Espressif ESP8266 Technical Reference page 35

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isr,
bit,
master,
isr,
Code description: As SPI store the FLASH chip by the read/write program, HSPI is used for
communication. For ESP8266 processor, there are multiple devices that share the
interruption function, including SPI module, HSPI module, I2S module, the 4's, 7's and 9's
0x3ff00020 in the register.
As SPI module triggers transmission interruption frequently, 5 interruption source enabled
should be closed. The corresponding codes are as follows:
regvalue=READ_PERI_REG(SPI_FLASH_SLAVE(SPI));
regvalue&=~(0x3ff);
WRITE_PERI_REG(SPI_FLASH_SLAVE(SPI),regvalue);
If HSPI is triggered, software that resets the 5 interruption source is needed, in order to
avoid the repeated interruption function. The corresponding codes are as follows:
Espressif
//following 3 lines is to close spi isr enable
regvalue=READ_PERI_REG(SPI_FLASH_SLAVE(SPI));
regvalue&=~(0x3ff);
WRITE_PERI_REG(SPI_FLASH_SLAVE(SPI),regvalue);
//os_printf("SPI ISR is trigged\n"); //debug code
}else if(READ_PERI_REG(0x3ff00020)&BIT7){ //bit7 is for hspi
//following 3 lines is to clear hspi isr signal
regvalue=READ_PERI_REG(SPI_FLASH_SLAVE(HSPI));
regvalue&=~(0x1f);
WRITE_PERI_REG(SPI_FLASH_SLAVE(HSPI),regvalue);
//when master command is write slave 0x04,
//recieved data will be occur in register SPI_FLASH_C0's low 8
//also if master command is read slave 0x06,
//the low 8bit data in register SPI_FLASH_C0 will transmit to
//so prepare the transmit data in SPI_FLASH_C0' low 8bit,
//if a slave transmission needs
recv_data=(uint8)READ_PERI_REG(SPI_FLASH_C0(HSPI));
/*put user code here*/
// os_printf("recv data is %08x\n", recv_data);//debug code
}else if(READ_PERI_REG(0x3ff00020)&BIT9){ //bit9 is for i2s
}
26 86 ! /!
4. SPI Communication User Guide
2016.05