Lup Yuen Lee 李立源 @lupyuen@social.cleverlibre.org

Tracking all 23 GPIOs used by #PineDio Stack #BL604 can get challenging ... We might reuse GPIOs by mistake! 😱 Our #NuttX GPIO Expander shall validate the GPIOs at startup

https://github.com/lupyuen/bl602_expander#check-reused-gpios

As noted (eloquently) by Robert Lipe, attaching a #BL602 GPIO Interrupt Handler is hard (because our stars are misaligned) ... Let's fix this with our GPIO Expander for Apache #NuttX RTOS

https://github.com/lupyuen/bl602_expander#gpio-interrupts

Handling GPIO Interrupts gets tricky on #PineDio Stack #BL604 ... All GPIO Interrupts are multiplexed into a single IRQ! Our #NuttX GPIO Expander can help

https://github.com/lupyuen/bl602_expander#gpio-interrupts

Apache #NuttX RTOS lets us create I/O Expander Drivers that will handle many GPIOs (Input / Output / Interrupt) ... Perfect for #PineDio Stack #BL604!

https://github.com/lupyuen/bl602_expander#gpio-expander

All 23 GPIOs are fully wired up on #PineDio Stack #BL604! 😲 Let's simplify #NuttX and rename the GPIOs as "/dev/gpio0" to "/dev/gpio22" ... Easier for devs to create NuttX Drivers 👍

https://github.com/lupyuen/bl602_expander#bl602-evb-limitations

What happens when we try to support 23 GPIOs on #PineDio Stack #BL604? Yep the GPIO Names will look really messy on #NuttX RTOS 🤔

https://github.com/lupyuen/bl602_expander#bl602-evb-limitations

#BL602 EVB on #NuttX supports one GPIO Input, one GPIO Output and one GPIO Interrupt ... And names them sequentially: "/dev/gpio0", "/dev/gpio1", "/dev/gpio2" ... Which gets super confusing because "/dev/gpio0" doesn't map to BL602 GPIO Pin 0 🤔

https://github.com/lupyuen/bl602_expander#bl602-evb-limitations

#PineDio Stack #BL604 has an interesting problem on Apache #NuttX RTOS ... Too many GPIOs! Let's make it work 👍

https://github.com/lupyuen/bl602_expander

Apache #NuttX RTOS on #PineDio Stack #BL604 ... Now upgraded to 10.3.0 RC0 👍

https://github.com/lupyuen/incubator-nuttx/tree/pinedio

#BL602 GPIO Expander for Apache #NuttX RTOS ... Coming up next!

https://lupyuen.github.io/articles/touch?23#appendix-gpio-interrupt

Wonder why we must enable I2C Logging ... Or #PineDio Stack's Touch Panel Driver will fail 🤔

https://lupyuen.github.io/articles/touch?22#i2c-logging

I2C Quirks on #BL602 #NuttX ... And our workarounds

https://lupyuen.github.io/articles/touch?21#i2c-quirks

#BL602 Bluetooth LE coming to #NuttX RTOS 🎉

https://github.com/apache/incubator-nuttx/blob/master/boards/risc-v/bl602/bl602evb/src/bl602_bringup.c#L96-L361

#PineDio Stack's display is rotated sideways ... But we can fix this!

https://lupyuen.github.io/articles/touch?20#screen-is-sideways

Patching the Touch Coordinates for #PineDio Stack's Touch Panel

https://lupyuen.github.io/articles/touch?19#touch-up-event

#BL702 doesn't support #RISCV Atomic Operations 🤔

https://bbs.bouffalolab.com/d/133-atomic-memory-operations

How #PineDio Stack's Touch Panel handles a Touch Down Event in #NuttX RTOS

https://lupyuen.github.io/articles/touch?18#touch-down-event

Our #NuttX App reads the data from #PineDio Stack's Touch Panel

https://lupyuen.github.io/articles/touch?17#read-touch-data-1

Here's how we test our Touch Panel Driver for #PineDio Stack #BL604 on Apache #NuttX RTOS

https://lupyuen.github.io/articles/touch?16#run-the-driver

We prevent unnecessary I2C Reads in #PineDio Stack's Touch Panel Driver ... By checking whether the screen has been touched

https://lupyuen.github.io/articles/touch?15#is-data-ready