Connect Four ProjectFall 2011Anna Grimley & Josh MandichLab Section: F

Connect Four Game

Objectives1. Create Verilog Code for Connect Four Logic2. Synthesize Code3. Create Layout

Project Constraints

Inputs Outputs

PONE 0:3 Red 0:15

PTWO 0:3 GREEN 0:15

START PONEWIN

PTWOWIN

0Boolean: 0000

10001

20010

30011

40100

50101

60110

70111

81000

91001

101010

111100

121101

131110

141110

151111

Game as Two PlayersMust use 4x4 matrix of LED’sPlayer must be able to start by using the START inputPONE always starts, PONE&PTWO can not give input simultaneously Player must be able to start by using the START input

Other times to think aboutMust not allow a player to overwrite previous selection.Must not allow player to play out of turnGame must stop when player winsA 4x4

Strategy• Keep code simple• Take into consideration what is synthesizable and

what is not• Start building code early and seek for help

Truly elegant design incorporates top-notch functionality into a simple, uncluttered form.

— David Lewis

Verilog HDL• At Start==0

sets all registers to 0. and turn=1

• Continues to check PONEWIN & PTWOWIN are zero at all steps

Verilog Code

Input and Start

Verilog Code

Light LED from User Input

Verilog Code

Detect Winning Input

Testing Verilog Code

Test Bench• Wanted to Test

Player can not keep playing when LED already selected

• Proved that PONEWIN would work when PONE had won

VSIM Testbench Output

SynthesizingSchematic of elaborated Verilog Connect 4. (Code in RTL compiler)

SynthesizingSchematic of Optimized Connect 4(Code integrated with OSU lib)

SynthesizingSchematic of Optimized Connect 4(Code integrated with OSU lib)

Synthesizing Schematic cell view of synthesized Connect4 code in Virtuoso

Layout• Initial Floor Plan• Floorplan layout

with power rings

LayoutCell and IO pin Placemnent

Layout• Power and Ground

Routing• Power Routing

between die I/O and standard cells

LayoutFinal layout view of Connect4.v in Encounter with filler added

Yay! Celebrate!!!

Final LayoutUsing OSU_stdcells_ami05 library.

Major Take Away’s• Understand what verilog can be synthesized and

what can not• Keep Verilog simple• Be patient with synthesizing and layout in

encounter/virtuoso• Spending time on HDL pays off in synthesizing

Ha Ha HaNot this Connect Four