FreeCalypso > hg > freecalypso-tools
view target-utils/libbase/serio.S @ 416:30f6d1c32c6f
doc/Flash-boot-defect article removed (no longer relevant)
This article is no longer relevant because the issue in question
only affected one (1) defective FCDEV3B board which was not
and never will be sold.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Fri, 26 Oct 2018 07:11:08 +0000 |
parents | da6df2c626cf |
children |
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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, #0x11] @ Calypso UART non-std register SSR tst r3, #0x01 @ Tx FIFO full flag bne 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