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ARM Team can answer my question on LPC ASM problom???

Jon Bright over 5 years ago

For LPC2148 SoC, a software system call, number 0x55 need to be implemented in assembly language. This system call is used to measure the CPU temperature and raise an alarm if the CPU is overheated. Assume ARM mode of operation. Temperature readings are measured using ADC0 of LPC2148 and the ADC reading is available in raw 10 bit format in arm register R3, you need not to write the code for ADC initialization or control. Threshold value of temperature to activate the alarm is equal to half of the full scale ADC value (1024). Also assume that all the GPIO settings are already done and you just need to write appropriate bits in IOSET register to raise the alarm. Buzzer is connected to P0.10. IO0SET address is 0xE0028004.

What will be the address location (in hexadecimal) where the PC should jump to when system call is made?
What should be the instruction at that address (answer from A) location in order to properly handle the system call?
Write the assembly code for system call handler.

Please help me to get the answers of 3 questions.

Regards,

Jon Bright