I want to use esp8266 as spi slave connected to a LPC4376 μC (spi master).
I cannot unserstand the first paragraph of the epressif technical reference document,
"This protocol uses the ESP8266 slave mode to communicate with other processor's SPI master. Signal line No.5 is used to implement this protocol. Apart from signal line No.4 needed for standard SPI, signal line No.1 is also needed to inform the master of the update of the slave status register."
What is line no 5? what are the other lines that are mentioned?
Do i need a gpio line besides clk, cs, miso, mosi, in order to esp generate interrupts to the master mcu?
The spi slave example from unofficial examples don't work.
viewtopic.php?f=9&t=820
Any suggestion or sample code for spi slave?
Plz i really need some help