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PHANTOMDigital Handheld Communication and Navigation Device

General System Design Freescale 9s12xep100 microcontroller

50 MHz bus frequency Chip Resources

3 of 6 SCI Ports Two interrupt driven

Wake-Up Interrupts on Port H and Port J (Key + RF) Time Channel 6 Interrupt (Used by Kernel)

Memory Usage ROM – 21.6kB of 48kB (up to 1MB paged) RAM – 8kB of 8kB (up to 64kB paged) EEPROM – 500B of 2kB (up to 4kB paged)

Kernel Design uC/OS-II – A real-time preemptive

multitasking kernel Tick Period – 1ms 3+2Tasks 2 ISRs 4 Flags 1 Mutex

Task/ISR TimingTask/ISR Priorit

yPerio

d(avg)

Period(min)

Behavior

Execution Time (avg)

Execution Time (max)

CPULoad(avg)

CPU Load (max)

RFrxISR - 60sec* 0.8ms Sporadic 2µs * 2µs * ~0.0%

0.25%

GPSrxISR - 30sec* 1.7ms Sporadic 2µs 2µs ~0.0%

0.12%

StartTask 4 - - Run Once

2sec 2sec - -

OS_TIMER_TIMER

5 1ms 1ms Periodic 0.5µs 0.5µs 0.05% 0.05%

SysTask (newKey)

6 120sec

16ms Sporadic 7.1ms* 7.1ms* ~0.0%

44.3%

(newSec)

1sec 1sec Periodic 5ms* 5ms* 0.5% 0.5%

(newMsg)

60sec 162.4ms Sporadic 7.3ms* 7.3ms* 0.02% 4.5%

(newGPS)

30sec 61.2ms Sporadic 7.2ms* 7.2ms* 0.02% 11.8%

KeyTask 7 8ms 8ms Periodic 8µs * 10µs 0.1% 0.13%

ClockTask 8 1sec 1sec Periodic 1µs * 1µs ~0.0%

~0.0%

*Estimated**Maximum load should be considered average load because system will be sleeping during “average” load conditions.

Maximum CPU Load: 44.85%

Average CPU Load: ~0.7%**

Start Task Initializes Keypad, GPS, Clock, RF, and

LCD hardware Creates the other tasks Period: Run once Execution time: ~2sec

RFrxISR Triggered by RDRF (Read Data Register

Full) flag on RF SCI port Copies incoming byte to buffer and

exits When end of message is detected or

the buffer is full, posts a flag notifying SysTask

Period: 0.8ms (time in between bytes at 9600bps), Behavior is sporadic

Execution time: 2µs

GPSrxISR Virtually identical to RFrxISR Triggered by RDRF on GPS SCI port Copies incoming byte to buffer and

exits When end of message is detected or

the buffer is full, posts a flag notifying SysTask

Period: 1.7ms (time in between bytes at 4800bps)

Execution time: 2µs

KeyTask Scans keypad to detect and debounce

user key presses Posts a flag notifying SysTask of user

inputted key Period: 8ms (periodic) Execution time:

Maximum: 10µs Average: 8µs (estimated)

ClockTask Uses OS Delay to count current time of

day and date Posts flag notifying SysTask that one

second has elapsed Period: 1s (periodic) Execution time: 1µs

SysTask Runs on New RF Message, New GPS Message, New Key

Press and New Second events Processes user input, including keypad multitap Processes RF and GPS data Provides the Graphical User Interface (GUI) State machine structure to react to events and display

correct graphical output for the event type and current user screen

Monitors power status and controls system power cycle Saves user settings in EEPROM Provides software tools to user

SysTask (GPS) Parses and interperets NMEA 0183 message

streamed from GPS hardware Location data is updated

Period: Minimum: 61.2ms Average: 30sec

Execution time: Parsing and translating: 200µs Maximum: 7.2ms (estimated) Average: 7.2ms (estimated)

SysTask (Messaging) Four primary functions: interpret received messages, transmit outgoing

messages, manage message cryptography, and conduct Medium Access Control (MAC)

Incoming messages are processed when newMsg flag is posted by RFrxISR. The header is examined to determine if the system is the intended recipient. If it is, an ACK message is transmitted to the sender. No ACK will be transmitted for “Broadcast-All” messages. Message content will be decrypted using aes256 module, and message data will be ready to use.

