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Messiah College Engineering Department Senior Project Final Design Report

The Biodiesel Project May 8, 2003

Team Members: Christopher Smith Michael Emberger Walter Guzik Shawn Stauffer

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Table of Contents

1. Preface………………………………………………………….…..….1

A. Abstract………………………………………………………...….1 B. Acknowledgements……………………………………………..…1

2. Section 1 – Introduction……………………………………………….1 A. Description………………………………………………………...1 B. Literature Review………………………………………………….2 C. Solution……………………………………………………………3

3. Section 2 – Design Process…………………………………………...4 4. Section 3 – Implementation……………………………………..……6

A. Construction….………………………………………………..….6 B. Operation……………………………………………………….…9

5. Section 4 – Project Management…….………………………….…..10 6. Section 5 – Budget…………………………………………………..10 7. Section 6 – Conclusions……………………………………………..12 8. Section 7 – Recommendations for Future Work…………………….13 9. Appendices…………………………………………………….….…14

A. Appendix A – Gantt Charts……………………………………...14 B. Appendix B – Circuit Diagrams for Control System……………16 C. Appendix C – Pictorial Documentation…………………………17 D. Appendix D – Operator’s Manual………..……………………..33

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BIODIESEL

PREFACE

ABSTRACT

The project group EAT Biodiesel, consisting of Chris Smith, Shawn Stauffer, Wally

Guzik and Michael Emberger intended to construct an automated facility for the

conversion of waste canola oil (WCO) into a viable fuel known as biodiesel. With the

funding of the Messiah College Department of Engineering, the group entered the project

under the supervision of Professor Carl Erikson planning to use the processed fuel as a

supplement for the diesel vehicles on campus. While liability concerns prevented the

testing of the fuel within the vehicles that we intended, the automated facility still

underwent construction.

ACKNOWLEDGEMENTS

Throughout the course of the project, we received information and supplies from people

that deserve thanks. As a result, we would like to thank Mr. John Meyer, Mr. Earl

Swope, Dr. Robert Martin, Dr. Gary Emberger, Mr. Mike Pelly, Dr. Job Ebenezer, Mr.

Richard Fritz, Dr. Donald Pratt, and our advisor Professor Carl Erikson.

SECTION 1 – INTRODUCTION

DESCRIPTION Biodiesel is an environmentally friendly diesel compatible fuel produced by chemical

reaction of fresh or waste cooking oil with methanol and sodium hydroxide. We plan to

research, experiment and develop an automated process facility to produce biodiesel

using waste cooking oil from Messiah College Dining Services, for use by the college in

various diesel fueled applications. Our production plant will consist of a setup of

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multiple tanks, pumps, and valves wired to a central control system. Each tank serves as

a unique part of the reaction through processes of heating, mixing, washing, and storage.

A structure built to accommodate the requirements of our project houses all of this

equipment.

LITERATURE REVIEW During our research concerning the available methods for producing biodiesel, we visited

several web sites searching for the best available mixture process along with information

about the most advanced methods of completing that process. First we visited

www.biodiesel.org, the official site of the National Biodiesel Board (NBB). This site

contains information about the latest news involving biodiesel production and

development as well as information about the comparison between biodiesel and regular

diesel performance. It also provides a list of fleets and service companies that are

currently using biodiesel along with a list of several industrial manufacturers. Our

second Internet source is www.journeytoforever.org, which contains a variety of recipes

for producing biodiesel. These recipes vary in complexity from a “foolproof” method to

more complicated procedures involving more precise methods. The site also has

information on various biodiesel production systems in existence. Most of the systems

on this site were designed for a similar scale to our project but did not use any

automation. In addition, we researched several of the sites for the manufacture of

biodiesel on an industrial level that apparently use an automated process but only for

large volumes of fuel. The site http://www.superiorprocesstech.com/ even claimed to

possess designs for continuous along with batch production automation, but we could not

locate any further information regarding their progress. Consequentially we still feel that

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our goal to automate the process for moderate volume batches will contain many

challenges.

SOLUTION

To complete our project within the given parameters we made several important

decisions that helped us overcome the difficulties that arose. During our research, we

discovered many helpful facts about biodiesel production that encouraged our design

process. Primarily we discovered that many people produce small batches of biodiesel

using readily available parts such as spare motors and old 55-gallon drums. While other

sites boasted large batch production in more impressive facilities, some of which offered

information on a continuous batch process we felt that given our time and monetary

constraints to follow the backyard model of using recycled parts.

Despite this decision, our initial plan also resulted in some difficulties with the monetary

limits of the project due to our desire to produce a lasting facility using optimal parts. As

time progressed, however, we decided that completing the project held greater weight

than acquiring ideal components. Consequentially, we sought and received permission to

construct the majority of our facility out of second hand materials that functioned well for

the required task but did not meet our ideal specifications. This decision relieved the

burden of large debt that we once imagined along with providing a way for us to begin

construction more quickly using parts available in the shop. Resultantly, our structure

now stands on Professor Erikson’s farm ready to produce fuel.

For the electronic elements of our project, we relied heavily on donations and free

samples while completing several debugging cycles to ensure the reliability of the control

program. We made this decision in light of the advice given to us by our advisor that

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interfacing software usually tends to complicate a project as a bugaboo. A problem that

did arise within this component of the project, however, was that the supplies we

expected to see available to us often required purchasing due to the unique output

demands of the mechanical elements. Thankfully, we still possessed enough time and

money to counteract this discovery by purchasing the necessary parts.

SECTION 2 – DESIGN PROCESS

Using the data collected from our experiments in the fall with the development of

Biodiesel in the chemistry lab we designed our facility to work through a system of

several tanks controlled by a central electronic program. This design relies on a two story

structure to produce a gravitational feed to produce sufficient fluid flow to the lower

level. On the top level, we placed the waste canola oil (WCO) storage tank along with

the methanol tank and a small mixing tank designed to produce the sodium methoxide

through stirring. Beneath that on the first level, rest the central mixing tank along with

the washing tank that feeds to a Biodiesel storage tank.

