The DECmate II (VT100 housing) has the ability to
download code into
the PDP-8 through the terminal port via a special control sequence. I
haven't tried it on mine yet.
Do you know what the control sequence and data format is and/or what
manual documents it?
I though the sequence went VT78 (in VT52), DECmate/VT278 (in VT100),
DECmate II (in big PC like case), DECmate III (in little PC like case),
DECmate III+ (same)