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view target-utils/libcommon/serio.S @ 141:f8bb6cd4edd3

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k5a3281.init (for GTA0x): set WS=3 for nCS0 like the official firmware does
author Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
date Tue, 12 Nov 2013 04:53:30 +0000
parents 40f607bb0a2c
children d7591faa1258
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#include "ns16550.h"

@ this module implements the elementary serial I/O operations

	.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
	mvneq	r0, #1
	bxeq	lr
	ldrb	r0, [r2, #NS16550_RBR]
	bx	lr