(nrf52832 branch) - cannot use two UARTEs #40
Description
On the nRF52840 there are two UARTEs but the nrf52840_peripherals.h file says there are two UARTEs and a single UART. This isn't entirely correct -- the UART is at address 0x40002000, and UARTE0 is at the same address (UARTE1 is at 0x40028000).
Anyway -- since nrf52840_peripherals.h says there is a UART and two UARTEs, the macros at the top of nrf_drv_uart.h will define both NRF_DRV_UART_WITH_UARTE and NRF_DRV_UART_WITH_UART, which causes the build to fail because there's no way to say "two UARTEs and one UART" so it tries to instantiate two UARTs.
How to recreate:
Set up a project where you want to use two UARTEs. I believe the correct app_config.h stanzas are as follows:
#define UART_ENABLED 1
#define UART0_ENABLED 1
#define UART1_ENABLED 1
#define UART_EASY_DMA_SUPPORT 1
In the SDK, apply_old_config.h will take these defines and define NRFX_UARTE_ENABLED, NRFX_UARTE0_ENABLED and NRFX_UARTE1_ENABLED. nrf_drv_uart.h will set up for two UARTEs since UARTE_PRESENT is defined in nrf52840_peripherals.hand also becauseapply_old_config.hcreatedNRFX_UARTE_ENABLED`
This is all perfect until you realize that nrf_drv_uart.h also defines NRF_DRV_UART_WITH_UART since the peripherals.h file says there is a UART as well as two UARTEs.
I believe this is an error, as the nRF52840 has a total of two UART devices with DMA, not three (two with DMA and one without). I think the correct fix is to modify nrf52840_peripherals.h but before I create a PR I wanted to run this by you.