SPI – Serial Peripheral Interface Bus Protocol

2025-03-25

This class provides bus protocol of serial peripheral interface (SPI) .

Constructor

`machine.SPI`

class machine.SPI(spi, mode, clk, [group])

Parameter:

port - Integer type. Channel selection: [0,1].
mode - SPI working mode.
Clock polarity CPOL: The pin level of clock signal SCLK when SPI is idle (0: low level; 1: high level)
0 ： CPOL=0, CPHA=0
1 ： CPOL=0, CPHA=1
2 ： CPOL=1, CPHA=0
3 ： CPOL=1, CPHA=1
clk - Clock frequency.
0 ： 812.5kHz
1 ： 1.625MHz
2 ： 3.25MHz
3 ： 6.5MHz
4 ： 13MHz
5 ： 26MHz
6 ： 52MHz

The 52MHz clock frequency has high requirements for hardware.

class machine.SPI(spi, mode, clk, [group])

Parameter:

port - Integer type. Channel selection: [0,1].
mode - SPI working mode.
Clock polarity CPOL: The pin level of clock signal SCLK when SPI is idle (0: low level; 1: high level)
0 ： CPOL=0, CPHA=0
1 ： CPOL=0, CPHA=1
2 ： CPOL=1, CPHA=0
3 ： CPOL=1, CPHA=1
clk - Clock frequency.
0 ： 812.5kHz
1 ： 1.625MHz
2 ： 3.25MHz
3 ： 6.5MHz
4 ： 13MHz
[group] - Select to use SPI on different pins, with a default value of 0.
1 ： This group of pins does not support mounting nor flash.

class machine.SPI(spi, mode, clk, [group])

Parameter:

port - Integer type. Channel selection: [0,1].
mode - SPI working mode.
Clock polarity CPOL: The pin level of clock signal SCLK when SPI is idle (0: low level; 1: high level)
0 ： CPOL=0, CPHA=0
1 ： CPOL=0, CPHA=1
2 ： CPOL=1, CPHA=0
3 ： CPOL=1, CPHA=1
clk - Clock frequency.
0 ： 812.5kHz
1 ： 1.625MHz
2 ： 3.25MHz
3 ： 6.5MHz
4 ： 13MHz

class machine.SPI(spi, mode, clk, [group])

Parameter:

port - Integer type. Channel selection: [0,1].
mode - SPI working mode.
Clock polarity CPOL: The pin level of clock signal SCLK when SPI is idle (0: low level; 1: high level)
0 ： CPOL=0, CPHA=0
1 ： CPOL=0, CPHA=1
2 ： CPOL=1, CPHA=0
3 ： CPOL=1, CPHA=1
clk - Clock frequency.
0 ： 781.25KHz
1 ： 1.5625MHz
2 ： 3.125MHz
3 ： 5MHz
4 ： 6.25MHz
5 ： 10MHz
6 ： 12.5MHz
7 ： 20MHz
8 ： 25MHz
9 ： 33.33MHz

class machine.SPI(spi, mode, clk, [group])

Parameter:

port - Integer type. Channel selection: [0,1].
mode - SPI working mode.
Clock polarity CPOL: The pin level of clock signal SCLK when SPI is idle (0: low level; 1: high level)
0 ： CPOL=0, CPHA=0
3 ： CPOL=1, CPHA=1
clk - Clock frequency.
0 ： 781.25KHz
X ： XMHz (X in [1,39])

class machine.SPI(spi, mode, clk, [group])

Parameter:

port - Integer type. Channel selection: [0,1].
mode - SPI working mode.
0 ： 97.656kHz
1 ： 100kHz
2 ： 812.5kHz
3 ： 1.3MHz
4 ： 1.625MHz
5 ： 2MHz
6 ： 3.25MHz
7 ： 4.333MHz
8 ： 6.6MHz
9 ： 11.93MHz
10 ： 13MHz
11 ： 13.92MHz
12 ： 16.7MHz
13 ： 20.875MHz
14 ： 27.83MHz

class machine.SPI(spi, mode, clk, [group])

Parameter:

port - Integer type. Channel selection: [0,1].
mode - SPI working mode.
Clock polarity CPOL: The pin level of clock signal SCLK when SPI is idle (0: low level; 1: high level)
0 ： CPOL=0, CPHA=0
1 ： CPOL=0, CPHA=1
2 ： CPOL=1, CPHA=0
3 ： CPOL=1, CPHA=1
clk - Clock frequency.
0 ： 500kHz
1 ： 1MHz
2 ： 5MHz
3 ： 10MHz
4 ： 20MHz

Example:

>>> from machine import SPI
>>> # Creates a SPI object
>>> spi_obj = SPI(1, 0, 1)

SPI Pin Correspondences:

SPI	CS	CLK	MOSI	MISO
spi0	pin4	pin1	pin3	pin2
spi1	pin58	pin61	pin59	pin60

SPI	CS	CLK	MOSI	MISO
spi0	pin134	pin133	pin132	pin131
spi1	pin26	pin27	pin24	pin25

SPI	CS	CLK	MOSI	MISO
spi0	pin31	pin30	pin32	pin33
spi1	pin52	pin53	pin50	pin51

SPI	CS	CLK	MOSI	MISO
spi0	pin6	pin5	pin4	pin3

SPI	CS	CLK	MOSI	MISO
spi0	pin25	pin26	pin27	pin28
spi1	pin41	pin40	pin64	pin65
spi2	pin19	pin18	pin23	pin22

