MOUSE Computer Module L6.10

Microcomputer of Oakland University’s School of Engineering MOUSE Computer Microcomputer of Oakland University’s School of Engineering

MOUSE Designed and built in 1979 Based on 6802 microprocessor Hex keypad Six 7-segment displays

6800 Microprocessor Accumulator A Accumulator B Index Register X Stack Pointer, SP Program Counter, PC Condition Code

MOUSE Commands 0. Examine Accumulator A 1. Examine Accumulator B 2. Examine Index Register, X 3. Examine Stack Pointer, SP 4. Examine Program Counter, PC 5. Examine Condition Code Register 6. Offset Calculation 7. Set Breakpoint

MOUSE Commands (cont.) 8. Continue program 9. Single step program A. Automatic data entry B. Back up one byte in memory C. Change byte in memory D. Do - execute program E. Examine memory F. Forward one byte in memory

MOUSE Keypad Decoding 4-to-16 Decoder PA0 PA1 PA2 PA3 CA2 CA1 7 4 1 5 6 9 8 A B C D PA0 + V K W PA1 PA2 PA3 CA1 CA2 4-to-16 Decoder

7-Segment Display

8 8 8 8 8 8 MOUSE 7-Segment Displays a b c d e f PB0 PB1 PB2 PB3 PB4 PB5 PB6 8 8 8 8 8 8 7442 BCD/Decimal Decoder PA[4..7]

8 8 5 8 8 8 MOUSE 7-Segment Displays a b c d e f PB0 PB1 PB2 PB3 PB4 PB5 PB6 1 1 1 1 1 8 8 5 8 8 8 1 1 1 1 1 1 2 3 4 5 PA[4..7] 7442 BCD/Decimal Decoder 0010

CSE171 a b c d e f g 0097 39 C 0098 6D S 0099 79 E 009A 06 1 009B 07 7 009C 06 1

Print Message 0030 CE 0097 LDX #$0097 0033 BD B84C JSR MOVMES 0036 BD B824 JSR SIXDS 0039 20 FB BRA -5

MOUSE Layout Address Bus (16 lines) To outside world PROM 2716 RAM 6810 MPU 6802 PIA 6821 To outside world Data Bus (8 lines)

MOUSE Memory Map Hex Address Device RAM1 (internal) 0000-007F RAM2 0080-00FF PROM B800-BFFF PIA 8000-8003