ESP8266 datasheet(32/117 Pages) ESPRESSIF

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4. SPI Communication User Guide

5. void spi_byte_write_espslave(uint8 spi_no,uint8 data)

Function:

Write a Byte data for slave SPI.

As the slave is set at 7bits command+1bit address+8bits data, data sending requires 16

bits transmission and the ﬁrst byte is 0b0000010+0 refer to 3.3

, i.e. 0x04. The second

byte is data sending. The actual transmitting waveform is illustrated in Figure 4-1.

Figure 4-1. The waveform of spi_byte_write_espslave written into slave ESP8266

6. void spi_byte_read_espslave(uint8 spi_no,uint8 *data)

Function:

Read one byte data from slave SPI and read other SPI slave devices. As the slave device is

set at 7bits command+1bit address+8bits data, data sending requires 16 bits transmission

and the ﬁrst byte is 0b0000011+0 (refer to

Section 4.3.3), i.e. 0x06. The second Byte is

data sending. The actual operating waveform is illustrated in Figure 4-2.

Parameter

Description

uint8 spi_no

The number of SPI module. Only input SPI(0) and

HSPI(1). Any other inputs are invalid.

uint8 data

8 bit data sending.

Parameter

Description

uint8 spi_no

The number of SPI module. Only input SPI(0) and

HSPI(1). Any other inputs are invalid.

uint8 data

8 bit data sending.

! Note:

Yellow line: CS, blue line: CLK, red line: MOSI, green line: MISO.

Espressif

! /!

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2017.05

ESP8266 Datasheet(PDF) 32 Page - ESPRESSIF SYSTEMS (SHANGHAI) CO., LTD.