Update: Currently no valid layout pending a change. Development HAT for nRF52840 using Fanstel's BT840/BT840E/BT840F/BT840X and SC16IS752 to provide serial uarts for HCI and debug (or whatever firmware is loaded). Also features SWD programming from OpenOCD and a ID EEPROM to aid the development of a Coded PHY (aka BLE long range) HAT for Raspberry PI compatible boards using the Zephyr HCI Uart code. On the Pi the SC16IS752 needs two recent patches to the kernel/firmware to work properly, a device tree patch that allows the X1 frequency to be passed as a argument to the overlay (so we can use the 11.0592Mhz chrystal from the basic selection). And a patch to fix the hardware flow control that is neccecary for the HCI UART interface with Zephyr firmware. (Saleae Logic Pro 8 was instrumental in tracking down the issue with CTS in the driver) - https://github.com/raspberrypi/linux/commit/804d8f832ecde209afa6201c2e27aeb106e22396 * - https://github.com/raspberrypi/linux/commit/5377449ffb6ffe9ebfee939d52b2611130fbb836 *) if using ID EEPROM you can skip the device tree patch and use the correct eeprom bin file that has the overlay file in it and it will be loaded automagically. see attachments for files and https://github.com/raspberrypi/hats/tree/master/eepromutils for the tools to write the eeprom. The 0R resistor `WP` needs to be installed or shorted across to allow writing to EEPROM. Verified the M24C64-RMN6TP from the basic selection is equivalent the OnSemi CAT24C32 that the Raspberry Pi HAT spec reccoments, its also cheaper - yay! bom and cpl are in the attachments. no need to fit 32khz crystal if planning to use bt840x (or it can also run with internal rc osccilator if needed, but bt840x has the xtal). firmware is work in progress but the basic hci uart + debug uart works with the attached zephyr.hex file or can be built from zephyr (custom board definition on github soon(tm)) ``` #!!modified!! nrf52840dk_nrf52840 board #build host west build -p always -b nrf52840dk_nrf52840 zephyr/samples/bluetooth/hci_uart && \ scp build/zephyr/zephyr.hex pi@raspberrypi:~/zephyr.hex && \ ssh pi@raspberrypi "nohup sudo openocd -f ~/openocd/openocd.cfg &> /tmp/openocd.out