Uploaded February 2024 | Updated September 2026, 1 week ago
I wanted to interface a different SPI device, this let’s us test connecting multiple devices at once but I also wanted to try out a different spi mode. In the future I want to interface to a complex mode 0 device so I went looking for a basic mode 0 device to experiment on. I found the MCP23S08 which is an 8 line IO expander. Since the GPIO lines are not being used for SPI this gives us some general purpose IO back!
0:00 Introduction
0:54 Checking the Datasheet
3:23 Current Circuit
4:12 Adding the new device
7:37 Coding Write
18:08 Coding Read
24:40 Outro
I wanted to interface a different SPI device, this let’s us test connecting multiple devices at once but I also wanted to try out a different spi mode. In the future I want to interface to a complex mode 0 device so I went looking for a basic mode 0 device to experiment on. I found the MCP23S08 which is an 8 line IO expander. Since the GPIO lines are not being used for SPI this gives us some general purpose IO back!
0:00 Introduction
0:54 Checking the Datasheet
3:23 Current Circuit
4:12 Adding the new device
7:37 Coding Write
18:08 Coding Read
24:40 Outro
