flax@suadb.UUCP (Jonas Flygare) (10/01/87)
I just recently saw the program Diga!term (Or at least I think that what's it called) Quite impressed, BUT I have one question... As I understood it, one can load in terminal definition files and emulate new terminals, examples given were tek4010 and some others. Anyone know if it is possible to define your own terminal types, if so, is it difficult, and if not, will it be expensive to buy them? (I have a friend who really would like to have this HP series emulator, you see... And if I can convince him that you could do that on the Amiga (I don't have the time to write an emulator myself.. pop one level) the local user group would gain some more members.. :-)
jdow@gryphon.CTS.COM (Joanne Dow) (10/12/87)
In article <296@suadb.UUCP> flax@suadb.UUCP (Jonas Flygare) writes: > >I just recently saw the program Diga!term (Or at least I think that what's >it called) Quite impressed, BUT I have one question... As I understood it, >one can load in terminal definition files and emulate new terminals, >examples given were tek4010 and some others. Anyone know if it is possible to >define your own terminal types, if so, is it difficult, and if not, will >it be expensive to buy them? It is not a trivial task to generate any terminal emulator. (Ask papa, Keary Griffin, or Dillon, or . . .) It is probably easier for the Diga! package than others because all you have to generate is the emulation part. All the cleverness is around the outside. THe documentation for the emulation interface is available from Aegis, download from BIX, or I imagine any of many other systems. (I think CIS has a copy.) If you're clever doing emulations I bet you could cook one up comparatively easily. (And I bet many folks would be delighted to see some new terminal emulations posted for Diga!.) -- <@_@> BIX:jdow INTERNET:jdow@gryphon.CTS.COM UUCP:{akgua, hplabs!hp-sdd, sdcsvax, ihnp4, nosc}!crash!gryphon!jdow Remember - A bird in the hand often leaves a sticky deposit. Perhaps it was better you left it in the bush with the other one.
papa@uscacsc.UUCP (Marco Papa) (10/13/87)
Joanne Dow (jdow@gryphon.CTS.COM) writes: >In article <296@suadb.UUCP> flax@suadb.UUCP (Jonas Flygare) writes: > >>I just recently saw the program Diga!term (Or at least I think that what's >>it called) Quite impressed, BUT I have one question... As I understood it, >>one can load in terminal definition files and emulate new terminals, >>examples given were tek4010 and some others. Anyone know if it is possible to >>define your own terminal types, if so, is it difficult, and if not, will >>it be expensive to buy them? >It is not a trivial task to generate any terminal emulator. (Ask papa, Keary >Griffin, or Dillon, or . . .) It is probably easier for the Diga! package >than others because all you have to generate is the emulation part. All the >cleverness is around the outside. I agree. All terminals are quite the same: a giant switch statement that implements the state machine. The first one is usually the most difficult to write. My first one was a VT52. It took me a day. After that the H19 was only a couple of hours. Most of the time was spent with the font editor to duplicate the graphics fonts. The VT100 emulator I wrote for A-Talk took quite a lot more simply because the VT100 manual is incomplete and a LOT of things are undocumented, plus a "real" VT100 misbehaves and some bugs must be implemented to have VAX programs (like EDT) to work properly. That was of the order of a month (from 5PM till midnight). The Tek4010/4014 for A-Talk Plus was strangely quite easy, since the (very old) Tektronix documentation was quite good. Again quite a long time was spent trying to duplicate all the 4 Tek fonts (including a miniscule 5x6). It is in fact much simpler than a VT100, since the basic graphics call is to simply draw a line. In general it is easy to build an emulator that will do 90% of the real thing (that will take 10% of the time). The other 10% of the emulator will take 90% of the time (for example tek margin1-margin2, zoom mode, superbitmaps, Aegis Draw support, etc...). The Tek 4105, which we demonstrated at the Commodore Show-LA, though based on my Tek4014 is totally another beast, since much more graphics is involved: dithered patterns, hls-hvs-rgb conversions, panels, Graphtext (in 4 directions and 4 rotations), plus the fact that the switch table is not that straightforward since the end of an escape sequence is not fixed (commands have parameters of variable length). Speaking of the Commodore Show-LA, it was "unexpectedly" a big success. We finished our brochures after 2 hours, and passed saturday night photocopying. I saw LOTS of people leaving with an A500 (and a c64 emulator, really!! :). Also unexpected was the response to our pre-release of Digi-Weather, a custom version of A-Talk Plus, that permits downloading of Weather images, of the same type that one can see on the local evening news, from the Accu-Weather database. These include GOES satellite images that can be put in motion. All support full video up to 768x480. While our original market was small TV stations, we might end up also with a less expensive "amateur" package. Thanks a lot to Lauren Brown and Peter Baczor of Commodore and Michael Gerstein of UCLA for loaning us Amiga monitors (ours took a 5 feet jump during the recent LA earthquake and started smoking when powered on). About the Diga! emulations. Sure, they are now documented and one does not have to deal with the serial port, just the emulator. So the job is at least half done for you. In fact, we are thinking about generating a Tek4105 emulator for Diga!, but we'll have to wait until they put in support for color. -- Marco Papa Felsina Software