13 Apr
2001
13 Apr
'01
9:51 p.m.
I've revisited the RS232 signal definitions and can't see one called
"busy". I
know about software handshaking, and even hardware handshaking, but I don't know
of a 'busy" signal. Which pin is that?
Dick
----- Original Message -----
From: "Tony Duell" <ard(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Friday, April 13, 2001 7:26 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
Oh, most do. The really old ones (Teletypes, Decwriters, etc) don't --
they operate at a baud rate low enough that you can't send characters
too fast for them. But most more recent printers have some kind of
internal buffering and handshaking -- either software handshaking
(XON/XOFF, ETX/ACK) or hardware handshaking (Busy line, for example).
Epsons (and things emulating Epsons, and more recent DECwriters, like the
LA100) seem to put the busy signal on pin 11 (at RS232 levels, of
course). Some other makes (like my Apple LW2NT) use the normal lines
(RTS, DTR, etc) for this.
-tony
At 07:17 PM 4/13/01 +0100, Tony Duell wrote:
Since when do
serial printers have a BUSY line at all? Oh, brilliant... Many serial printers (Epson, etc)
have the busy line on
pin 11. So plug that into an Amiga serial port with a straight-through
cable and you'll cook something in the sound circuitry.