SPI	CS	CLK	MOSI	MISO
spi0 group0	pin25	pin26	pin27	pin28
spi0 group1	pin4	pin1	pin3	pin2
spi1 group0	pin4	pin1	pin3	pin2
spi1 group1	pin65	pin67	pin66	pin63
spi2	pin49	pin54	pin53	pin52

SPI	CS	CLK	MOSI	MISO
spi0	pin25	pin26	pin64	pin88
spi1	pin5	pin4	pin6	pin7

SPI	CS	CLK	MOSI	MISO
spi0 group0	pin31	pin30	pin32	pin33
spi0 group1	pin52	pin53	pin50	pin51
spi1 group0	pin52	pin53	pin50	pin51
spi1 group1	pin69	pin68	pin85	pin84
spi2	pin76	pin77	pin78	pin16

SPI	CS	CLK	MOSI	MISO
spi0 group0	pin31	pin30	pin32	pin33
spi0 group1	pin52	pin53	pin50	pin51
spi1 group0	pin52	pin53	pin50	pin51
spi1 group1(EG810M_EU unsupported)	pin69	pin68	pin85	pin84
spi2	pin76	pin77	pin78	pin16

SPI	CS	CLK	MOSI	MISO
spi0	pin25	pin26	pin27	pin28
spi1	pin5	pin4	pin6	pin7

SPI	CS	CLK	MOSI	MISO
spi0	pin37	pin40	pin38	pin39
spi1	pin26	pin27	pin25	pin24

SPI	CS	CLK	MOSI	MISO
spi0	pin37	pin40	pin38	pin39
spi1	pin26	pin27	pin25	pin24

SPI	CS	CLK	MOSI	MISO
spi0(EC600ECN_LE&LQ unsupported)	pin65	pin67	pin66	pin64
spi1	pin69	pin71	pin70	pin72

SPI	CS	CLK	MOSI	MISO
spi0	pin28	pin39	pin29	pin38
spi1(EC800ECN_LE&LQ&CG unsupported)	pin52	pin53	pin50	pin51

SPI	CS	CLK	MOSI	MISO
spi0	pin4	pin1	pin3	pin2
spi1(EC800ECN_LE&LQ&CG unsupported)	pin53	pin52	pin54	pin51

SPI	CS	CLK	MOSI	MISO
spi1	pin79	pin101	pin100	pin108

SPI	CS	CLK	MOSI	MISO
spi0(EG912UGLAA unsupported)	pin25	pin26	pin64	pin88
spi1	pin5	pin4	pin6	pin7

SPI	CS	CLK	MOSI	MISO
spi1	pin4	pin1	pin3	pin2
spi2	pin58	pin61	pin59	pin60

SPI	CS	CLK	MOSI	MISO
spi0	pin31	pin30	pin32	pin33
spi1	pin52	pin53	pin50	pin51
spi2	pin74	pin75	pin76	pin77

SPI	CS	CLK	MOSI	MISO
spi0	pin31	pin30	pin32	pin33
spi1	pin52	pin53	pin50	pin51
spi2	pin74	pin75	pin76	pin77

SPI	CS	CLK	MOSI	MISO
spi0	pin21	pin22	pin29	pin23

SPI	CS	CLK	MOSI	MISO
spi0	pin29	pin30	pin37	pin31

SPI	CS	CLK	MOSI	MISO
spi0	pin41	pin42	pin43	pin44

SPI	CS	CLK	MOSI	MISO
spi0	pin41	pin42	pin43	pin44

SPI	CS	CLK	MOSI	MISO
spi0	pin5	pin4	pin6	pin7

SPI	CS	CLK	MOSI	MISO
spi0	pin49	pin29	pin101	pin28
spi1	pin52	pin53	pin50	pin51

Methods

`SPI.read`

SPI.read(recv_data, datalen)

This method reads data.

Parameter:

recv_data - Bytearray type. An array used to receive data.
datalen - Integer type. Length of the data to be read.

Return Value:

0 - Successful execution

-1 - Failed execution

`SPI.write`

SPI.write(data, datalen)

This method writes data.

Parameter:

data - Bytearray type. Data to be written.
datalen - Integer type. Length of data to be written.

Return Value:

0 - Successful execution

-1 - Failed execution

`SPI.write_read`

SPI.write_read(r_data, data, datalen)

This method writes and reads data.

Parameter:

r_data - Bytearray type. An array used to receive data.
data - Bytearray type. Data to be sent.
datalen - Integer type. Length of data to be read.

Return Value:

0 - Successful execution

-1 - Failed execution

`SPI.close`

SPI.close()

This method close SPI.

Return Value:

0 - Successful execution

-1 - Failed execution

Example:

Please use this function with the peripherals.

import log
from machine import SPI
import utime



spi_obj = SPI(0, 0, 1)

# Sets the log output level 
log.basicConfig(level=log.INFO)
spi_log = log.getLogger("SPI")


if __name__ == '__main__':
    r_data = bytearray(5)  # Creates a buff for receiving data
    data = b"world"  # Tests data

    ret = spi_obj.write_read(r_data, data, 5)  # Writes data and receives data to r_data
    spi_log.info(r_data)

I2C_simulation - Software Implementation of I2C Protocol

SoftSPI - Software Implementation of SPI Protocol

型号选择：

QuecPython

SPI – Serial Peripheral Interface Bus Protocol

Constructor

machine.SPI

Methods

SPI.read

SPI.write

SPI.write_read

SPI.close

`machine.SPI`

`SPI.read`

`SPI.write`

`SPI.write_read`

`SPI.close`