Major Software Components

• Basic Watch Functions
• User Interface
• Calibration
• Telemetry and Detection

The following document describes the function and requirements of the above high-level components. The work required to complete each enumerated software compenent is expressed in lines of code (LOC). Estimates are given for the prototyping software (implemented on a PC in a high-level language). It is expected that the finished prototyping software, produced in C, will incur 25% additional manhours to be ported to the microprocessor specified by our hardware design. This document provides only general design guidelines, and part of the of the software implementation will involve a more rigorous application of the principles of software design and engineering.

Basic Watch Functions
The basic watch functionality will provided as part of the hardware design, supplied by Full Field Industrial Ltd. For the purposes of the associated hardware, this design should include, at least in part, the following functions:

• Chronograph
• Multiple alarms

User Interface
The user interface will rely upon the hardware design. Assuming a standard watch configuration featuring four to five input buttons, the sleep detection functionality of the user interface will require a number of inputs. The user interface software will need to, via the watch's LCD, prompt the user for the following inputs, accept input via watch buttons, and save these selections to registers in the watch.

1. Detection sensitivity
1. Wrist activity sensitivity
2. Base heart rate sensitivity
3. Heart rate change sensitivity
2. Activation intervals
3. Timed activation, deactivation
4. Wake method
1. Vibration
2. Audible alarm
1. Volume

Estimated LOC: 500

Calibration
In order to make an accurate prediction of sleep, the watch will need to compare the current heart rate against an individual's resting heart rate. The watch will include a heart rate calibration routine which will calculate resting heart rate and monitor heart changes over a sleeping calibration interval. These data will be stored in watch registers and used by the detection algorithm.

1. Monitor heart rate over interval
1. Log drops in heart rate over sub-intervals
2. Distinguish initial sleep stage from subsequent stages by rate change
3. Determine resting heart rate relative to first sleep stage

Estimated LOC: 800

Telemetry and Detection
The hardware designs provides both a digital plethysmograph and accelerometer to monitor pulse and wrist movement. When detection is active, this software module monitors these inputs and activates an alert mechanism accordingly.

1. Wrist-activity, accelerometer
1. Detect sustained inactivity
2. Pulse, plethysmograph
1. Detect below-basline heart rate
2. Detect drop in heart rate
3. Detection
1. Intersection of wrist-activity and pulse

Estimated LOC: 1500

Prototyping Hardware
To allow for telemetry and detection prototyping, three to five computer workstations will be required with a peripheral plethysmograph. J&J Engineering's C2-GP bio-feedback device can monitor heart rate and heart rate variability, and communicates through a standard RS-232 interface. This unit is priced at $1,995.

Component Times
Assuming a well-qualified programmer writes 20 LOC per day:

User Interface	25 days
Calibration	40 days
Telemetry and Detection	75 days
Porting	30 days
Total	170 days

Component and Personnel Costs
In order to complete the software prototyping and design within two months, three programmers will be required:

Programmers (3), 60 days	$60,000
Software Engineer	$30,000
Hardware Consultant	$10,000
Bio-feedback Hardware	$2,000
Development Workstations (5)	$10,000
Total	$67,000