# smbus2
來源：https://smbus2.readthedocs.io/en/latest/?badge=latest

github
https://github.com/kplindegaard/smbus2

update(change log)：https://github.com/kplindegaard/smbus2/blob/master/CHANGELOG.md

持續學習中，如有錯誤歡迎留言賜教

smbus2 is pure Python implementation of of the python-smbus package.

It was designed from the ground up with two goals in mind:

It should be a drop-in replacement of smbus. The syntax shall be the same.
Use the inherent i2c structs and unions to a greater extent than other pure Python implementations like pysmbus does. By doing so, it will be more feature complete and easier to extend.

### wirte:
write_byte(I2C_Slave_address[slave_num], value)
arduino收到是 資料 故總共有 1 byte數

write_i2c_block_data(I2C_Slave_address[slave_num], 0x00 , data)
arduino收到是 起始位址+資料 故總共有 資料長度+1 byte數

write_block_data(I2C_Slave_address[slave_num], 0x08 , data)
arduino收到是 起始位址+資料長度+資料 故總長度有 資料長度+2 byte數

write_byte_data(I2C_Slave_address[slave_num], 0x05, value,)
arduino收到是 起始位址+資料 故總長度有 2 byte數

write_word_data(I2C_Slave_address[slave_num], 0x05, value,)
arduino收到是 起始位址+2byte的整數(0~65535) 故總長度有 3 byte數
P.S. 1word = 2byte

### read:
以write_block_data(I2C_Slave_address[slave_num], 0x05 , data) 寫入 [ 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112]，arduino收到後顯示 [ 5 , 8 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112]

read_byte(I2C_Slave_address[slave_num])
rpi收到 5

read_byte_data(I2C_Slave_address[slave_num], 0x0a)
rpi收到10 arduino資料被改為[ 10 , 8 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112]

read_block_data(I2C_Slave_address[slave_num], 0)
rpi收到[]

read_i2c_block_data(I2C_Slave_address[slave_num], 0 , 16)
rpi收到[ 0 , 8 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 0 , 0 , 0 , 0 , 0 , 0]
用for 迴圈將資料以Wire.write()分多次丟給rpi