Initially we also planned to include a sodium hydroxide tank. However, due to feasibility

concerns within our time limit we elected simply to place the required amount of sodium

hydroxide within the small mixing tank before initiating the production cycle. Another

modification to the original design is the new placement of the methanol tank on the top

level. Previous designs relied on a pump to transport the methanol from a tank on a

lower level to the elevated small mixing tank. While this design was certainly feasible,

we elected to avoid the cost of an additional pump by reducing the amount of stored

methanol and placing the truncated tank directly above the small mixing tank for a

gravitational feed. Further modifications in this vein include the elimination of the

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glycerine and waste water storage tanks. We now intend to release both materials into

much smaller containers than previously planned.

Furthermore, our original plan to include several float switches to determine fluid level

found modification again due to budget concerns. While our original concept included

purchasing several expensive switches, our current facility utilizes a system of magnets

and reed switches with empty jars serving as the triggering floats. Similarly, our design

calling for a thermocouple was exchanged to use a LM-35 temperature sensor at the end

of a metal shaft so that our control system can measure the temperature more accurately.

Another difference is the type of valves used in the system. While we wanted to comply

with the strict ASTM suggested materials list given in standard D6751-02 for Biodiesel,

we found that expense of purchasing these materials far exceeded our budget. Faced with

this difficulty we decided to use valves that used parts not on the recommended list as

donated materials to our project.

In order to mix the fluids in the two mixing tanks we originally planned to use delrin

stirring bars driven by a single motor. When we took a closer look at the cost of delrin,

however, we chose to alter the design to use a steel bar in the central mixing tank. In

addition to this change, we opted to use two bilge pumps to create a vortex in the second

mixing tank rather than any stirring bar.

On the electrical side of the project our design also changed to include the use of two

power supplies rather than one to meet the demand of the mechanical components.

Another significant alteration is the use of a test board for the Motorolla 68HC11 chip

that connects to the system with a breadboard rather than building a board for it from

scratch or using LABview.

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SECTION 3 – IMPLEMENTATION

CONSTRUCTION

The construction process began when we attempted to build funnels out of sheet metal to

attach to the bottom of the washing tank and mixing tank. After several unsuccessful

attempts with the help of John Meyer, we decided to order pre-made funnels. When they

arrived, we cut circular holes in the bottoms of the barrels and welded the funnels so that

they recessed into the tanks. Silicone Caulk was used to seal the edges of the funnels to

the walls of the barrels. The washing tank and mixing tank also received three legs each,

which were steel angle welded to the side of the tank, as well as a sealing plate and valve

fitting welded to the bottom of the funnel.

The first tank that we built was the washing tank. We began this process by welding

eight pieces of steel angle into the funnel with four holes drilled through the vertical

section of each one. Following this procedure, we routed perforated plastic fish tank hose

through the holes in four concentric rings. To insure the desired flow of air through the

hose we placed a screw in one end of each ring, while the other connected to a brass

fitting through the side of the tank wall. On the other side of the tank wall, the brass

fittings connect to two air pumps to provide air pressure to the bubbling hoses in the tank.

A pipe fitting is welded to the side of the tank for drainage of biodiesel through a valve.

Next, we built the mixing tank. A central shaft with a mixing bar relies on two bearings

supported by cross members for support, one welded to the funnel and the other bolted

across the top of the tank. After this construction, we attached the motor that drives the

mixing shaft through a mounting on a tension adjusting plate on the outside of the tank.

Another feature of the mixing tank consists of the box housing the heating elements

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welded at an angle onto the side of the tank, within which the three immersion heaters

protrude into the tank. Near these heaters, silicone sealant glues a bilge pump to the

funnel for biodiesel removal through a house that travels to the washing tank. There is

also a hollow pipe sealed on one end welded through the tank wall, which contains a

temperature sensor.

The washing tank and mixing tank also contain liquid level switches, two in the washing

tank, and one in the mixing tank. An attachment on the lid of a glass pickle jar allows the

jar to slide up and down on two metal rods as the liquid level rises or falls. A glass tube

sealed at the bottom runs vertically parallel to the path of the jar. A reed switch housed

in the glass tube at the desired level then activates when a magnet attached to the jar

passes by. The triggering of these switches then sends a signal to the control system

alerting the program to operate the valves controlling the fluids involved in the steps of

the process near the switch.

The methanol holding tank and small mixing tank were constructed as a single unit. The

bottom sections of two barrels were stacked vertically and held apart by steel angle. The

upper tank (methanol) has a pipe connection in the bottom. The lower tank (small mixing

tank) has two pumps glued with silicone sealant along the tank walls at the bottom to

provide a circular mixing flow. In addition to the pumps, this lower tank also contains a

pipe connection in the bottom with a screen over the hole to prevent un-dissolved sodium

hydroxide from escaping. The waste vegetable oil is simply stored in a barrel with a pipe

connection in the bottom.

The primary construction of the electrical system involved using one of the old Motorola

68HC11 microcontroller boards. The test switches, potentiometer, and LEDs used in the

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control system were connected to the board on the breadboard. The two power supplies

and the relay board were constructed separately from this breadboard.

Each of the power supplies was designed to take in a 60Hz 120Vac signal, and change it

into a DC voltage. The first power supply was simply a ten to one 30 amp transformer

that ran through a 25 amp full wave rectifier. This provided the necessary twelve volt,

twenty-five amp DC power that we needed for the motor and the pumps. The second

power supply mirrored the first one, differentiating only in the five volt regulator

installed after the rectifier. We performed this modification to provide five volts of power

to the relays. The five volt regulator also required a heat sink and fan so that it could

handle the amount of current being pulled by the relays.

The relay board is a simple circuit put together thirteen times. The design of the relay

works so that a small amount of current put out as an output from the microcontroller

activates a transistor. This transistor allows the current to flow from the five volts to

ground through the coil of the relay. This completes the relay's connection and sends the

input signal to the device. The input signal is one of the following: either the twelve volts

for the pumps or motor, or a one-hundred and twenty volts AC to the heaters, valves and

air compressors.