For outgoing messages, message is encrypted, headers are added, and message is sent to the LN96 for transmission

Period: Minimum: 162.4ms Average: 60sec

Execution time: Parsing and translating: 300µs (estimated) Maximum: 7.3ms (estimated) Average: 7.3ms (estimated)

SysTask (User Input) When the newKey flag is posted by KeyTask, SysTask

will retrieve that key and interpret the key’s meaning based on the current state and cursor location

Multitap function may be used depending on current state

Period: Minimum: 16ms Average: 120sec

Execution time: Maximum: 7.1ms (estimated) Average: 7.1ms (estimated)

SysTask (Clock) When newSec flag is posted by

ClockTask, SysTask will update the time on the LCD if appropriate

A mutex will be used to control access to the date-time information

Period: 1 sec Execution time: 5ms (estimated)

Task/Module RelationshipsSystemTask*main.c LN96.c

LCD.c aes256.c

EEPROM.c *messaging.c

power.c random.c

tools.c multitap.c

gps.c 9s12xep100.c

*Module where task code exists.

KeyTask

*ucoskey.c

ClockTask

*clock.c

Modules and LibrariesModule/Library

Tasks Public Functions and Data

Estimated ROM/RAM

main.c StartTask,SysTask

settingsData 2500b/4kb

LCD.c lcd_init(),lcd_powerdown()lcd_setbgcolor(),lcd_display()lcd_backlight(),lcd_putchar()lcd_setfontsize(),lcd_putstrg()lcd_getfontsize(),lcd_clear()lcd_putimage(),lcd_getcolor()lcd_movecursor()lcd_setcolor(),lcd_eraseline() lcd_disptime(),lcd_getcursor()lcd_txtopaque()

780b/10b

Modules and LibrariesModule/Library

Tasks Public Functions and Data

Estimated ROM/RAM

EEPROM.cAdapted from Todd Morton

EESectModify(),EESectErase()EEWordWrite

400b/10b

power.c Sleep(),Stop(),Powerdown()

200b/10b

tools.c gridFind() 400b/300b

multitap.c getMultiTap() 1800b/200b

9s12xep100start.cAdapted from Todd Morton

_Startup() 80b/0b

uCOSkey.cAdapted from Todd Morton

KeyTask KeyPend(),KeyInit() 400b/70b

gps.c GPSrxISR gpsDatagps_getRMC(),gps_getGSV()gps_init(),gps_setqueryrate()

1100b/400b

Modules and LibrariesModule/Library

Tasks Public Functions and Data

Estimated ROM/RAM

clock.c ClockTask TimeBuffer 120b/70b

LN96.c RFrxISR rf_init(),rf_write(),rf_reset() 500b/10b

aes256.cCopyright (c) 2007-2009 Ilya O. Levin

aes256_init()aes256_done()aes256_encrypt_ecb()aes256_decrypt_ecb()

1400b/500b

messaging.c msgData,rfMsgBuffersendMsg()

2000b/800b

random.c getRand() 500b/100b

Modules and LibrariesModule/Library

Tasks Public Functions and Data

Estimated ROM/RAM

uC/OS-II(c) Copyright 1992-2007, Jean J. Labrosse

OS_TASK_TIMER

See uC/OS-II Documentation

2400b/1500b

Math.cISO C Standard Library

undetermined undetermined

String.cISO C Standard Library

undetermined undetermined

STDIO.cISO C Standard Library

undetermined undetermined

STDLIB.cISO C Standard Library

undetermined undetermined ~7k ROMfor C Libraries

Total: 21.6kb ROM8kb RAM

GPS Communication

RF Communication

User I/O

Date/Time Tracking

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Questions? Kernel Choice Tasks

StartTask RFrxISR GPSrxISr SysTask KeyTask ClockTask

Data Control Medium Access Control GPS Communication Power Management Memory Usage ?

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