U18189@UICVM.UIC.EDU (Michael Sperberg-McQueen) (01/17/89)
Perhaps someone in this discussion can help me, at least by directing me to somewhere where I can get further information. I am using IBM TCP/IP software on a PS/2 to telnet in to an IBM 3081 running VM/SP over an Ethernet. To the VM system I appear as a 3270. The data clearly is passing over an eight-bit connection, because all the 190 printable code points of EBCDIC display as characters on my screen, not just the 94 characters of the old national EBCDICs. But the translation is unlike any I have seen documented anywhere; above all, it does not correspond, as far as I can tell, to the extended code pages for EBCDIC (code page 37 or code page 500) or ASCII (ISO 8859-1). We would like to provide ISO 8859-1 / EBCDIC CP 37 support for our users, so I would like to modify / customize / correct the translation. After some searching with DEBUG, I found an EBCDIC-ASCII translation table within TELNET.EXE (two, actually, which differ in some ways); by zapping the table with DEBUG I was able to get the desired translation between PS/2 extended ASCII (Code Page 850) and the U.S. Country Extended Code Page for EBCDIC (I believe this is Code Page 37, but I could be wrong). This (a) confirms that the PC software does the E-A conversion, and (b) seems a kind of awkward way of modifying the translate table. The same table also seems to affect ASCII-EBCDIC mapping (the caret sign changed its ASCII-to-EBCDIC mapping when I changed the table). My questions: 1 Is there any kind of support now in place for customizing the ASCII-EBCDIC translation? (I'm thinking of utilities like CONVXLAT EXEC on the VM side, or of the assembler macros for the Yale ASCII IUP for the Series/1.) Zapping the code with DEBUG is all right for me, but it's not something I feel good about recommending to users. Or even to the guy who is supposed to support the PC-based Telnet software. 2 Can anyone tell me what code pages were used to define the EBCDIC-ASCII translation for the "new" characters (ASCII characters higher than hex 80, EBCDIC characters undefined in the old 94-character code pages)? (That is, what is this translation table *doing*?) 3 Will future releases of the product support Code Page 37 or Code Page 500 (or any other of the Country Extended Code Pages)? We finally have a chance to see ASCII-EBCDIC conversion become reversible and involve no information loss -- it would be a real shame not to take advantage of the opportunity. At our site we finally managed, within the last year, to support the extended character sets on our Series/1s and 7171s. But we also need to support them on Ethernet connections. Any help you can give would be greatly appreciated. As I'm not a subscriber to this list, please reply directly to U18189@UICVM or U18189@UICVM.UIC.EDU -- many thanks. -Michael Sperberg-McQueen Systems University of Illinois at Chicago
jbvb@VAX.FTP.COM (James Van Bokkelen) (01/18/89)
It wouldn't surprise me if the UMD/IBM PC TN3270 has the same translation tables as Greg Minshall's ubiquitous Unix tn3270 (that's where we started, but they may also have started with one of IBM's own 3270 emulators...) In the Unix version, there was no provision for customizing the tables, unless you edited the source. The Unix version does have keyboard customization, but without an easy means of adding things to the translation tables, it isn't much good for accented characters. Regarding the keyboard issue: We have a re-mappable keyboard, which allows the user to define and re-define the codes returned by keystrokes (and combinations of keys). It isn't like the Unix version, though, and it doesn't allow anything like the Alt-keypad mechanism you mention. Regarding the translation table issue: I am in the final stages of testing fully loadable Ascii/EBCDIC translation tables for our TN3270. The files are binary, so local customization will be better done by fairly sophisticated people, and distributed with the rest of the package (e.g. by the local duplication operation that distributes copies under a PC/TCP Site License). This should show up in production by March or so. James VanBokkelen FTP Software Inc.
dzoey@TERMINUS.UMD.EDU (01/19/89)
> From: James Van Bokkelen <jbvb@vax.ftp.com> > It wouldn't surprise me if the UMD/IBM PC TN3270 has the same translation > tables as Greg Minshall's ubiquitous Unix tn3270 (that's where we started, > but they may also have started with one of IBM's own 3270 emulators...) I can't say for certain that the translation table isn't the same base as Minshall's, since I don't know where Greg obtained his, but our tn3270 did not evolve from Minshall's (we originally got the code from an IBMer). and modified the table to conform more with the 7171's used on campus (e.g. which square bracket to use etc.) > James VanBokkelen > FTP Software Inc. Joe Herman UMD PC/IP