Cortex-M: Does the event register only get set when an IRQ changes from not pending to pending?

I recently had a race-condition in an application on a Cortex-M4 microcontroller, because I used a wrong order of __SEV() and __WFE() instructions to put my chip to sleep. While debugging this issue,...
Cortex-M: Does the event register only get set when an IRQ changes from not pending to pending?

I recently had a race-condition in an application on a Cortex-M4 microcontroller, because I used a wrong order of __SEV() and __WFE() instructions to put my chip to sleep. While debugging this issue,...
Data in not getting loaded for SPDR register

void main() { SPCR =0xD8; //Enabling SPI int,setting clock EA=1; ES0=1; SPDR=0xFF; //SPI data register while(1); } unsigned char bdata test; sbit SPIF=test^7; void sr_intr() interrupt 4 { test...
Data in not getting loaded for SPDR register

void main() { SPCR =0xD8; //Enabling SPI int,setting clock EA=1; ES0=1; SPDR=0xFF; //SPI data register while(1); } unsigned char bdata test; sbit SPIF=test^7; void sr_intr() interrupt 4 { test...
What will be the reason for MDR register not getting updated??

I'm trying I2C while debugging i found that the I2CMDR register is not updating I'm uploading screenshots below.