The power supplies and the relay circuits were built on used PCB boards that had

mistakes. We removed all of the copper in the etcher and drilled the holes. Soldering

wires between the components achieved the required connections. All of the inputs to the

relays ran to one connector on the edge of the board.

Following the construction of these elements, the microcontroller, along with the two

power supplies, and the relay board were placed inside of a plastic container in order to

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protect them from the elements. Cutting holes into two of the sides allowed for the input

and output wires. Upon placement within the box, we connected each of the boards to

each along with a ground plate manufactured in the machine shop that served as a

common ground for the entire system.

Following the completion of the individual tanks we built a two floor wooden structure to

house the entire system. The waste oil tank and methanol/mixing combination tank are

housed on the upper floor, while the mixing tank and washing tank are on the lower floor.

The structure has a sloped plywood roof and provides protection from precipitation

without wind. There is a ladder on one end of the structure allowing access to the upper

level. An additional feature of the structure is a shelf above the mixing tank that houses

the electrical control system. Once we placed the control system on the shelf, we

measured the assorted lengths of wire required to reach each device, and connected the

relays.

OPERATION

The operation of the overall facility was not as successful as hoped. When the test batch

was initialized, an unforeseen problem was found. This problem resulted from the fact

that the solenoid valves that are being used in the prototype are not ideal for the situation

in which they were placed. The consequences of this are that the valves do not operate as

expected, thus not providing sufficient flow rate for the system. Due to this

complication, it was not possible to completely run a batch of fuel in the final system;

therefore, final results were not obtainable.

The control system operates by using two basic case statements after some initialization

code. Each of the statements either monitors the mixing process or the washing process.

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The actual code is then broken up into five sections. First is the initialization code,

second the mix tests, then the mix paths. After this are the wash paths, then the wash

tests. The initialization code does many things, it sets up the A/D converter, the STAF

flag, the free running counter, and other similar functions. The test sections of the code

correspond to the decision blocks on the flowchart. Each of these sections of code tests

the various inputs to the control system to see what part of the process is active. Once the

code finds a section, it jumps to the appropriate path section of code. These paths tell the

control system what to do with the outputs to the system. After the path is completed, the

program goes to the next case structure.

SECTION 4 – PROJECT MANAGEMENT

The Gantt Charts found in appendix A reflect our proposed schedules for the full project

along with one isolated to the Spring Semester alone contrasted by the actual/adjusted

completion dates for each component.

Through referencing these Gantt Charts, it becomes clear that many of our project

deadlines required additional effort to meet. This trend particularly applies to the time

toward the end of the project due to poor estimates of construction time and unforeseen

problems such as leak prevention and lack of materials. Despite these problems,

however, we still managed to complete the project on time.

SECTION 5 – BUDGET

The following illustrates the difference between our estimates for an ideal facility

using parts that rely solely on the required materials list in the ASTM standard for

Biodiesel contrasted with our actual expenses for the project.

Budget Item Estimated Actual

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Methanol $100.00 $100.00Sodium Hydroxide

$110.00 Donated

Solenoid Valves $2000.00* DonatedPaint $20.00 $20.00Funnels No

Estimate $61.00

Barrels $150.00 $64 Pipe $50.00 $10***Lumber $20.00 $156.52Air Compressors

$50.00 $20.00

Bubble Tubing $20.00** $3.50 Silicone Sealant No

Estimate $4.74

Angle Iron No Estimate

Donated

Pumps $45.00 DonatedMotor $45.00 DonatedStirring Bar $20.00 DonatedHeaters $7.00 $33.00 Thermocouple $22.00 $22.40 Electronics Board

$120.00 Donated

Microprocessor $3.00 DonatedFloat Switches $160.00 $10 Misc Electronics $75.00 $93.75

Total $3,017.00 $588.91Lollipops $144.00 $100.00Adjusted Total $2,873.00 $488.91

*This represents stainless steel valves with neoprene seals. The donated material consists

of brass valves possibly containing rubber seals from the shop supply.

**This represents neoprene hose as the ideal material instead of the more readily

available plastic fish tank aeration hose that we are using.

***This reflects the decision to use standard garden hose to save money rather than using

inflexible steel pipe.

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SECTION 6 – CONCLUSIONS

Through the course of our work, we successfully completed several of our objectives.

We were able to fulfill all of the most defined aspects of our objectives in building the

prototype facility that is capable of making 40 gallons of biodiesel per week through a

two batch cycle. Another success was that the electronics bay that provides the control

system along with the power supplies for the facility runs on only 120 volts of power.

We are confident that any fuel we produce will meet the ASTM standards for Biodiesel

in the same fashion as the test batches that we produced in the chemistry lab with the

same process as well. Our system is constructed such that the fuel will function to the

same level of quality as our most successful batches through the incorporation of the

knowledge we gained about the process in the lab to the mechanical system.

Furthermore, we successfully produced an operation manual for the facility detailing the

proper storage requirements along with the required amounts for the chemicals in the

each batch. Complementing this information is the brief training video that we produced

that shows the system in operation.

We also strove to meet all the safety standards that we could given our budget and time

constraints. To meet our objective in this area we provided safety railing on the second

floor of the facility and detailed the proper precautions needed for the chemical handling

in the operations manual. Unfortunately, we did fail to comply entirely with the

suggested materials list for the process as mentioned earlier. The materials that we did

use, however, will function for the process as a short time solution but may corrode or

lead to sediment build-up in the fuel over time.

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Other than the frustration with trying to obtain the recommended materials, though the

project went well and we feel that our work reflects the best effort that we could put

forward.

SECTION 7 – RECOMMENDATIONS FOR FUTURE WORK

Due to time, money, and budget concerns we were not able to complete the project to our

complete satisfaction. Consequentially, we recommend that any future project that

follow us work on the following list.

