7220C_7220T_OperatingAndProgrammingManual_07220-90003_229pages_Feb81.pdf http://www.hpmuseum.net/document.php?hwfile=1567
Page 195, Connecting the RS-232-C Interface On Thu, Dec 5, 2019, 3:34 PM Jules Richardson via cctalk < cctalk@classiccmp.org> wrote: > > Hi all, > > I picked up an HP 7220C flatbed plotter the other day which (after freeing > the stuck carriage) is responding to panel commands in 'local' mode. For > the terminal RS-232 interface, does anyone happen to know: > > a) The character size (7 or 8 bits)? > > b) If the connection between terminal and plotter is supposed to be > straight through (i.e. 1:1 pin mapping), null modem, or something else > entirely? > > I'm not sure if the plotter considers itself DTE or DCE, given that it has > a modem output port (i.e. it sits partway along in the chain of things). > > Oh, there's a "conf test" switch setting on the back - does anyone know > the > purpose of that? I'm wondering if it's supposed to echo back to the > terminal any data that's sent to the plotter, but that's purely a guess. > Sadly there don't seem to be any docs online (or much in the way of any > info, to be honest). > > thanks, > > Jules > > >
