altos: Place rom config variables in fixed location

The device serial number and radio calibration values are stored in
flash, mostly so that TeleDongle gets them saved.

Placing them in well-known locations (starting at 0xa0) makes it
possible to find the previous configuration and to re-write it
easily, without requiring the .map file.

altosui doesn't have the .map file parsing code, so it relies upon
this new technique. As a benefit, it reads the old values from the
device before reprogramming it.

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

1 files changed, 32 insertions, 0 deletions

diff --git a/src/ao_romconfig.c b/src/ao_romconfig.c
new file mode 100644
index 00000000..f3fe61b1
--- /dev/null
+++ b/src/ao_romconfig.c
@@ -0,0 +1,32 @@
+/*
+ * Copyright © 2010 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"
+
+__code __at (0x00a0) uint16_t ao_romconfig_version = AO_ROMCONFIG_VERSION;
+__code __at (0x00a2) uint16_t ao_romconfig_check = ~AO_ROMCONFIG_VERSION;
+__code __at (0x00a4) uint16_t ao_serial_number = 0;
+/*
+ * For 434.550MHz, the frequency value is:
+ *
+ * 434.550e6 / (24e6 / 2**16) = 1186611.2
+ *
+ * This value is stored in a const variable so that
+ * ao-load can change it during programming for
+ * devices that have no eeprom for config data.
+ */
+__code __at (0x00a6) uint32_t ao_radio_cal = 1186611;