A primary concern is the replacement of the parts that do not comply with the suggested

materials list in the ASTM standard. This would include replacing the garden hose with

steel or aluminum pipe, swapping the solenoid valves in our structure for their equivalent

stainless steel counterparts using neoprene seals over rubber, and using neoprene hose

over plastic for the bubbling tubes.

Another issue that requires attention is the structure housing the facility. While very

sound structurally, the assembly remains exposed to the elements in some fashions. To

increase the efficiency of the heat transfer and prevent gelling in cold weather the

structure should be completely enclosed and insulated. In addition, it would assist the

process to insulate the central mixing tank.

Furthermore, the project would benefit from the development of a method to increase the

amount of fully automated elements. Maintenance could be reduced if the methanol and

sodium hydroxide dispersal was not limited to the amount for a single batch.

Additionally, the glycerine and the waste water disposal could benefit from a different

approach to increase the efficiency of the system.

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Appendix A – Gantt Charts Original Gantt Chart:

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Spring Gantt Chart:

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Appendix B – Circuit Diagrams for Control System

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Appendix C – Pictorial Documentation Picture 1: Waste vegetable oil Picture 2: Mixing waste vegetable oil and sodium methoxide solutions

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Picture 3: Glycerin settled from biodiesel Picture 4: Washing biodiesel

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Picture 5: Water settled after washing Picture 6: Testing wash-water PH

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Picture 7: Processed biodiesel Picture 8: Steel funnel for bottom of mixing and washing tanks

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Picture 9: Steel brackets in wash tank funnel to hold bubble hoses Picture 10: Funnel welded into washing tank

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Picture 11: Bubble hose connectors in wash tank wall Picture 12: Float switch supports

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Picture 13: Float Switch Picture 14: Completed wash tank

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Picture 15: Bottom bearing mounted in funnel for mixing tank Picture 16: Mixing shaft

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Picture 17: Top bearing mounted in mixing tank Picture 18: Pulley mounted on mixing shaft

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Picture 19: Motor mounting plate on mixing tank Picture 20: Motor, belts, and pulley on mixing tank

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Picture 21: Heaters for mixing tank Picture 22: Heaters mounted in box

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Picture 23: Heater box mounted on mixing tank Picture 24: Completed mixing tank

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Picture 25: Electrical box Picture 26: Electrical box and air pumps on control system shelf

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Picture 27: Methanol holding tank Picture 28: Small mixing tank

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Picture 29: Wood structure housing system Picture 30: Side view of structure, washing and mixing tank visible

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Picture 31: Solenoid valve on wash tank Picture 32: Testing biodiesel in Volkswagen Jetta

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Appendix D – Operator’s Manual

Section 1 – Basic Operation

To operate the automated biodiesel facility, begin by ensuring that the storage tanks

possess the proper amounts to initiate the cycle. Both the drainage storage tanks and the

chemical storage tanks require maintenance between batches. The biodiesel storage tank

should not possess more than 20 gallons to prevent overflow when the new cycle

completes. The wastewater disposal line must flow to a contained area so that the soap

and water mixture from the washing cycles does not interfere with the natural water flow

or contents.

The waste oil tank must hold precisely 20 gallons in order to produce a 20 gallon yield.

Similarly, the dual tank assembly containing the methanol and second mixing tanks

requires 74.8 grams of Sodium Hydroxide in the bottom tank and 4 gallons of Methanol

in the top tank. When working with these chemicals please take the appropriate safety

precautions being sure to wear protective gloves, safety goggles, long sleeve shirts, and

long pants. For further information regarding the handling of the chemicals in the

system, be sure to read the material safety data sheets (MSDS) found later in this booklet.

Operators should also check washing and mixing tanks for sediment build-up and proper

drainage of the previous batch before proceeding. In addition, users need to check the

integrity of the lines between the tanks to ensure there are no clogs or dissolving

components.

After completing this examination and ensuring that all the components comply with the

stated parameters depress the black button in the control box. While the system runs

check to make sure that the fluids transfer properly with the valves opening at the proper

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times. Another important element that operators should check for is the presence of leaks

from the mixing tank or the washing tank. It is important to maintain the seals on both

tanks for full efficiency. Once the process is complete, remove the biodiesel1 from

storage for use and begin a new process2.

Section 2 – Mechanical Maintenance In addition to the standard checklist for every batch, each month the following list

requires attention:

1) Flush system using a hot water and soap solution

2) Properly Dispose of accumulated glycerine

3) Inspect hoses thoroughly for signs of wear or leaks

4) Inspect structure for rotting and/or cracks

5) Ensure that the belt on the large mixing tank is in good condition

6) Grease bearing at the top end of the mixing shaft

7) Clean and remove any accumulation on float switches and shafts

If users complete this list each month on top of the checks for every batch, the

system will continue to run at peak efficiency.

Section 3 – Electrical Maintenance

The following flow charts represent the control system for the mix cycle and the wash

cycle while the program code on the pages after them relays the full text of the control

1 Note that once a month a sample of the biodiesel should be taken to the chemistry lab for testing to make sure that it complies with ASTM standards. 2 Biodiesel process needs to run twice a week in order to produce the 40 gallon yield it was designed for. While it can run three times a week to produce 60 gallons the choice to do this or not depends on the owner of the facility, ie Messiah College.

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program. If the electrical components malfunction, please refer to these documents for

the debugging process.

