Questions tagged [mcp23s17]
The mcp23s17 tag has no usage guidance.
11
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Why is the MCP23S17 device getting too hot suddenly and randomly?
Circuit is a Raspberry Pi 4A SPI master node talking with one MCP23S17 device. I'm testing the single-circuit version in a protoboard.
We are using A bank GPIOs for reading, and B bank GPIOs for ...
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MCP23S17 - do I have to use both Chip Select and Hardware Addressing?
I've used MCP23S17 before. 6 of it and I just used Chip Select. Hardware address pins all 0.
https://ww1.microchip.com/downloads/en/DeviceDoc/20001952C.pdf
In datasheet, hardware addressing can be ...
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MCP23017 - control N-channel mosfets
In my current design, I have a few devices connected to 5v and 3.3V rails from an off the shelf ESP32 development board that has an onboard 18650 battery. My problem is if I want to run off battery, ...
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MCP23017 link to an optocoupler Rail input
In my project I have an optocoupler Rail 32 units like the proto below . I want to link it to my MCU with 2 mcp23017 digital Input . Do I need to put a Schmitt Trigger before the mcp23017 to have a ...
2
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MCP23017 open drain interrupts not working as expected
I have multiple MCP23017 ICs with their interrupts all connected in serial. The interrupt pins are configured to be open-drain.
All the A port interrupt pins are connected together and all the B port ...
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MCP23017 INT Pin always high - INT cannot be cleared
trying to enable INT on MCP23017 so that, in case of a state change on any PIN from Port A (e.g from low to high) an interrupt should be triggered on INTA.
Unfortunately the INTA pin remains high as ...
3
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779
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Pressing one key in a button matrix reads all keys in that column
I'm using an MCP23017 IO Expander to make a button matrix (4x4).
...
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Connecting loads to an MCP23S17 GPIO outputs
I would like to connect various MCP23S17 datasheet devices to the Raspberry Pi3 MB SPI port. But first I would like to start making some test with a single connection: only one chip. After this I will ...
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What about MCP23S17 GPIO pins output ports being also used to be read by input pins?
We are connecting Raspberry Pi3B with some MCP23S17 expanders:
MCP23S17.
I have read that they could emulate an open-drain outputs, playing with high Z state of the pin when configured as input. ...
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Does a Mcp23s17 output pin keep the value after being unselected?
I'm designing a SPI based communiations circuit between Raspberry Pi4+B as a master and (n x 8) GPIO expander modules, as slaves. Concretely we have selected an MCP23S17 GPIO expander: Datasheet
By ...
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MCP23S17 IOCON register values do not update correctly
I am currently testing the functionality of a Microchip MCP23S17 SPI 16-bit GPIO port expander for an application with a number of external inputs & outputs. The initial configuration of an ...