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Software Design. Web Server Base Station for Power Meter By David Hay. System Overview. MCU: MCF52233 (ColdFire Microprocessor) Bus Frequency: 60 MHz Internal Bus Memory Requirements: (Maximums) 8k EEPROM 256k Flash 32k RAM Kernel: ColdFire TCP/IP Lite. Kernel Selection.
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Software Design Web Server Base Station for Power Meter By David Hay
System Overview • MCU: MCF52233 (ColdFire Microprocessor) • Bus Frequency: 60 MHz Internal Bus • Memory Requirements: (Maximums) • 8k EEPROM • 256k Flash • 32k RAM • Kernel: • ColdFire TCP/IP Lite
Kernel Selection • ColdFire TCP/IP Lite • Created for the ColdFire board. • Round-Robin Tasking System. • Upgradeable to a Preemptive RTOS through software. • Includes a TCP/IP Stack for Web Communication. • It’s Free. • It’s new and cool!!!
Task Set-up Priority 1 2 3 4 5 Tasks Start-Up Task. Power Node Handling Task. ColdFire TCP/IP Lite Task. • Preexisting code. Calculations Task. EEPROM Communication Task.
Start-Up Task • Highest Priority. • Initializes the System for Operation. • Period: Runs Once. • Execution Time: N/A • CPU Load: N/A
Power Node Handling Task • Second Highest Priority. • Handles Communication with Power Nodes. • Period: 500 ms • Execution Time: 5 µs/node • CPU Load: .001% per node • 100 Nodes Gives CPU load of .1%
Calculations Task • Third highest Priority. • Averages the Stored Power Values for Previous Weeks to Save on Memory. • Period: 1 Week • Execution Time: 5 µs • CPU Load: 8.3x10(-10)%
EEPROM Communication Task • Fourth Highest Priority. • Handles Saving Received and Recalculated Values to the EEPROM. • Period: 500 ms (Maximum) • Execution Time: 30 ms • CPU Load: 6%
ColdFire TCP/IP Lite Task • Lowest Priority. • Handles The Web Server Communications. • Period: Sporadic • Execution Time: 10 ms (Worst Case) • CPU Load: 1% at 1 Second
CPU Load • Total CPU Load: .001 + 8.3x10(-10) + 6 + 1 = 7.001%