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*************************** * Data Initiation Sequence* *************************** * 68HC11 Registers Reg EQU $1000 PIOC EQU $1002 PortC EQU $1003 PortB EQU $1004 PortCL EQU $1005 DDRC EQU $1007 ADCTL EQU $1030 ADR1 EQU $1031 ADOP EQU $1039 TIC1 EQU $1010 TFLG2 EQU $1025 TMSK2 EQU $1024 * Masks Bit0 EQU %00000001 Bit1 EQU %00000010 Bit2 EQU %00000100 Bit3 EQU %00001000 Bit4 EQU %00010000 Bit5 EQU %00100000 Bit6 EQU %01000000 Bit7 EQU %10000000 * Data Section ORG $100 * Flags Flag1 RMB 1 Flag2 RMB 1 Flag3 RMB 1 Flag4 RMB 1 Flag5 RMB 1 Flag6 RMB 1 Flag7 RMB 1 * Counters Mem1 RMB 1 Mem2 RMB 1 Mem3 RMB 1 Mem4 RMB 1 Mem5 RMB 1 Mem6 RMB 1 Mem7 RMB 1 Mem8 RMB 1 Wnum RMB 1 Counter RMB 1 * Defining ISR ORG $00D1 00D1 75 20 FDB $7520 ********************************* *Program Initialization Sequence* ********************************* Start Init ORG $7000 *Set I/O on PortC 7000 86 3C LDAA #%00111100 0 - in, 1 - out 7002 B7 10 07 STAA DDRC

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*Set up PIOC 7005 86 02 LDAA #$02 Enable STAF interrupts 7007 B7 10 02 STAA PIOC *Set up A/D converter 700A 86 30 LDAA #%00110000 Enable continual scan 700C B7 10 30 STAA ADCTL zero *Initialize Stack 700F 8E 00 FF LDS #$00FF *Initialize timer overflow interrupt 7012 86 80 LDAA #%10000000 7014 B7 10 24 STAA TMSK2 *Initialize Flags 7017 C6 01 LDAB #1 7019 F7 01 03 STAB Flag4 701C 7F 01 00 CLR Flag1 701F 7F 01 01 CLR Flag2 7022 7F 01 02 CLR Flag3 7025 7F 01 04 CLR Flag5 7028 7F 01 05 CLR Flag6 702B 7F 01 06 CLR Flag7 702E 7F 01 0E CLR Mem8 7031 86 C0 LDAA #$C0 7033 B7 01 07 STAA Mem1 7036 B7 01 08 STAA Mem2 7039 B7 01 09 STAA Mem3 703C B7 01 0C STAA Mem6 703F B7 01 0D STAA Mem7 7042 86 00 LDAA #0 7044 B7 01 0A STAA Mem4 7047 B7 01 0B STAA Mem5 704A 7F 01 0F CLR Wnum 704D 7F 01 10 CLR Counter *Clear Ports 7050 7F 10 00 CLR Reg 7053 7F 10 04 CLR PortB 7056 7F 10 03 CLR PortC *Clear accumulators and counters 7059 4F CLRA 705A 5F CLRB 705B CE 00 00 LDX #0 705E 18 CE 00 00 LDY #0 * Turn on interrupt sys 7062 0E CLI *********** *Mix Cycle* *********** *Shut Off Sequence 7063 86 80 SOT LDAA #%10000000 Test shutoff switch 7065 B4 10 03 ANDA PortC 7068 80 80 SUBA #%10000000 706A 27 03 BEQ SO 706C 7E 70 72 JMP Timer 706F 7E 75 30 SO JMP Shutoff 7072 B6 10 02 Timer LDAA PIOC 7075 84 80 ANDA #%10000000 7077 27 03 BEQ MT1 7079 BD 75 10 JSR ISR

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*Mix Tests 707C 86 02 MT1 LDAA #%10 MTS1 off? 707E B4 10 00 ANDA Reg 7081 80 02 SUBA #2 7083 27 23 BEQ MT2 7085 86 01 LDAA #%1 HTS on? 7087 B4 10 00 ANDA Reg 708A 80 01 SUBA #1 708C 27 0A BEQ JUMP1 708E 86 01 LDAA #1 F1 active? 7090 B5 01 00 BITA Flag1 7093 26 03 BNE JUMP1 7095 7E 70 A8 JMP MT2 7098 7E 71 C6 JUMP1 JMP MP1 709B 86 84 MT1A LDAA #%10000100 G-Drain and Pump3 off? 709D B4 10 04 ANDA PortB 70A0 26 03 BNE JUMP2 70A2 7E 71 C6 JMP MP1 70A5 7E 70 A8 JUMP2 JMP MT2 70A8 86 01 MT2 LDAA #01 Flag 3 on? 70AA B0 01 02 SUBA Flag3 70AD 27 03 BEQ J5 70AF 7E 71 C3 JMP MFIN 70B2 86 02 J5 LDAA #2 MTS1 on? 70B4 B4 10 00 ANDA Reg 70B7 80 00 SUBA #0 70B9 26 03 BNE J6 70BB 7E 71 5A JMP MT7 70BE 86 01 J6 LDAA #1 Flag1 high? 70C0 B5 01 00 BITA Flag1 70C3 27 0F BEQ MT3 70C5 86 01 LDAA #1 Timer < 5m = 1p? 70C7 8F XGDX 70C8 F7 01 07 STAB Mem1 70CB 8F XGDX 70CC B0 01 07 SUBA Mem1 70CF 27 03 BEQ MT3 70D1 7E 71 E0 JMP MP2 70D4 86 01 MT3 LDAA #1 Timer = 5m = 1p? 70D6 8F XGDX 70D7 F7 01 07 STAB Mem1 70DA 8F XGDX 70DB B0 01 07 SUBA Mem1 70DE 26 03 BNE J4 70E0 7E 71 E8 JMP MP3 70E3 86 01 J4 LDAA #1 Timer < 5m = 1p? 70E5 8F XGDX 70E6 F7 01 07 STAB Mem1 70E9 8F XGDX 70EA B0 01 07 SUBA Mem1 70ED 22 0F BHI MT4 70EF 86 06 LDAA #6 Timer > 35m = 7p? 70F1 8F XGDX 70F2 F7 01 07 STAB Mem1 70F5 8F XGDX 70F6 B0 01 07 SUBA Mem1 70F9 25 03 BLO MT4

