Quest Engineering SUPER ELF User manual

SUPER
ELF
AN 1802 BASED
MICRO COMPUTER
BY
QUEST
COPYRIGHT 1977 BY QUEST ELECTRONICS

If you have any questions
or problems with your SUPER ELF
Write to:
SUPER ELF
QUEST ELECTRONICS
P.O. Box 4430
Santa Clara, California 95054

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CONTENTS PAGE
I INTRODUCTION
1. Manual contents 5
2. External Connections 5
II OPERATION
1. Hardware Assignments 6
2. Controls Description 6
3. Indicators and Displays Description 7
4. Operation without the ROM Monitor 8
5. Operation with the ROM Monitor 9
6. Using Single Step/Slow Step 10
III LOGIC DESIGN DESCRIPTION
1. Hexadecimal Keypad 11
2. Control Circuit: G R S W 13
3. Control Circuit: M P I L 15
4. Display Control 17
5. ROM/RAM Select 17
6. RAM/ROM Memory 19
7. State/Mode Display 19
8. Output/Data Display 23
9. Address Buffers/Latch 23
10. Address Display 25
11. Power Supply 25
12. Memory Saver 25
13. Video Generator 29
14. I/O Port Select 29
15. Q Circuit 29
16. Clock Generator 30
IV EXPANSION BUS
1. Capabilities 31
2. Constraints 31
V TROUBLESHOOTING
1. CPU Mode Control 34
2. Hexadecimal Keypad 34
3. Video Display 35
4. Data/Output Display 35

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5. Address Display 35
6. ROM/RAM Select 35
7. Load Mode 35
APPENDIX A PARTS LIST AND ASSEMBLY INSTRUCTIONS
1. Parts List - Basic 43
2. Parts List - Optional Low Address Display 46
3. Parts List - Optional High Address Display 47
4. Parts List - Optional Memory Saver 47
5. Parts List - Optional Accessories 48
6. Assembly Instructions - Basic 48
7. Assembly Instructions - Low Address Display 52
8. Assembly Instructions - High Address Display 52
9. Assembly Instructions - Memory Saver 52
10. Initial Checkout 53
APPENDIX B. DATA SHEETS
1. CDP1802 Microprocessor 57
2. CDP1861 Video Display Controller 78
FIGURES
1. Hexadecimal Keyboard 12
2. Control Circuit: G R S W 14
3. Control Circuit: M P I L 16
4. Display Control / ROM/RAM Select 18
5. RAM/ROM Memory 20
6. State/Mode Display 21
7. Output/Data Display 22
8. Address Buffers/latch 24
9. Address Display 26
10. Power supply / Memory Saver 27
11. Video Generator / I/O Port Select / Q Circuit / Clock 28
12. Expansion Bus Connections 33
13. Component Layout V 1.0 36
14. Component Layout V 2.0 37
15. Board Wiring Pattern V 1.0 Front 38
16. Board Wiring Pattern V 1.0 Back 39
17. Board Wiring Pattern V 2.0 Front 40
18. Board Wiring Pattern V 2.0 Back 41
19. Power and Ground Connections 42
CHANGE NOTICES 89

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I. INTRODUCTION
1. MANUAL CONTENTS
This manual consists of 5 major sections and two appendices. These 5
sections cover a) a description of the external connections required, b)
detailed descriptions of the operational features and how to use them, c)
logic diagrams/schematics and descriptions of how the logic works, d) the
expansion buses and how to use them, and e) hints on troubleshooting in
case of difficulty. Appendix A Contains parts lists and assembly instructions
for the basic SUPER ELF and available options. Appendix B contains
complete data sheets on both the 1802 CPU and the 1861 video graphics
generator.
2. EXTERNAL CONNECTIONS
All external connections are located in the upper left hand corner of
the printed circuit board. These connections are summarized here and
discussed in more detail in both Section III Logic Design and Appendix A
Parts List and Assembly Instructions. Starting at the upper left-hand corner
and going to the right, the BAT pair of connections are used for the 2.4V
standby Ni-Cad battery included in the memory saver option. Next are the
SW1 connections used to connect the battery to the RAMS (also used in the
memory saver option). Next are the SW2 connections used to disable the
Rams (also used in the memory saver option). Next are the AC connections
which are used to supply power to the board from the supplied plug-in
transformer. Going back to the upper left-hand corner and going down the
left edge is the SPKR connections. This is the amplified output of the Q line.
Normally a speaker is connected here for audio effects. However, these
connections can also be used as a serial output port or a relay driver. Next
are the VID connections which are an amplified composite (sync and video)
video signal of approximately 2 volts peak to peak. This output may drive a
video monitor directly or it may be used to drive an RF modulator to allow
connections to any TV set's antenna terminals. Some RF modulators
available for this use work much better than others. One that has been tested
and approved is the VAMP INC. Model RFVM-1 which is available through
QUEST.

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II OPERATION
1. Hardware ASSIGNMENTS
The SUPER ELF has been designed using the following hardware
assignments.
A. Video Display ON Op Code 62.
B. Video Display OFF Op Code 62.
C. HEX Keyboard Input OP Code 6C.
D. HEX Display Output Op Code 64.
E. Video Display Status Line EF1.
F. Input Switch Status Line EF4.
2. CONTROLS DESCRIPTION
The following is a description of the 24 key keyboard controls.
R RESET - Puts the CPU in the RESET mode. These additional
functions are reset if they were set.
1. Single Step
2. Memory Protect
3. ROM Select
L LOAD - Puts the CPU in the LOAD mode from the RESET mode.
I INPUT - Inputs data from the HEX keypad to the data bus in the
LOAD mode. In the RUN mode the EF4 status Line is LOW while
the key is depressed.
P MEMORY PROTECT - Prevents writing into memory. Useful in
the LOAD mode to verify the load. Cannot be used in the RUN
mode with the basic unexpanded board.
M MONITOR - Selects the on-board monitor. Replaces the first 20
HEX locations in memory with the monitor ROM. Location 20
HEX is used by the monitor, so user programs must not start
before location 21 HEX when using the monitor.
S SINGLE STEP - Allows single stepping through the program one
machine cycle at a time. The stopping point is the negative edge of
the TPA pulse of each machine cycle. This function is used with
the RUN switch. When in the SINGLE STEP mode, the
DATA/OUTPUT displays display the DATA bus.

