add function to initialize Flash

1 files changed, 45 insertions, 5 deletions

diff --git a/globals.c b/globals.c
index 8324fed..66007d3 100644
--- a/globals.c
+++ b/globals.c
@@ -2,11 +2,51 @@
 
 GlobalStruct globals = {
 	.ChannelState = {0.0},
-	.Flash = {	.flash_start = (char) 99,
-			.aux_error_message="FIXME",
-			.channels = (short) 1, 
-			.enable_avrq_extra_ampls = (char) 12, 
-			.ChanKey_frequency = (char) 0  },
 	.error_queue = {0},
 	.number_of_errors = 0
 };
+
+
+int readUserBlock(void)
+{
+	// read the flash.copy file into the globals.Flash struct
+	// and return the number of bytes read in
+
+	// if the file does not exist, then "return 0";
+	return 0;
+}
+
+void writeUserBlock(int addr, int numbytes)
+{
+	// check if flash.copy file exists
+	// - if it does, update the requested address and
+	//   number of bytes
+
+	// - if does not, create the file and
+	//   set addr = 0, numbytes = sizeof (mem)
+	//   so that entire struct will be written,
+	//   instead of just the requested range
+
+	// All writing should be done in a super-safe 
+	// way. Non-corruption, even during a power-off transient,
+	// is the priority here. We do not want instruments
+	// losing configuration data ever, because that
+	// means expensive repairs.
+}
+
+void initFlash(void)
+{
+	if (readUserBlock() > 0) return;
+
+	// uninitialized device!
+	globals.Flash.flash_start = (char) 99;
+	strcpy(globals.Flash.aux_error_message,"FIXME");
+	globals.Flash.channels = (short) 1;
+	globals.Flash.enable_avrq_extra_ampls = (char) 12;
+	globals.Flash.ChanKey_frequency = (char) 0;
+
+	// save the default Flash config, for nonvolatile persistence
+	writeUserBlock(0, sizeof(globals.Flash));
+}
+
+