Overview

This homework set explores the idea of hardware/software co-design. Beginning from a single set of product specifications, you will formulate a software-only implementation, making note of which areas of design are particularly difficult, inefficient, or troublesome. Next, you will create a hardware-only implementation, again making note of difficult aspects of the design. Finally, you will create a hybrid design, in which the "difficult software" is done in hardware, and the "difficult hardware" is done in software.

Product Specification: 24-Hour Digital Clock

1. Hardware environment is either the D2SB/DIO4 or the D2E/DIO1 board combo
2. Hours (HH) range from 00 to 23; minutes (MM) range from 00 to 59; seconds (SS) range from 00 to 59
3. Time will be accurate to ±1 second per day
4. Master reset implemented by pushbutton on D2SB (or D2E) system board
5. A blinker is implemented by any discrete LED
6. Use the DigitDisplay IP to drive the four-digit display
7. Normal display mode is HH.MM
8. Alternate display mode is MM.SS
9. A slider switch selects between the two display modes
10. Time is adjusted using a total of five pushbuttons as follows:
    1. Press and hold one of three pushbuttons to select adjustment of either HH, MM, or SS
    2. Press one pushbutton to increment selected quantity by one unit
    3. Press another pushbutton to decrement selected quantity by one unit

Part A

1. Develop a software-only implementation based on the PicoBlaze processor; use the DigitDisplay IP as the only additional hardware component (two registers would also be required, one for each 8-bit input of the DigitDisplay IP). Document your design as a flow-chart and as a PicoBlaze assembly language code listing.
2. Write a paragraph or two that describes the aspects of the design that are particularly difficult, inefficient, or troublesome.

Part B

1. Develop a hardware-only implementation. Document your design as a block diagram and as a Verilog description listing.
2. Write a paragraph or two that describes the aspects of the design that are particularly difficult, inefficient, or troublesome.

Part C

1. Develop a hybrid implementation, with the "difficult software" done in custom hardware, and the "difficult hardware" done in custom software executed by the PicoBlaze processor. Document your software design as a flow chart and a PicoBlaze assembly listing; document your hardware design as a block diagram and as a Verilog description listing.
2. Write a paragraph or two that describes your experience creating the hybrid design.

Optional Extra Credit

Any or all of the following (each will receive its own extra credit points):

1. Demonstrate correctly-operating simulation of design from Part A
2. Demonstrate correctly-operating simulation of design from Part B
3. Demonstrate a functional implementation of Part C in actual hardware.