Digital Handheld Communication and Navigation Device

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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)

uC/OS-II – A real-time preemptive multitasking kernel Tick Period – 1ms 3+2Tasks 2 ISRs 4 Flags 1 Mutex

Task/ISR Priority

Period

(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%**

Initializes Keypad, GPS, Clock, RF, and LCD hardware

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

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

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

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)

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

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

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)

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)

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)

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)

SystemTask

*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

Module/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

Module/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

Module/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

Module/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 ROM

8kb RAM

Kernel Choice Tasks

StartTask RFrxISR GPSrxISr SysTask KeyTask ClockTask

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

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