Questions tagged [expander]
Questions regarding Port or IO Expanders, be it I2C, SPI, 1-Wire, serial/uart or similar. Shift-Registers are normally NOT considered Expanders, and have their own tag.
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How do I connect non-I2C devices to an I2C bus?
I'm quite new to electronics and just trying to do my first Raspberry Pi based system: one diode, one pressure sensor and LCD 1602 with keypad shield (the one for an Arduino board). The way I'd like ...
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Interfacing a MCP23S17 (SPI) with a FPGA
I am working with a MCP23S17 SPI I/O expander chip in a VHDL project on my Basys 2.
At first glance I thought this was just a simple SPI interface where I put the chip select low and it will give me ...
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Multiplex two I2C ICs into four 7 Segment displays
I currently have two PCF8574AN I2C 8-bit IO expander ICs. Is there a way I could have two seven segments be driven off one IC (So i could run four seven segments displays off the two ICs that I have). ...
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PIC, SPI problem with SD card and other devices
I'm using a PIC24H as a master connected with a microSD card, ENC28J60 and a MCP28S08 port expander. I'm using the FatFs library for a microSD card and the Microchip TCP/IP stack for ENC28J60.
All ...
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Battery powered sensor node power down circuit
I am using the BQ24079T to control power for a wireless, battery powered sensor node. The MCU will operate in one of two modes: periodic sample mode where it takes sensor readings and then sleeps, or ...
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Simplifying a relay network
I'm currently trying to design a relay network for a piece of laboratory equipment (PPMS). I would like to describe what the setup is, what I am doing now, what I hope to do, and how I hope to do it. ...
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Good solution for more interrupts on an arduino?
I'm building a circuit with an Arduino Mega and simple IC chips (e.g. 7432) but I have many lines to monitor for interrupt conditions and not enough pins on the Atmel so I'm looking for a way to ...
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Problem writing to MCP23017 I/O Expander registers (i2c)
I am creating a basic cable tester device and using I2C to interface with two MCP23017 I/O expander chips.
In my code each MCP23017 slave has its own address and I can communicate with both of them ...
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GPIO Expander with isolation
Is there any GPIO expander with galvanic isolation? I browsed a lot and couldnt find any GPIO expander with isolation.Thanks in advacne
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Controlling more relays than the no. of free IO pins a uC has - Low-cost options
While I understand that moving up to a high pin-count uC might be the simplest option, I am looking for Low-cost options to do the same with low pin-count uC.
Would like to control a maximum of 8 ...
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