diff options
Diffstat (limited to 'hexedit/uart.s')
| -rw-r--r-- | hexedit/uart.s | 53 |
1 files changed, 1 insertions, 52 deletions
diff --git a/hexedit/uart.s b/hexedit/uart.s index 9804e53..b845c8b 100644 --- a/hexedit/uart.s +++ b/hexedit/uart.s @@ -2,60 +2,9 @@ .cpu cortex-m0plus .thumb -.equ RESETS_BASE, 0x4000c000 -.equ RESET_OFST, 0x0 -.equ RESET_DONE_OFST, 0x8 - -.equ IO_BANK0_BASE, 0x40014000 -.equ GPIO0_CTRL_OFST, 0x04 -.equ GPIO1_CTRL_OFST, 0x0c - .equ UART0_BASE, 0x40034000 .equ UARTDR_OFST, 0x00 .equ UARTFR_OFST, 0x18 -.equ UARTIBRD_OFST, 0x24 -.equ UARTFBRD_OFST, 0x28 -.equ UARTLCR_H_OFST, 0x2c -.equ UARTCR_OFST, 0x30 - -.equ ATOMIC_SET, 0x2000 -.equ ATOMIC_CLEAR, 0x3000 - -.type setup_uart, %function -.global setup_uart - -setup_uart: - - // Deassert reset - ldr r1, =(RESETS_BASE + ATOMIC_CLEAR) - movs r0, 0b1 // UART0 - lsls r0, 22 - str r0, [r1, RESET_OFST] - ldr r1, =RESETS_BASE -1: - ldr r2, [r1, RESET_DONE_OFST] - tst r2, r0 - beq 1b - - // Configure and enable - ldr r1, =UART0_BASE - movs r0, 6 - str r0, [r1, UARTIBRD_OFST] - movs r0, 33 - str r0, [r1, UARTFBRD_OFST] - movs r0, 0b111 << 4 // 0b11 = word len 8 bits, 0b1 = FIFO enabled - str r0, [r1, UARTLCR_H_OFST] - ldr r1, =(UART0_BASE + ATOMIC_SET) - movs r0, 0b1 // UART enable - str r0, [r1, UARTCR_OFST] - - // Configure GPIO 0 and 1 as TX and RX - ldr r1, =IO_BANK0_BASE - movs r0, 2 // UART function - str r0, [r1, GPIO0_CTRL_OFST] - str r0, [r1, GPIO1_CTRL_OFST] - - bx lr .type uart_send, %function .global uart_send @@ -104,7 +53,7 @@ send_hex: adds r0, '0 b 2f 1: - adds r0, 'A - 0xA + adds r0, ('A - 0xA) 2: bl uart_send subs r5, 1 |