12-13-2021, 10:38 AM
(This post was last modified: 12-13-2021, 04:14 PM by CounterPillow.
Edit Reason: ROCK64 lacks the pull-ups, so not supported without modification
)
Hello,
I'm currently working on a GPIO expander HAT that fits the ROCKPro64 and Quartz64. Here's a 3D render of the current prototype board:
![[Image: 3d%20render%20rev%201.png]](https://overviewer.org/~pillow/up/cc6241625e/3d%20render%20rev%201.png)
It uses the I²C pins to provide an additional 16 GPIOs, and can be stacked up to 8 times for a total of 128 GPIOs. Each board has an interrupt pin for bank A and B (8 pins each), which can be configured to fire when the input on a pin changes.
The terminal block is a screwless terminal, and can be accessed even when multiple boards are stacked on top of each other.
The boards are based on the MCP23017 chip from Microchip, which can run at up to 1.7 MHz. Each I/O pin can provide 25 mA.
It'll be a while before I have some prototypes assembled as the IC is on backorder for the next few weeks, but I wanted to gauge whether there's any interest in doing an actual production run of these boards using surface mount components and improvements discovered while using the prototype run.
So if you're interested, let me know in the thread, and name what price you'd be willing to pay per board. I'm currently aiming for maybe $15/board as a target.
I'm currently working on a GPIO expander HAT that fits the ROCKPro64 and Quartz64. Here's a 3D render of the current prototype board:
It uses the I²C pins to provide an additional 16 GPIOs, and can be stacked up to 8 times for a total of 128 GPIOs. Each board has an interrupt pin for bank A and B (8 pins each), which can be configured to fire when the input on a pin changes.
The terminal block is a screwless terminal, and can be accessed even when multiple boards are stacked on top of each other.
The boards are based on the MCP23017 chip from Microchip, which can run at up to 1.7 MHz. Each I/O pin can provide 25 mA.
It'll be a while before I have some prototypes assembled as the IC is on backorder for the next few weeks, but I wanted to gauge whether there's any interest in doing an actual production run of these boards using surface mount components and improvements discovered while using the prototype run.
So if you're interested, let me know in the thread, and name what price you'd be willing to pay per board. I'm currently aiming for maybe $15/board as a target.
Occasional Linux Kernel Contributor, Avid Wiki Updater, Ask Me About Quartz64
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