altos: Add attiny architecture files

These are designed to work with the ATtiny85 processor, but can
presuambly be easily adapted to others in that series

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/src/attiny/ao_eeprom_tiny.c b/src/attiny/ao_eeprom_tiny.c
new file mode 100644
index 00000000..83014183
--- /dev/null
+++ b/src/attiny/ao_eeprom_tiny.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>
+
+static void
+ao_eeprom_wait(void)
+{
+	/* Wait for previous write to complete */
+	while (EECR & (1 << EEPE))
+		;
+}
+
+static uint8_t
+ao_eeprom_read_byte(uint16_t addr)
+{
+	uint8_t	v;
+
+	ao_eeprom_wait();
+	EEAR = addr;
+	cli();
+	EECR |= (1 << EERE);
+	v = EEDR;
+	sei();
+	return v;
+}
+
+static void
+ao_eeprom_write_byte(uint16_t addr, uint8_t v)
+{
+	ao_eeprom_wait();
+	EECR = (0 << EEPM1) | (0 << EEPM0);
+	EEAR = addr;
+	EEDR = v;
+	cli();
+	EECR |= (1 << EEMPE);
+	EECR |= (1 << EEPE);
+	sei();
+}
+
+void
+ao_eeprom_read(uint16_t addr, void *buf, uint16_t len)
+{
+	uint8_t	*b = buf;
+
+	while (len--)
+		*b++ = ao_eeprom_read_byte(addr++);
+}
+
+void
+ao_eeprom_write(uint16_t addr, void *buf, uint16_t len)
+{
+	uint8_t	*b = buf;
+
+	while (len--)
+		ao_eeprom_write_byte(addr++, *b++);
+}