Friden Flexowriter interface timing signals

From: Tom Jennings <tomj_at_wps.com>
Date: Fri Nov 7 12:55:47 2003

I'm making a Friden Flexowriter simulator to bring up my LGP-21
(solid-state follow-on to the LGP-30). I do not have access to the
LGP-21 Flexowriter, which is modified from a "standard" (sic) flexo in a
number of ways (peculiar code set, special fromt-panel switches).

I have hardware documentation for the LGP, which includes a fair chunk
of Flexo data (schematic, etc) but it's not much help with the interface
timing. I think it's likely the signal names are standard (sic) Friden,
but I don't know.

(The simulator will be PIC-based, and will diddle the interface signals
under control of host-resident software, to which it'll talk to via
serial port.)

I'm assuming it's a "busy/done" system, eg. to print, the computer sets
up print data (before point a, below) then asserts the strobe or gate on
(at a). (call it Print Start, or interface "busy"). When the Flexo has
assimilated the data, it asserts Print End, or "done", at b, which
clears Print Start; when Print End deasserts, at c, the interface is
ready to begin the next cycle:

                            a b c
                            +---------+
                            | |
  to flexo START -----------+ +---------------
                                      +----------+
                                      | |
from flexo END ---------------------+ +----


I believe receive is similar, with the directions reverse of course.


Specifically, I can't determine the timing relationships of signals:

(print)
Tx print start?
JL29 print end?

(receive)
Xs receive start?
Sr receive end?
JL12 "start input cycle"
JL11 "end of flex input cycle"

Receive especially bugs me, since it appears to be two sets of handshake
that do the same thing. The descriptions in "quotes" are from the LGP-21
algebraic descriptions of the Flex interface.

(There are also signals JL32, JL33, JL28-20, and LGP-specific Friden
switches "START COMPUTE", and maybe "MANUAL INPUT", which the LGP sees
in some manner.)


Here's the Flexowriter cable end pinouts, if it's any help.



Flexowriter connector (JL) P38, end of cable to J19.
                to/from
                flexo
01 TP5 to Print data
02 TP4 to Print data
03 TP3 to Print data
04 TP2 to Print data
05 TP1 to Print data
06 TP6 to Print data
07 Tx to Print start ("busy")
08 -60V from
09 Sr to Receive end ("done")
10 /BQ from Manual input
11 JL11 from "End of flex input cycle"?
12 JL12 from "Start input cycle"
13 P5* from Receive data
14 /P5* from Receive data
15 P4* from Receive data
16 /P4* from Receive data
17 P3* from Receive data
18 /P3* from Receive data
19 P2* from Receive data
20 /P2* from Receive data
21 P1* from Receive data
22 /P1* from Receive data
23 P6* from Receive data
24 /P6* from Receive data
25 SIGNAL GROUND
26
27 Xs from Receive start ("busy")
28 JL28-20 to
29 JL29 from Print end ("done")
30
31 SIGNAL GROUND
32 JL32 to
33 JL33 from "translator cam"?
34 SIGNAL GROUND
35 117AC to
36 117AC to
37 CHASSIS GROUND
Received on Fri Nov 07 2003 - 12:55:47 GMT