Assurance of Programmable Logic Devices

NASA Glenn Research Center

Kalynnda Berens, SAICCoursework: Jacqueline Somos, SAIC

SAS 2004 2

Mission Success Starts With Safety

The Problems:

Programmable Logic Controllers (PLCs) are “programmed” by engineers, often without Software Assurance oversight. PLCs are used in Wind Tunnels and other facilities

Programmable Logic Devices (PLDs) are hybrids PLDs (FPGA, ASIC, etc.) are used in ground and flight systems PLDs are similar to software, with many of the same problems PL devices are ultimately “hardware”, but programmed like

software. Current assurance activities may not be adequate for the

complexity of these devices.

SAS 2004 3

Mission Success Starts With Safety

Our approach Year 1:

Distribute surveys to determine where and how Programmable Logic is used at NASA and how it is being assured.

Year 2: Document practices outside of NASA for assuring Programmable

Logic. Compare the assurance practices of NASA with those of other

industries (especially high risk industries such as nuclear and medical).

Issue Paper

Year 3: Present best industry practices in the form of a series of courses and

in a guidebook.

SAS 2004 4

Mission Success Starts With Safety

Importance and Benefits Awareness

Where PLDs and PLCs are used

Current assurance activities

Comparison NASA practices with high

risk industry practices Will new practices improve

safety?

PLCs and PLDs for software assurance personnel

Process assurance for hardware QA

TRAININGTRAINING

SAS 2004 5

Mission Success Starts With Safety

Relevance to NASA PLCs and PLDs are widely used at NASA

Flight equipment for Shuttle and Station Small satellite technology development Centrifuge Control Wind tunnel

Future trends indicate that PLDs will be used more often and in more complex applications. May replace software in some systems Complexity means testing is not enough!

Can NASA Software Assurance personnel adequately verify PLCs and PLDs?

Can NASA Quality Assurance personnel?

SAS 2004 6

Mission Success Starts With Safety

Accomplishments Survey of NASA usage and assurance for

PLCs and PLDs Industry/military/government Best Practices Issue Paper – summary and

recommendations PLCs for SA course

almost complete

SAS 2004 7

Mission Success Starts With Safety

Next Steps Create PLD and Process Assurance

courses Evaluate/Review courses

We’re looking for interested reviewers Come see the demo!

Submit courses to SOLAR Publish information in a guidebook

format