just some more cleanups..

src/linuxaldl.c

@@ -114,9 +114,9 @@ int main(int argc, const char* argv[]){
 	}
 	poptFreeContext(popt_aldl); // free the popt context
 
-	// ========================================================================
-	// 							CONNECT / VERIFY ALDL INTERFACE 
-	// ========================================================================
+	// =======================================================
+	// 	CONNECT / VERIFY ALDL INTERFACE 
+	// =======================================================
 
 	// Establish a connection to the aldl
 	// ===================================
@@ -131,16 +131,27 @@ int main(int argc, const char* argv[]){
 		return -1;
 	}
 
-	// set the custom baud rate:
-	// the ALDL interface operates at 8192. it would be preferable to get as close to this
-	// baud rate as possible. if it cannot be set; it should still work at the standard
-	// baud rate of 9600; the framing errors aren't excessive enough to cause problems,
-	// and will be caught by bad checksums.
+	/* Set custom baud rate:
+	   ALDL has two variants; 
+	     1) 160 baud with non-RS232 framing.  Clock up to 1600 baud
+	        and take one byte from each bit to get us the 8 data bits
+		plus one start and one stop bit.
+	     2) 8192 baud with RS232 framing.
+
+	   Prefer to set exact baud rate if possible, but they are non-standard
+	   PC datarates..
+
+	   8192 should work at 9600; the packets are short enough that framing
+	   errors should be minimal and checksums will catch them anyway.
+	*/
+
+	aldl_settings.customrate = 1;
 	if (set_custom_baud_rate(aldl_settings.faldl, aldl_settings.definition->ideal_baudrate)!=0) {
 		fprintf(stderr," Couldn't set baud rate to %d. Using standard rate (%d).\n",
 			aldl_settings.definition->ideal_baudrate,
 			aldl_settings.definition->basic_baudrate);
 		fprintf(stderr," There may be framing errors.\n");
+		aldl_settings.customrate = 0;
 	}
 	
 	// verify the aldl
@@ -175,9 +186,9 @@ int main(int argc, const char* argv[]){
 	}
 
 
-	// ========================================================================
-	// 				CLEANUP (FLUSH SERIAL LINE, CLOSE PORT) 
-	// ========================================================================
+	// ============================================================
+	// 		CLEANUP (FLUSH SERIAL LINE, CLOSE PORT) 
+	// ============================================================
 
 	// discard any unwritten data
 	tcflush(aldl_settings.faldl, TCIOFLUSH);
@@ -253,7 +264,7 @@ int send_aldl_message(char* msg_buf, unsigned int size)
 // so that mode 8 isn't even required.
 int get_mode1_message(char* inbuffer, unsigned int size)
 {
-	int res;
+	int res = 0;
 	char outbuffer[__MAX_REQUEST_SIZE]; // max request size defined in linuxaldl_definitions.h
 
 	aldl_definition* def = aldl_settings.definition;
@@ -287,6 +298,7 @@ int get_mode1_message(char* inbuffer, unsigned int size)
 				  seq, 3, 0, 
 				  aldl_settings.scan_timeout*1000);
 	} else {
+		/* Wait for Framing START ? */
 		// XXX what sequence to match for 160baud rate?
 	}
 

src/linuxaldl.h

@@ -120,7 +120,7 @@ typedef struct _linuxaldl_definition {
 									// message is the 4th byte onward, this should be 3. (1+3 = 4)
 
 	byte_def_t* mode1_def; // pointer to start of table of byte_def_t structs.
-							// the last element must be LINUXALDL_MODE1_END_DEF
+			       // the last element must be LINUXALDL_MODE1_END_DEF
 
 	char mode8_request[__MAX_REQUEST_SIZE];  // the mode 8 (silence) request message, incl checksum
 	unsigned int mode8_request_length;  // the length of the mode 8 message incl checksum
@@ -141,31 +141,32 @@ typedef struct _linuxaldl_settings
 {
 	/* Configuration fields */
 	const char* aldlportname; // path to aldl interface port
-	const char* logfilename; 	// filename for the log file
-	const char* aldldefname; // name for the ALDL definition to be used
+	const char* logfilename;  // filename for the log file
+	const char* aldldefname;  // name for the ALDL definition to be used
 
 	unsigned int scan_interval; // msec between scan requests
 	unsigned int scan_timeout; // msec to timeout on scan request.
-				// note that read-sequence takes timeout in usec.				// usec = msec*1000
+				// note that read-sequence takes timeout in usec.
+				// usec = msec*1000
 
 	/* Data definitions */
 	aldl_definition** aldl_definition_table; // array of pointers to data definitions. (see linuxaldl_definitions.h)
 	
 	/* Runtime stuff */
-	int faldl; 			// aldl serial interface file descriptor
+	int customrate;         // 1 if we are using accurate datarate.
+	int faldl; 		// aldl serial interface file descriptor
 	int flogfile; 		// file descriptor for log file
-	int scanning; // 1 when the timer has been set for making scans, otherwise 0.
+	int scanning; 		// 1 when the timer has been set for making scans, otherwise 0.
 	aldl_definition* definition; // see linuxaldl_definitions.h
 
 	char* data_set_raw;	// the current/most recent set of data from a mode1 message.
 				// this is allocated when a definition is selected
 
-	char** data_set_strings;	// pointer to array of data set in string format.
-					// allocated when a definition is selected in the GUI
-
-	float* data_set_floats;		// data set in float format
-					// allocated when a definition is selected in the GUI
+	char** data_set_strings;// pointer to array of data set in string format.
+				// allocated when a definition is selected in the GUI
 
+	float* data_set_floats;	// data set in float format
+				// allocated when a definition is selected in the GUI
 } linuxaldl_settings;
 
 // function prototypes

src/linuxaldl_definitions.h

@@ -255,7 +255,7 @@ aldl_definition aldl_9A = { .mask = "9A",
 			    .mode1_data_offset = 1,
 			    .mode1_def = aldl_9A_mode1,
 			    .basic_baudrate = B4800,
-			    .ideal_baudrate = 160,
+			    .ideal_baudrate = 1600,   /* ie basic baud rate / 3 */
 };
 
 /* Definition table */