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/***************************************************************************
* Copyright (C) 2010 by Spencer Oliver *
* spen@spen-soft.co.uk *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the *
* Free Software Foundation, Inc., *
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *
***************************************************************************/
.text
.arm
.arch armv5t
.section .init
/*
r0 source address (in)
r1 target address (in)
r2 word count (in)
r3 result (out)
*/
write:
bic r4, r1, #3 /* word address */
mov r3, #0x40 /* write command */
strh r3, [r4, #0]
ldrh r3, [r0], #2 /* read data */
strh r3, [r1], #2 /* write data */
mov r3, #0x70 /* status command */
strh r3, [r4, #0]
busy:
ldrb r3, [r4, #0] /* status */
tst r3, #0x80
beq busy
mov r5, #0x50 /* clear status command */
strh r5, [r4, #0]
mov r5, #0xFF /* read array */
strh r5, [r4, #0]
tst r3, #0x12
bne exit
subs r2, r2, #1 /* decremment word count */
bne write
exit:
bkpt #0
.end
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