redefines them...)

[Moneo]

Plasma,
I don't quite understand how to do what you're saying, but the idea sounds good. Let's see what Alun thinks.
*****

[na_th_an]

Moneo, the text mode character set can be changed. That's what MODE does, mainly. A text mode font set takes 4 Kb. You can set a new one loading a new set of characters somewhere in memory and calling one function in the interrupt 10h. I have QB code to do that.

[Moneo]

Nathan, Ok, let's see if Alun wants and knows how to do this. We seem to have lost him 3-4 days ago.
*****

[Alun]

Hi fellas', no you haven't lost me it's just I have had a Christmas vacation away from the PC. Nathan seems possibly close to solving my problem. But does this mean the PC has to be booted up with two codepages and the QB program then switches between the two, or does the QB program load the codepage and then allows switching. The former would still give a problem, the latter would be ideal.

Belated complements of the season to you all, Alun.

[na_th_an]

Nope. You don't have to boot. Just load the new font, and activate it using a single interrupt call.

[Alun]

Nathan, sounds great, tell me more. Alun