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G RUN or GO puts the CPU in the RUN mode from either the WAIT
or RESET modes. If single step has been selected. Only one
machine cycle will be executed at a time with each momentary key
depression. Holding the RUN button down will result in slowly
stepping through the program one machine cycle at a time.
W WAIT puts the CPU in the WAIT state if previously in the RUN
state. Puts the CPU in the LOAD state from the RESET state.
Resets memory protect.
0 through F - HEX keypad stores the last TWO key depressions for
logout to the 8-bit data bus. The last key depressed is the least
significant 4 bits of the 8-bit data word.
3. INDICATORS AND DISPLAYS DESCRIPTION
The SUPER ELF has nine LEDS and two HEX displays (4 additional
HEX displays are optional.
A. The LEDS show:
ID FUNCTION
Q Status of Q line
L CPU in LOAD mode
R CPU in RESET mode
G CPU in RUN mode
W CPU in WAIT mode
0 CPU in state 0
1 CPU in state 1
2 CPU in state 2
3 CPU in state 3
NOTE: LED logic is active high.
B. The two HEX displays are normally an output port. However, in
the SINGLE STEP mode, the displays show the contents of the data bus.
C. The 4 optional HEX displays show the contents of the address bus.

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4. OPERATION WITHOUT THE ROM MONITOR
A. Loading programs is done in the LOAD mode. If you have purchased
the address display option, the address just loaded will be displayed
along with the address contents. All loading must start at location 00
HEX.
(1) To load a program
a. Push RESET R key.
b. Push LOAD L key.
c. Push the 2 HEX keypad keys corresponding to the
contents or address 00 HEX.
d. Push the INPUT I switch.
e. The contents of address 00 HEX will be displayed by
the data displays.
f. Push the 2 HEX keypad keys corresponding to the
contents of the next address.
g. Push the INPUT I switch.
h. The contents of tat address will be displayed.
l. Repeat steps f and g until the entire program is
loaded.
(2) To make corrections.
a. Push RESET R key.
b. Push LOAD L key.
c. Push Memory Protect P key.
d. Push the INPUT I key until the preceding location is
reached.
e. Load the HEX keypad with the corrected data word.
f. Push the WAIT W key to enable memory writing.
g. Push the INPUT I key to load the correction data
word.
(3) To run programs.
a. Push the RESET R key.
b. Push the RUN G key. The program will start
executing at address 00 HEX.

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5. OPERATION WITH THE ROM MONITOR
The SUPER ELF monitor allows us to do three things.
A. Loading a program starting at any location.
B. Examine any location in memory (including the monitor itself).
C. Starting a program at any location.
NOTE: This monitor only works with PAGE ZERO (the first 256 words
of memory).
A. To use the monitor to load a program.
(1) Push RESET R key.
(2) Push HEX keys 0 and 2 in that order.
(3) Push the MONITOR M select key.
(4) Push the RUN G key and the data display will indicate 02.
(5) Push the two HEX keypad keys corresponding to the
starting address.
(6) Push the INPUT I key and the Q light will come on
indicating that memory writing is enabled.
(7) Push the two HEX keypad keys corresponding to the data
going into the memory.
(8) Push the INPUT I key and the data displays will display
the memory data just entered.
(9) Repeat steps 7 and 8 for the remainder of the program.
(10) Push the Reset R key when completed.
B. To use the monitor to read out memory contents.
(1) Push the RESET R key.
(2) Push HEX keypad keys 0 and 1 in that order.
(3) Push HEX Monitor M select key.
(4) Push the RUN G key and the data display will indicate 01.
(5) Push the two HEX keypad keys corresponding to the
starting address.
(6) Push the INPUT I key.
(7) Push the INPUT I key again and the data display will
indicate the contents of the specified memory location.

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(8) Continue to push the INPUT I key to step through the
memory contents one at a time.
(9) Push the RESET R key when completed.
NOTE: The contents of the monitor may be read out by using memory
location 00 in step 5.
C. To use the monitor to start execution of a program at any
location.
(1) Push the RESET R key.
(2) Push the HEX keypad key 0 twice.
(3) Push the Monitor M select key.
(4) Push the RUN G key and the data display will indicate 00.
(5) Push the two HEX keypad keys corresponding to the
starting address.
(6) Push the INPUT I key and the program will start
executing.
6. USING SINGLE STEP/SLOW STEP
The SUPER ELF has the ability to step through programs one
machine cycle at a time. Execution is halted at the negative edge of the TPA
signal in each machine cycle. At this point the CPU is in the process of
executing the current instruction cycle. The instruction set timing diagrams
in APPENDIX B should be consulted to determine the hardware state
corresponding' to the instruction being executed.
The single step/slow step mode may be entered from the RESET state
or the WAIT state by pushing the Single Step S key. Pro- gram execution
may then be started or resumed by pushing the RUN G key. A single push of
the RUN G key will advance the program one machine cycle. Holding the
RUN G key down will advance the program at a rate or approximately 1 to 2
machine cycles per second. Re- leasing the RUN G key will stop execution.
Pushing the WAIT W key disables the single step mode and then pushing
the RUN\ G key resumes normal speed operation.