RCA COSMAC Operator's Manual page 64

Sample Program System (cont'd)
The logic required on the additional module is strictly
for input and is based on the arrangement shown in Fig.13
of the Microprocessor Manual. The output port required
by the control program is fully implemented in hardware
by the Byte I/O module. Thus the new plug-in contains
the following:
F-P
ENTER
... ' CD4011
•
-L
CD4013
EFI- N
I
S
Q
C
• •
,
I
R C
0
0 S
V OO
V OO
-
.
.
8 TOGGLE SWITCHES
" 1 "
V OO
~
IN
0 - P TO
IN
7-P PI-3 TO PI-IO
"0"
~~~~~~~~(8~)~~~~~~~~~~(SLOTI9)
r<>
-
' :"
Fig.18: Sample Program Interface
Since slot 19 is wired to IOF-P and SI06-P, two bytes
in the Sample Program listing on page 64 (Microprocessor
Manual) must be changed as follows:
Address DODD - change 68 to 6F
Address ODIC - change 60 to 66
Now the two IC chip interface shown in Fig. 18 will
properly execute the "Sample Program".
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