.include "memorymap/uart.s"

.align 2
.arm
.global io_uart_dataready
#Check if a UART has data available.
#Parameters: r0=base address of the UART to check
#Sets r0 to nonzero if data is ready.
io_uart_dataready:
        ldr r1, [r0, UART.LSR]
        ldr r2, =0x7FFFFFFFFF
        and r3, r1, r2
        str r3, [r0, UART.LSR]
        bx lr