C64 Serial Port finished!

[Jim Brain]

> I'm hoping the library will work with Lantronix-like things like tcpser.
> It does depend on DCD being up when a connection is active, however, and
> only Jim can say if it does that. (Jim?)
>   
It does, if you use the "brain" cable mods (take null modem cable and 
cut off DSR pin to 64).  tcpser and tcpser4j flip DTR to effect DCD on 
the receiving end, but null modem cables normally hook DSR and DCD 
together.  Cutting the pin lets DSR float high (which is fine) and DCD 
then tracks the connection state.  For a user port system, the cut is 
not needed, as user port code typically ignores DSR, but the 6551 carts 
absolutely will not work if DSR is tied low.

> So did I :) of course, it was just dialing into a terminal server. For a
> long time my 128 was my only method of Net access, using Kermit and a ZOOM
> external modem.
>   
My first telecommunications was over rural lines using a brand new CBM 
1600 non-dialing direct connect modem.  300 bps was not possible, so I 
conversed with friends at 150 bps.  Later, I upgraded to a 1650 clone 
call the MasterModem that got me on at 300 bps.  After lightning took 
the modem out, I got the ill-conceived 1660 300 bps modem, and when 
lightning took it (good riddance) I got a Zoom 2400 that I used at 2400 
with Novaterm.  Given the readership, I'll note I took the system to 
college, where I used it for term papers and general work until 1992, 
including doing my Physics online homework on the University of Illinois 
PLATO system from my dorm room using some PLATO emulator for the 64.  It 
sure beat fighting for a plasma PLATO workstations at the locations on 
campus.

Getting my first taste of UNIX via the 64 and Novaterm at 2400 bps was 
fun too.  I think all the student accounts were on a Sequent 68K CPU 
based box, as I recall, but I could be terribly wrong.  In any event, I 
still use tricks I learned them (screen, anyone) to this day.

jim



-- 
Jim Brain, Brain Innovations
brain at jbrain.com 
Dabbling in WWW, Embedded Systems, Old CBM computers, and Good Times! 
Home: http://www.jbrain.com