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Further reading □ Overview □ History □ Charactron Tube □ Fonts □ SC4020 Speed □ Architecture □ Tube □ 16mm Camera □ Hardcopy □ Vought Camera □ Order Code □ Printing □ Drawing □ Film Production □ UAIDE 1970 □ UAIDE Contents 1964-1973 □ UAIDE Papers □ 1968: Honey □ 1968: Sarno □ 1968: Yarbrough □ SC4020 Manuals □ Engineers Training □ Information Manual □ Programmers' Reference Manual □ Other □ Diagrams drawn by computer
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⟶ ACL ⟶ Technology ⟶ SC 4020
⟶ ACL ⟶ Technology ⟶ SC 4020
ACL ACD C&A INF CCD CISD Archives
Further reading ⇓

□ Overview
□ History
□ Charactron Tube
□ Fonts
□ SC4020 Speed
□ Architecture
□ Tube
□ 16mm Camera
□ Hardcopy
□ Vought Camera
□ Order Code
□ Printing
□ Drawing
□ Film Production
□ UAIDE 1970
□ UAIDE Contents 1964-1973
UAIDE Papers
□ 1968: Honey
□ 1968: Sarno
□ 1968: Yarbrough
SC4020 Manuals
□ Engineers Training
□ Information Manual
□ Programmers' Reference Manual
Other
□ Diagrams drawn by computer

SC4020 Order Code

Introduction

The SC4020 order code consisted of single 36-bit word instructions in seven different instruction formats. The addresses are with respect to the SC4020's 1024 by 1024 plotting area.

TYPE 1 05 OPCODE 67 817 X 1823 C 2425 2635 Y TYPE 2 05 OPCODE 635 TYPE 3 05 OPCODE 67 St 817 X 1825 Sb 2635 Y TYPE 4 05 OPCODE 611 1217 N 1822 23 I 2435 TYPE 5 05 OPCODE 611 C1 1217 C2 1823 C3 2429 C4 3035 C5 TYPE 6 01 11 27 DX 817 X 18 SX 19 SY 2025 DY 2635 Y TYPE 7 05 C1 611 C2 1217 C3 1823 C4 2429 C5 3035 C6

SC4020 Instructions
Opcode
in Octal		 Format Name Operation
00 1 PLOT Plot C at (X,Y)
02 1 EXPOSE HEAVY Set to Expose Heavy Mode. Plot C at (X,Y)
04 1 EXPOSE LIGHT Set to Expose Light Mode. Plot C at (X,Y)
07 2 IGNORE REST OF RECORD
12 2 STOP TYPE Return to Plotting Mode
20 1 TYPE SPECIFIED POINT Type C at (X,Y). Enter Typing Mode
22 5 TYPE CURRENT POINT Type Ci from current point. Enter Typing Mode
30 3 GENERATE X AXIS vector(X,Y,I,Y) where I=complement(S)
32 3 GENERATE Y AXIS vector(X,Y,X,S)
37 2 STOP SC4020
41 2 SELECT MF CAMERA
42 2 SELECT HC CAMERA
43 2 SELECT BOTH CAMERAS
44 2 EXPAND IMAGE
45 2 REDUCE IMAGE
46 4 ADVANCE FILM Advance Film if I=0
46 4 ADVANCE REPEAT Advance Film and repeat N times if I=1
50 2 PROJECT FORM
56 2 RESET Equivalent to Advance Film, Stop typing, Expose heavy
6 DRAW VECTOR vector (X,Y,X+SX*DX,Y-SY*DY);
SX=+1 if bit 18 =1 else -1;
SY=+1 if bit 19 =1 else -1;
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