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70FB 7E 71 E8 JMP MP3 70FE 8F MT4 XGDX Timer > 35m = 7p? 70FF F7 01 07 STAB Mem1 7102 8F XGDX 7103 86 06 LDAA #6 7105 B0 01 07 SUBA Mem1 7108 22 11 BHI MT5 710A 86 01 LDAA #1 Flag2 low? 710C B0 01 01 SUBA Flag2 710F 27 0A BEQ MT5 7111 B6 10 31 LDAA ADR1 Is temp > 50 C? 7114 80 05 SUBA #%00000101 assuming 00000101 = 50C 7116 25 03 BLO MT5 7118 7E 71 F3 JMP MP4 711B 86 0B MT5 LDAA #11 Mixing for 60m = 12p? 711D BB 01 08 ADDA Mem2 7120 8F XGDX 7121 F7 01 07 STAB Mem1 7124 8F XGDX 7125 B0 01 07 SUBA Mem1 7128 25 0C BLO MT6 712A 86 02 LDAA #02 Valve 2 open? 712C B4 10 04 ANDA PortB 712F 80 00 SUBA #0 7131 27 03 BEQ MT6 7133 7E 72 05 JMP MP5 7136 86 0B MT6 LDAA #11 Is mixing time done? 7138 BB 01 08 ADDA Mem2 713B 8F XGDX 713C F7 01 07 STAB Mem1 713F 8F XGDX 7140 B0 01 07 SUBA Mem1 7143 22 15 BHI MT7 7145 B6 01 0E LDAA Mem8 Mem8 > Timer? 7148 B0 01 07 SUBA Mem1 714B 22 0D BHI MT7 714D 86 5F LDAA #95 Within settling time? 714F BB 01 08 ADDA Mem2 480m = 96p 7152 B0 01 07 SUBA Mem1 7155 25 03 BLO MT7 7157 7E 72 08 JMP MP6 715A 86 01 MT7 LDAA #1 Is F7 low? 715C B0 01 06 SUBA Flag7 715F 27 62 BEQ MFIN 7161 86 01 LDAA #01 F2 High? 7163 B0 01 01 SUBA Flag2 7166 26 5B BNE MFIN 7168 86 5F LDAA #95 Done settling? 716A BB 01 08 ADDA Mem2 Mem8 > 480m = 96p? 716D B0 01 0E SUBA Mem8 7170 22 0A BHI MT8 7172 86 01 LDAA #1 Flag 6 low? 7174 B0 01 05 SUBA Flag6 7177 27 03 BEQ MT8 7179 7E 72 18 JMP MP7 717C 86 01 MT8 LDAA #1 Flag 6 high? 717E B0 01 05 SUBA Flag6

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7181 26 12 BNE MT9 7183 86 02 LDAA #2 BioD draining for 15m = 3p? 7185 BB 01 09 ADDA Mem3 7188 8F XGDX 7189 F7 01 07 STAB Mem1 718C 8F XGDX 718D B0 01 07 SUBA Mem1 7190 25 03 BLO MT9 7192 7E 72 41 JMP MP8 7195 86 03 MT9 LDAA #3 BioD done draining? 7197 BB 01 09 ADDA Mem3 719A 8F XGDX 719B F7 01 07 STAB Mem1 719E 8F XGDX 719F B0 01 07 SUBA Mem1 71A2 22 0D BHI MT10 71A4 86 05 LDAA #5 71A6 BB 01 09 ADDA Mem3 71A9 B0 01 07 SUBA Mem1 71AC 25 03 BLO MT10 71AE 7E 72 49 JMP MP9 71B1 86 05 MT10 LDAA #5 Process finished? 71B3 BB 01 09 ADDA Mem3 71B6 8F XGDX 71B7 F7 01 07 STAB Mem1 71BA 8F XGDX 71BB B0 01 07 SUBA Mem1 71BE 22 03 BHI MFIN 71C0 7E 72 51 JMP MP10 71C3 7E 73 08 MFIN JMP WT1 71C6 86 01 MP1 LDAA #1 Set F3 High 71C8 B7 01 02 STAA Flag3 71CB 86 20 LDAA #%00100000 Pump1 on 71CD B7 10 04 STAA PortB 71D0 8B 10 ADDA #%00010000 Motor and heater on 71D2 B7 10 00 StAA Reg 71D5 86 01 LDAA #1 F1 high 71D7 B7 01 00 STAA Flag1 71DA CE 00 00 LDX #0 Reset timer 71DD 7E 71 C3 JMP MFIN 71E0 86 41 MP2 LDAA #%01000001 Pump1 off, Pump2 on, Valve1 open 71E2 B7 10 04 STAA PortB 71E5 7E 74 00 JMP TCHECK Check and adjust temp 71E8 86 00 MP3 LDAA #0 Pump2 off, Valve1 close, F1 low 71EA B7 10 04 STAA PortB 71ED B7 01 00 STAA Flag1 71F0 7E 74 00 JMP TCHECK check temperature 71F3 86 02 MP4 LDAA #%10 open Mix2 drain (valve2) 71F5 B7 10 04 STAA PortB 71F8 8F XGDX 71F9 F7 01 08 STAB Mem2 71FC 8F XGDX record time 71FD 86 01 LDAA #1 Set F2 high 71FF B7 01 01 STAA Flag2 7202 7E 74 00 JMP TCHECK check temperature

