hsu@eneevax.UUCP (David T. Hsu) (10/19/85)
In article <851017-140850-1769@Xerox> Denber.wbst@XEROX.ARPA writes: >... >Adapting it for the 400 requires removing the 2 ICs on the board and >soldering jumpers from the (now) empty holes to the keyboard socket >in the 400. One can figure out how to do this by reverse engineering >... >I went out and bought one of these keyboards (they look quite nice, and >only $4.95!), but I don't have a TR Manual. Does anyone have the >information I need to make the connections? Thanks. > > - Michel I too bought one, and promptly set about in search of my Dec '82 Creative Computing, from which the following matrix is derived. Note that this is the original 400 keyboard circuits; I haven't finished tracing the 1200 keyboard yet to figure which pins go where. wire # 1 2 3 4 5 6 7 8 ------+---------------------------------------- 9 | brk ctl both shiftkeys in parallel 10 | 7 6 U Y N 11 | J H spc 12 | 8 5 I T K G M B 13 | 9 4 O R L F , V 14 | 0 3 P E ; D . C 15 | < 2 - W + S / X 16 | > 1 = Q * A atr Z 17 | bs esc ret tab cap also, there is another set for the system keys 18 19 20 21 22 reset opt selec start The article implies that these numbers refer to those of the wiring trunk at the 400's membrane end. I haven't figured out yet the values for the extra pf keys, but it's a pretty good bet that they sit in the blanks for rows 10 and 11. -dave -- ------------------------------------------------------------------------------- David Hsu Across the net... USnail: Communications & Signal Processing Laboratory hsu @ eneevax.umd.edu Department of Electrical Engineering hsu @ sphinx.ee.umd.edu University of Maryland hsu @ mustafa.ee.umd.edu College Park, MD 20742 hsu @ umd2.arpa BITnet: CF522 @ UMDD hsu @ mit-prep.arpa "You see? You SEE???"
hsu@eneevax.UUCP (David T. Hsu) (10/19/85)
Well, I sat up and figured out the pin correspondences so you wouldn't have
to. It seems Atari saved space (and wire) by moving those chips to the
keyboard, and so now, here is are the translations from the new wiring
to the old. Old pin numbers refer to my previous posting.
new pin # old posting pin #
IC #1 14 1
1 2
2 3
15 4
4 5
13 6
12 7
5 8
ribbon pin #1 9
IC #2 1 10
2 11
15 12
4 13
5 14
14 15
13 16
12 17
ribbon pins 10 18 reset
11 19 option
12 20 select
13 21 start
14 22 (common to above)
I believe the matrix is correct, since I've tried at least two intersections
for each wire number. Beset by a flakey meter, it took me nearly 20 minutes
to confirm my suspicion that old pin 9 was connected to ribbon pin 1.
BTW, ic#1 refers to the one on the left, between the m and comma keys, and
just in case somebody doesn't have the red stripe, ribbon numbers are numbered
from the spacebar side to the edge.
Get those 400's doing something. NOW!
-dave
--
-------------------------------------------------------------------------------
David Hsu Across the net...
USnail: Communications & Signal Processing Laboratory hsu @ eneevax.umd.edu
Dept of Electr Engr, Univ Md hsu @ mit-prep.arpa
College Park, MD 20742 hsu @ umd2.arpa
UUCP: {seismo,allegra}!umcp-cs!eneevax!hsu BITnet: CF522 @ UMDD
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