From 6a2e8164d9ef44fcf7c750ad376646712d371449 Mon Sep 17 00:00:00 2001
From: true <trueserve@users.noreply.github.com>
Date: Wed, 1 Nov 2023 10:15:18 -0700
Subject: [PATCH] Fix flash routine bugs, make it work

---
 include/flash.h |  2 +-
 src/flash.c     | 53 ++++++++++++++++++++++++++++++++++++++-----------
 src/main.c      |  2 ++
 src/probe.c     | 27 ++++++++++++++++---------
 4 files changed, 62 insertions(+), 22 deletions(-)

diff --git a/include/flash.h b/include/flash.h
index 2db7bd6..a74b1cc 100644
--- a/include/flash.h
+++ b/include/flash.h
@@ -34,7 +34,7 @@ typedef struct UConf {
 	uint16_t diode_shorted;			// unused, unneeded
 	uint32_t rsvd_1[4];
 	uint32_t rsvd_2[8];
-	uint32_t vctr;					// increment every update of config
+	uint32_t update_cntr;			// increment every update of config
 	uint32_t crc32;					// CRC of preceding 60 bytes
 } UConf;							// 64 bytes
 
diff --git a/src/flash.c b/src/flash.c
index 373b3d4..d00f48c 100644
--- a/src/flash.c
+++ b/src/flash.c
@@ -274,21 +274,14 @@ void flash_commit_conf()
         }
     }
 
-    // if all pages are occupied, erase the first page
+    // if all pages are occupied, we'll erase all the pages
     if (i == UCONF_COUNT) {
         flash_full = 1;
     }
 
-    // copy flash page from ROM to the write buffer,
-    // as our data (64 bytes) is smaller than the page write size (128 bytes)
-    f32 = (uint32_t *)fconf;
-    u32 = (uint32_t *)write;
-    for (i = 0; i < (FLASH_PAGE_SIZE / 4); i++) {
-        *u32++ = *f32++;
-    }
-
-    // ensure config header is correct, and calculate CRC
+    // ensure live config header is correct, and calculate CRC
     conf.conf_key = UCONF_KEY;
+    conf.update_cntr++;
     u32 = (uint32_t *)&conf;
     
     CRC->CR = CRC_CR_RESET;
@@ -298,14 +291,50 @@ void flash_commit_conf()
         CRC->DR = u32[i];
     }
     u32[(UCONF_SIZE / 4) - 1] = CRC->DR;
+    
+    // do we need to actually update data?
+    // check checksum of our data against checksum of prior entry
+    if (flash_idx) {
+        fconf = (struct UConf *)(UCONF_FLASH_START + (UCONF_SIZE * (flash_idx - 1)));
+        if (fconf->crc32 == conf.crc32) {
+            // nothing to update; we can break out
+            return;
+        }
+    }
+
+    // set empty write buffer to 0xff
+    for (i = 0; i < 32; i++) {
+        write[i] = 0xffffffff;
+    }
+
+    // set write buffer
+    u32 = (uint32_t *)write;
+
+    // if this is the second entry in a flash page,
+    // copy first half of flash page from ROM to the write buffer,
+    // as our config size (64 bytes) is smaller than the page write size (128 bytes)
+    if (flash_idx & 1) {
+        f32 = (uint32_t *)fconf;
+        for (i = 0; i < (UCONF_SIZE / 4); i++) {
+            *u32++ = *f32++;
+        }
+    }
+
+    // correct flash_idx if it is out of bounds
+    // (we will usually have 1-8, only getting 0 on the very first write)
+    if (flash_idx == UCONF_COUNT) {
+        flash_idx = 0;
+    }
 
     // copy user config from RAM to write buffer at the appropriate offset
     f32 = (uint32_t *)&conf;
-    u32 = (uint32_t *)write;
-    for (i = (flash_idx ? UCONF_SIZE : 0); i < (UCONF_SIZE / 4); i++) {
+    for (i = 0; i < (UCONF_SIZE / 4); i++) {
         *u32++ = *f32++;
     }
 
+    // we now need the flash page boundary, so remove lowest bit from flash_idx
+    flash_idx &= ~1;
+
     // erase this page
     flash_erase_page(UCONF_FLASH_START + (UCONF_SIZE * flash_idx));
 
diff --git a/src/main.c b/src/main.c
index d346238..b067fdd 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2,6 +2,8 @@
  * main.c: test-o continuity and diode tester
  *
  * your robot addon badge buddy for testing all the things
+ * 
+ * version 0.0.1
  *
  * file creation: 20231015 0021
  */
diff --git a/src/probe.c b/src/probe.c
index 862554a..22cd925 100644
--- a/src/probe.c
+++ b/src/probe.c
@@ -207,7 +207,7 @@ void probe_measure()
 
 	switch (mode) {
 		case MODE_CONT:		probe_measure_cont(); break;
-		case MODE_FUN:		break;	// todo: run RGBLED program
+		case MODE_FUN:		break;		// LED program is run elsewhere
 		case MODE_DIODE:	probe_measure_diode(); break;
 	}
 }
@@ -218,13 +218,22 @@ void probe_measure()
  */
 void probe_mode_switch(uint8_t mode)
 {
-	if (mode == MODE_CONT) {
-		// set LED to buzzer mode, set PROBESEL low
-		led_mode_buzzer();
-		PROBESEL_PORT->BRR  = (1 << PROBESEL_PIN);
-	} else {
-		// set LED to dual RGB mode, set PROBESEL high
-		led_mode_rgb();
-		PROBESEL_PORT->BSRR = (1 << PROBESEL_PIN);
+	switch (mode) {
+		case MODE_CONT: {
+			// set LED to buzzer mode, set PROBESEL low
+			led_mode_buzzer();
+			PROBESEL_PORT->BRR  = (1 << PROBESEL_PIN);
+			break;
+		}
+		default: {
+			// set LED to dual RGB mode, set PROBESEL high
+			led_mode_rgb();
+			PROBESEL_PORT->BSRR = (1 << PROBESEL_PIN);
+		}
+	}
+
+	// save config if moving into LED mode
+	if (mode == MODE_FUN) {
+		flash_commit_conf();
 	}
 }
\ No newline at end of file