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7205 7E 74 00 MP5 JMP TCHECK check temperature 7208 86 00 MP6 LDAA #0 heater, mixer off 720A B7 10 00 STAA Reg 720D B7 10 04 STAA PortB close valve 2 7210 8F XGDX 7211 F7 01 0E STAB Mem8 Store Timer 7214 8F XGDX 7215 7E 71 C3 JMP MFIN 7218 86 04 MP7 LDAA #%100 open valve 3 721A B7 10 04 STAA PortB 721D 86 01 LDAA #1 721F B7 01 05 STAA Flag6 7222 B7 01 04 STAA Flag5 7225 86 00 LDAA #0 7227 B7 01 10 STAA Counter 722A B6 01 10 Loop LDAA Counter 722D 80 30 SUBA #$30 722F 22 03 BHI L1 7231 7E 72 2A JMP Loop 7234 86 00 L1 LDAA #0 7236 B7 10 04 STAA PortB 7239 8F XGDX 723A F7 01 09 STAB Mem3 723D 8F XGDX 723E 7E 71 C3 JMP MFin 7241 86 80 MP8 LDAA #%10000000 close valve 3 7243 B7 10 04 STAA PortB Pump3 on 7246 7E 71 C3 JMP MFIN 7249 86 04 MP9 LDAA #%100 open valve3 724B B7 10 04 STAA PortB pump3 off 724E 7E 71 C3 JMP MFIN 7251 7F 10 00 MP10 CLR REG Clear ports 7254 7F 10 04 CLR PORTB 7257 86 01 LDAA #1 Set F5 High 7259 B7 01 06 STAA Flag7 725C DE 00 LDX 0 Reset timer 725E 7F 01 00 CLR Flag1 Set flags low 7261 7F 01 01 CLR Flag2 7264 7F 01 05 CLR Flag6 7267 7F 01 0E CLR Mem8 726A 86 C0 LDAA #$C0 726C B7 01 07 STAA Mem1 726F B7 01 08 STAA Mem2 7272 B7 01 09 STAA Mem3 7275 7E 71 C3 JMP MFIN 7278 7F 10 03 WP1 CLR PortC 727B 18 DE 00 LDY 0 Reset timer 727E C6 00 LDAB #0 Set F4 low 7280 F7 01 03 STAB Flag4 7283 7E 73 FD JMP WFIN 7286 C6 04 WP2 LDAB #%100 open water valve 7288 F7 10 03 STAB PortC 728B 18 8F XGDY 728D F7 01 0B STAB Mem5 7290 18 8F XGDY record time 7292 7E 73 FD JMP WFIN 7295 C6 20 WP3 LDAB #%100000 water vlave close, bubles on

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7297 F7 10 03 STAB PortC 729A 7E 73 FD JMP WFIN 729D C6 00 WP4 LDAB #0 bubbles off 729F F7 10 03 STAB PortC 72A2 7E 73 FD JMP WFIN 72A5 C6 08 WP5 LDAB #%1000 open water drain 72A7 F7 10 03 STAB PortC 72AA 18 8F XGDY 72AC F7 01 0C STAB Mem6 72AF 18 8F XGDY record time 72B1 C6 01 LDAB #1 F4 high 72B3 F7 01 03 STAB Flag4 72B6 7E 73 FD JMP WFIN 72B9 C6 00 WP7 LDAB #0 Close H2O Drain 72BB F7 10 03 STAB PortC 72BE 7C 01 0F INC Wnum increment Wnum 72C1 C6 00 LDAB #0 F4 low 72C3 F7 01 03 STAB Flag4 72C6 18 CE 00 00 LDY #0 reset timer 72CA 7F 01 0B CLR Mem5 reset Mem5 72CD 7E 73 FD JMP WFIN 72D0 C6 10 WP8 LDAB #%10000 close water drain 72D2 F7 10 03 STAB PortC open BioD drain 72D5 7E 73 FD JMP WFIN 72D8 C6 28 WP9 LDAB #%101000 close BioD drain 72DA F7 10 03 STAB PortC open water drain open water drain 72DD 7E 73 FD JMP WFIN 72E0 7F 10 03 WP13 CLR PortC Clear PortC 72E3 18 CE 00 00 LDY #0 reset timer 72E7 C6 01 LDAB #1 F4 high 72E9 F7 01 03 STAB Flag4 72EC C6 00 LDAB #0 clear timers 72EE F7 01 0A STAB Mem4 72F1 F7 01 0B STAB Mem5 72F4 F7 01 0D STAB Mem7 72F7 F7 01 04 STAB Flag5 72FA F7 01 06 STAB Flag7 72FD F7 01 0F STAB Wnum reset Wash number 7300 C6 C0 LDAB #$c0 7302 F7 01 0C STAB Mem6 7305 7E 73 FD JMP WFIN 7308 C6 01 WT1 LDAB #1 Is F5 high? 730A F0 01 04 SUBB Flag5 730D 27 03 BEQ WJ1 730F 7E 73 FD JMP WFIN 7312 C6 80 WJ1 LDAB #%10000000 Pump 3 on? 7314 F4 10 04 ANDB PortB 7317 C0 80 SUBB #%10000000 7319 26 03 BNE JUMP3 731B 7E 72 78 JMP WP1 731E 7E 73 21 JUMP3 JMP WT2 7321 C6 04 WT2 LDAB #%100 WTS1 off? 7323 F4 10 00 ANDB Reg 7326 C0 04 SUBB #%100 7328 27 0A BEQ WT3 732A F6 01 03 LDAB Flag4 Flag 4 low?

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732D C0 01 SUBB #1 732F 27 03 BEQ WT3 7331 7E 72 86 JMP WP2 7334 F6 01 03 WT3 LDAB Flag4 Flag 4 low? 7337 C0 01 SUBB #1 7339 27 14 BEQ WT4 733B 18 8F XGDY 733D F7 01 0A STAB Mem4 7340 18 8F XGDY 7342 F6 01 0B LDAB Mem5 timer < Mem5 + 6p? 7345 CB 05 ADDB #5 7347 F0 01 0A SUBB Mem4 734A 25 03 BLO WT4 734C 7E 72 95 JMP WP3 734F F6 01 03 WT4 LDAB Flag4 Flag 4 low? 7352 C0 01 SUBB #1 7354 27 1E BEQ WT5 7356 18 8F XGDY 7358 F7 01 0A STAB Mem4 735B 18 8F XGDY Done mixing? 735D F6 01 0B LDAB Mem5 timer > Mem5 + 6p? 7360 CB 05 ADDB #5 7362 F0 01 0A SUBB Mem4 7365 22 0D BHI WT5 7367 F6 01 0B LDAB Mem5 Settling Range? 736A CB 7E ADDB #126 timer < Mem5 + 126p? 736C F0 01 0A SUBB Mem4 736F 25 03 BLO WT5 7371 7E 72 9D JMP WP4 7374 18 8F WT5 XGDY 7376 F7 01 0A STAB Mem4 Store timer in Mem4 7379 18 8F XGDY 737B F6 01 0C LDAB Mem6 Timer < Mem6 + 2p? 737E CB 02 ADDB #2 7380 F0 01 0A SUBB Mem4 7383 25 16 BLO WT6 7385 F6 01 0B LDAB Mem5 timer > Mem5 + 126p? 7388 CB 7E ADDB #126 738A F0 01 0A SUBB Mem4 738D 22 0C BHI WT6 738F C6 40 LDAB #%1000000 WTS2 Low? 7391 F4 10 03 ANDB PortC 7394 C0 40 SUBB #%1000000 7396 27 03 BEQ WT6 7398 7E 72 A5 JMP WP5 739B C6 03 WT6 LDAB #3 Finished with 3rd Wash? 739D F0 01 0F SUBB Wnum 73A0 27 15 BEQ WT8 73A2 7E 73 A5 JMP WT7 73A5 F6 01 0A WT7 LDAB Mem4 timer <> 0? 73A8 27 0D BEQ WT8 73AA F6 01 03 LDAB Flag4 F4 high? 73AD C0 01 SUBB #1 73AF 26 03 BNE JUMP4 73B1 7E 72 B9 JMP WP7 73B4 7E 73 FD JUMP4 JMP WFIN 73B7 18 8F WT8 XGDY

