From: Keith Packard <keithp@keithp.com>
Date: Mon, 6 May 2013 23:08:52 +0000 (-0700)
Subject: altos: Set APRS deviation to 3kHz
X-Git-Tag: 1.2.1~61
X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=3876b5bfad383119339aea51e2cf301012a1f991

altos: Set APRS deviation to 3kHz

I finally found a bunch of references to APRS on the net and they all
appear to assume a 3kHz deviation. Let's see if this works better with
Yaesu radios.

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

diff --git a/src/drivers/ao_cc1120.c b/src/drivers/ao_cc1120.c
index 3bef6c90..772014ee 100644
--- a/src/drivers/ao_cc1120.c
+++ b/src/drivers/ao_cc1120.c
@@ -392,16 +392,15 @@ static const uint16_t rdf_setup[] = {
 };
 
 /*
- * APRS deviation is 5kHz
+ * APRS deviation is 3kHz
  *
  *	fdev = fosc >> 24 * (256 + dev_m) << dev_e
  *
- *     	32e6Hz / (2 ** 24) * (256 + 71) * (2 ** 3) = 4989
+ *     	32e6Hz / (2 ** 24) * (256 + 137) * (2 ** 2) = 2998Hz
  */
 
-#define APRS_DEV_E	3
-#define APRS_DEV_M	71
-#define APRS_PACKET_LEN	50
+#define APRS_DEV_E	2
+#define APRS_DEV_M	137
 
 /*
  * For our APRS beacon, set the symbol rate to 9.6kBaud (8x oversampling for 1200 baud data rate)
diff --git a/src/drivers/ao_cc115l.c b/src/drivers/ao_cc115l.c
index 30c56442..05e6a762 100644
--- a/src/drivers/ao_cc115l.c
+++ b/src/drivers/ao_cc115l.c
@@ -328,11 +328,13 @@ static const uint16_t rdf_setup[] = {
 };
 
 /*
- * APRS deviation is the same as RDF
+ * APRS deviation is 3kHz
+ *
+ * 26e6 / (2 ** 17) * (8 + 7) * (2 ** 0) = 2975
  */
 
-#define APRS_DEV_E	RDF_DEV_E
-#define APRS_DEV_M	RDF_DEV_M
+#define APRS_DEV_E	0
+#define APRS_DEV_M	7
 
 /*
  * For our APRS beacon, set the symbol rate to 9.6kBaud (8x oversampling for 1200 baud data rate)