diff options
| author | Bdale Garbee <bdale@gag.com> | 2013-12-19 01:38:40 -0700 |
|---|---|---|
| committer | Bdale Garbee <bdale@gag.com> | 2013-12-19 01:38:40 -0700 |
| commit | 575bbaf976c5840fd0e308549c45a466fdec1352 (patch) | |
| tree | 11bfb498348bf7687bffc24699c4b1a998988ee4 /src/attiny/ao_async.c | |
| parent | b825116df173b77e2cab217a7b76112c742f9279 (diff) | |
| parent | bc3610d8cecbfed40c62d4dcb93fc9a4d2a7c9e3 (diff) | |
Merge branch 'branch-1.3' into debian
Conflicts:
ChangeLog
altoslib/AltosRecordMM.java
altosui/Makefile.am
altosui/altos-windows.nsi.in
configure.ac
debian/changelog
debian/control
doc/Makefile
doc/altusmetrum.xsl
doc/release-notes-1.2.1.xsl
doc/release-notes-1.2.xsl
Diffstat (limited to 'src/attiny/ao_async.c')
| -rw-r--r-- | src/attiny/ao_async.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/src/attiny/ao_async.c b/src/attiny/ao_async.c new file mode 100644 index 00000000..3556f54c --- /dev/null +++ b/src/attiny/ao_async.c @@ -0,0 +1,71 @@ +/* + * Copyright © 2012 Keith Packard <keithp@keithp.com> + * + * 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; version 2 of the License. + * + * 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., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ + +#include <ao.h> +#include <ao_async.h> + +#define AO_ASYNC_BAUD 38400l +#define AO_ASYNC_DELAY (uint8_t) (1000000l / AO_ASYNC_BAUD) + +#define LED_PORT PORTB + +void +ao_async_start(void) +{ + LED_PORT |= (1 << AO_LED_SERIAL); +} + +void +ao_async_stop(void) +{ + LED_PORT &= ~(1 << AO_LED_SERIAL); +} + +void +ao_async_byte(uint8_t byte) +{ + uint8_t b; + uint16_t w; + + /* start data stop */ + w = (0x000 << 0) | (byte << 1) | (0x001 << 9); + + ao_arch_block_interrupts(); + for (b = 0; b < 10; b++) { + uint8_t v = LED_PORT & ~(1 << AO_LED_SERIAL); + v |= (w & 1) << AO_LED_SERIAL; + LED_PORT = v; + w >>= 1; + + /* Carefully timed to hit around 9600 baud */ + asm volatile ("nop"); + asm volatile ("nop"); + + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + } + ao_arch_release_interrupts(); +} |