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73B9 F7 01 0A STAB Mem4 73BC 18 8F XGDY timer < mem6 + 1p? 73BE F6 01 0C LDAB Mem6 73C1 CB 01 ADDB #1 73C3 F0 01 0A SUBB Mem4 73C6 25 03 BLO WT9 73C8 7E 72 D0 JMP WP8 73CB 18 8F WT9 XGDY 73CD F7 01 0A STAB Mem4 73D0 18 8F XGDY timer > mem6 + 1p? 73D2 F6 01 0C LDAB Mem6 73D5 CB 01 ADDB #1 73D7 F0 01 0A SUBB Mem4 73DA 22 0D BHI WT13 73DC F6 01 0C LDAB Mem6 timer < mem6 + 1p? 73DF CB 01 ADDB #1 73E1 F0 01 0A SUBB Mem4 73E4 25 03 BLO WT13 73E6 7E 72 D8 JMP WP9 73E9 18 8F WT13 XGDY 73EB F7 01 0A STAB Mem4 73EE 18 8F XGDY timer > mem6 + 4p? 73F0 F6 01 0C LDAB Mem6 73F3 CB 04 ADDB #4 73F5 F0 01 0A SUBB Mem4 73F8 22 03 BHI WFIN 73FA 7E 72 E0 JMP WP13 73FD 7E 70 63 WFIN JMP SOT 7400 B6 10 31 TCHECK LDAA ADR1 Is temp > 50 C? 7403 80 05 SUBA #%00000101 assuming 00000101 = 50C 7405 25 03 BLO HEAT 7407 7E 74 15 JMP COOL 740A B6 10 00 HEAT LDAA Reg turn on the heater 740D 8A 20 ORAA #%00100000 740F B7 10 00 STAA Reg 7412 7E 71 C3 JMP MFIN 7415 B6 10 00 COOL LDAA Reg turn off the heater 7418 84 DF ANDA #%11011111 741A B7 10 00 STAA Reg 741D 7E 71 C3 JMP MFIN ORG $7510 7510 B6 10 02 ISR LDAA PIOC Reset the STAF flag 7513 B6 10 05 LDAA PORTCL 7516 08 INX Increment X on Stack 7517 18 08 INY Increment Y on Stack 7519 39 RTS Return to main prog. ORG $7520 7520 0F TOFISR SEI 7521 86 80 LDAA #%10000000 Store 1 to clear flag 7523 B7 10 25 STAA TFLG2 7526 7C 01 10 INC Counter 7529 3B RTI ORG $7530 7530 7F 10 00 Shutoff CLR Reg

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7533 7F 10 04 CLR PortB 7536 7F 10 03 CLR PortC 7539 86 40 LDAA #%1000000 753B B7 10 00 STAA Reg 753E 7E 75 30 JMP Shutoff END Symbol Table MFIN 71C3 MT10 71B1 PORTCL 1005 MT1A 709B WJ1 7312 WP13 72E0 COUNTER 0110 SOT 7063 INIT 7000 ISR 7510 TMSK2 1024 MP1 71C6 MP2 71E0 MP3 71E8 MP4 71F3 MP5 7205 MP6 7208 MP7 7218 MP8 7241 MP9 7249 REG 1000 TOFISR 7520 PIOC 1002 J4 70E3 J5 70B2 J6 70BE ADCTL 1030 TFLG2 1025 WFIN 73FD WT13 73E9 WP1 7278 L1 7234 WP2 7286 SHUTOFF 7530 WP3 7295 WP4 729D WP5 72A5 WP7 72B9 WP8 72D0 WP9 72D8 TCHECK 7400 MT1 707C MT2 70A8 MT3 70D4 MT4 70FE MT5 711B MT6 7136 MT7 715A

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MT8 717C MT9 7195 HEAT 740A START 00D3 ADOP 1039 WNUM 010F WT1 7308 WT2 7321 WT3 7334 WT4 734F WT5 7374 WT6 739B WT7 73A5 WT8 73B7 WT9 73CB ADR1 1031 TIMER 7072 MP10 7251 PORTB 1004 PORTC 1003 BIT0 0001 BIT1 0002 BIT2 0004 BIT3 0008 BIT4 0010 BIT5 0020 BIT6 0040 BIT7 0080 DDRC 1007 JUMP1 7098 JUMP2 70A5 JUMP3 731E JUMP4 73B4 COOL 7415 MEM1 0107 MEM2 0108 MEM3 0109 MEM4 010A MEM5 010B MEM6 010C MEM7 010D MEM8 010E LOOP 722A SO 706F FLAG1 0100 FLAG2 0101 FLAG3 0102 FLAG4 0103 TIC1 1010 FLAG5 0104 FLAG6 0105 FLAG7