Jterm BBC Comms Software
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Reviewed by Martin Wilson
Although I have an A3010 which is more than satisfactory for Comms use I
decided I would try out some BBS's with my Master Turbo. There wasn't really
a valid reason for doing this apart from curiosity.
First of all there were two problems before I could get going, the first
being the cable. I didn't have one to link the Master to my modem. I was
pretty sure I had a 5 pin domino to 25 way lead somewhere but a quick search
couldn't find it. The only one I had found was a 5pin domino to 5pin domino
for connecting two Beebs together. Not a lot of use to me when I only have
one BBC with a serial port.
The A3010 has a standard 9pin serial port and I have two PC type modem
cables one of which is a long version with just the 9pin connector and
another has both 9pin and 25pin on the same cable. Both cables end with the
normal 25way connector for the modem.
So I just had to make up a new 5pin domino to 25pin cable to use the modem.
I scrapped that idea in favour of making up an adaptor that would convert
the BBC's 5pin domino to a 9pin D plug so that normal PC cables could plug
into it. The reason I did this was because I could then use both the normal
modem cable and a direct null modem cable with the same adaptor. Also if
there is or becomes available software to drive a serial mouse with a BBC I
could plug such a mouse straight in. Last of all it was a lot simpler than
having to work out which pins have to be shorted together in the 25way
connector. The actual connections were not too difficult except for the
Master manual describing TX and RX as data out and data in but luckily the
A3010 manual confirmed which was which. Serial ports are always a bit
confusing I find and the way things work varies depending on device it
seems. I especially hate the way 9pin and 25pin connectors both use pins 2
and 3 for input and output but they are the reverse of each other. The other
point about the BBC is the fact the plug can go in two ways making it easy
to create problems for yourself. Once you've made the adaptor, stick on a
little label saying 'TOP' on the din plug and wrap some selotape round it to
seal it on. It saves problems later. The actual connections are simple
enough TX to TX, RX to RX, CTS to CTS, RTS to RTS and ground to ground.
Anyone who wants all the bits for the cable just send me £4 inclusive. £7 if
you want it made up for you. I'd better point out that the adaptor does add
another point where there is some signal loss, as opposed to a single one-
piece modem cable, but its highly unlikely that it will cause any problems.
The adaptor is necessary if you buy a cheap modem that has a captive cable.
I know someone who has such a modem. A 14,400 originally meant for a PC and
he made an adaptor cable for his Mac. This was successful but he has to use
Xon/Xoff instead of hardware handshaking, although this may be more to do
with the Mac's serial ports than the cable itself. Anyway my cable is a
success and only took about ten minutes to make.
The next problem was the software itself. I know Terminal is built in but I
haven't a clue how to work that and from the looks of it is very basic and
unfriendly. Ideally I would have liked a Comms package that made use of the
second processor in the Turbo but to be honest I don't have a great deal of
knowledge on BBC comms software and apart from the comms part of Mini
Office couldn't name another Beeb comms package. I didn't want to buy a
commercial package and instead had a look around for a PD/Freeware package.
I downloaded Jterm from either Arcade BBS or 23rd Hour I'm not sure which
one it was. One of the most surprising things about it, is it was written in
1994 which makes it quite a recent development for the BBC. I'm more used to
seeing dates from the late 80s. It is actually a ROM image and so you need
Sideways RAM. Once loaded with the usual *SRLOAD JTERM 8000 7 and then a
CTRL-Break its activated with *TERM. It defaults to Mode 7 but it can go
into Mode 0 with *TERM -L0. The options screens are easily accessed with the
function keys and its all pretty easy to pick up.
Although it always helps if you do yourself a printed version of the
instructions which runs only to about 4 or 5 sheets. It defaults to 9600
baud and to be perfectly honest this is probably the safest you can go speed
wise. It seems an unwritten rule that you never use the fastest speed a
computer supports but the one before it. So in this case the maximum speed
of 19,200 was not reliable but 9600 seemed fine. It may be that if the comms
software worked over the tube then the extra speed would enable greater
success at 19,200. I know the A3010s serial ports work well if you're using
just the comms software but if you're multitasking other applications the
serial port becomes less reliable at the higher speeds. Its fair to say that
a 2MHZ 65C12 on its own would really struggle with a 19,200 baud rate. The
A3010 struggles with anything over 38,000.
With my Master setup I phoned my local Bransyeo BBS and managed to log on
but the screen was full of garbage because its an ANSI only BBS. I could
make out the normal text between all the wierd characters but it wasn't
exactly pleasant. ANSI is an 80 column 16 colour specification and so the
BBC's lack of colour ruins it. There may be a way of improving the look of
ANSI BBS's by the software automatically filtering out the codes but I
wouldn't know how to do that. It would also be annoying that you have to
downlaod characters that are being ignored anyway. I phoned Chaos Cottage
down in Cornwall which has a large BBC area dedicated to Solinet plus
support for the Arc, PC and Amstrad PCW/CPC and this was far more
successful. It doesn't force ANSI graphics on you so it can be used
properly. I never actually uploaded or downloaded anything using Jterm but
it does have the Xmodem protocol and a few others built in. The software
itself seems buggy as the author admits, but it can be mastered and I would
certainly recommend it over some of the very early packages.
The only of 8bit users out there using modems is quite high. I've come
across Spectrum users, PCW users and of course BBC users.
Can anyone using their BBCs for Comms write in with what they use? Also, is
there a tube compatible Comms package which can use the Zmodem protocol?
4WL