FreeCalypso > hg > freecalypso-tools
view target-utils/libbase/serio.S @ 33:cefdc6623322
fc-e1gen utility written, compiles
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Tue, 25 Oct 2016 06:49:27 +0000 |
parents | e7502631a0f9 |
children | da6df2c626cf |
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#include "ns16550.h" @ this module implements the elementary serial I/O operations .comm uart_base,4,4 .text .code 32 .global serial_out serial_out: ldr r1, =uart_base ldr r2, [r1] 1: ldrb r3, [r2, #NS16550_LSR] tst r3, #NS16550_LSR_THRE beq 1b strb r0, [r2, #NS16550_THR] bx lr .global serial_in_poll serial_in_poll: ldr r1, =uart_base ldr r2, [r1] ldrb r3, [r2, #NS16550_LSR] tst r3, #NS16550_LSR_DR ldrneb r0, [r2, #NS16550_RBR] mvneq r0, #0 bx lr .global serial_flush serial_flush: ldr r1, =uart_base ldr r2, [r1] 1: ldrb r3, [r2, #NS16550_LSR] tst r3, #NS16550_LSR_TEMP beq 1b bx lr