diff --git a/flashloaders/stm32l0x.s b/flashloaders/stm32l0x.s
index 9fc44468f..6c863c64a 100644
--- a/flashloaders/stm32l0x.s
+++ b/flashloaders/stm32l0x.s
@@ -34,8 +34,8 @@
     .global write
 
 /*
-    r0 - destination address
-    r1 - source address
+    r0 - source address
+    r1 - destination address
     r2 - count
 */
 
@@ -46,9 +46,9 @@
 
 write_word:
     // Load one word from address in r0, increment by 4
-    ldr    r4, [r1]
+    ldr    r4, [r0]
     // Store the word to address in r1, increment by 4
-    str    r4, [r0]
+    str    r4, [r1]
     // Increment r3
     adds    r3, #1
 	adds	r1, #4
diff --git a/flashloaders/stm32lx.s b/flashloaders/stm32lx.s
index 799d1345c..764594d9c 100644
--- a/flashloaders/stm32lx.s
+++ b/flashloaders/stm32lx.s
@@ -34,8 +34,8 @@
     .global write
 
 /*
-    r0 - destination address
-    r1 - source address
+    r0 - source address
+    r1 - destination address
     r2 - count
 */
 
@@ -46,9 +46,9 @@
 
 write_word:
     // Load one word from address in r0, increment by 4
-    ldr.w    ip, [r1], #4
+    ldr.w    ip, [r0], #4
     // Store the word to address in r1, increment by 4
-    str.w    ip, [r0], #4
+    str.w    ip, [r1], #4
     // Increment r3
     adds    r3, #1
 
diff --git a/src/stlink-common.c b/src/stlink-common.c
index 5fbf57542..01ce06c6f 100644
--- a/src/stlink-common.c
+++ b/src/stlink-common.c
@@ -1501,8 +1501,8 @@ int write_loader_to_sram(stlink_t *sl, stm32_addr_t* addr, size_t* size) {
     static const uint8_t loader_code_stm32l[] = {
 
         /* openocd.git/contrib/loaders/flash/stm32lx.S
-           r0, input, dest addr
-           r1, input, source addr
+           r0, input, source addr
+           r1, input, dest addr
            r2, input, word count
            r3, output, word count
            */
@@ -1510,8 +1510,8 @@ int write_loader_to_sram(stlink_t *sl, stm32_addr_t* addr, size_t* size) {
         0x00, 0x23,
         0x04, 0xe0,
 
-        0x51, 0xf8, 0x04, 0xcb,
-        0x40, 0xf8, 0x04, 0xcb,
+        0x50, 0xf8, 0x04, 0xcb,
+        0x41, 0xf8, 0x04, 0xcb,
         0x01, 0x33,
 
         0x93, 0x42,
@@ -1522,8 +1522,8 @@ int write_loader_to_sram(stlink_t *sl, stm32_addr_t* addr, size_t* size) {
     static const uint8_t loader_code_stm32l0[] = {
 
         /*
-           r0, input, dest addr
-           r1, input, source addr
+           r0, input, source addr
+           r1, input, dest addr
            r2, input, word count
            r3, output, word count
          */
@@ -1531,8 +1531,8 @@ int write_loader_to_sram(stlink_t *sl, stm32_addr_t* addr, size_t* size) {
         0x00, 0x23,
         0x04, 0xe0,
 
-        0x0c, 0x68,
-        0x04, 0x60,
+        0x04, 0x68,
+        0x0c, 0x60,
         0x01, 0x33,
         0x04, 0x31,
         0x04, 0x30,
@@ -2064,7 +2064,7 @@ int stlink_fwrite_flash(stlink_t *sl, const char* path, stm32_addr_t addr) {
 int run_flash_loader(stlink_t *sl, flash_loader_t* fl, stm32_addr_t target, const uint8_t* buf, size_t size) {
 
     reg rr;
-    int target_reg, source_reg, i = 0;
+    int i = 0;
     size_t count;
 
     DLOG("Running flash loader, write address:%#x, size: %zd\n", target, size);
@@ -2075,19 +2075,13 @@ int run_flash_loader(stlink_t *sl, flash_loader_t* fl, stm32_addr_t target, cons
         return -1;
     }
 
-    if (sl->flash_type == FLASH_TYPE_L0) {
-        count = size / sizeof(uint32_t);
-        if (size % sizeof(uint32_t))
-            ++count;
-        target_reg = 0;
-        source_reg = 1;
-    } else if (sl->flash_type == FLASH_TYPE_F0) {
+    if (sl->flash_type == FLASH_TYPE_F0) {
         count = size / sizeof(uint16_t);
         if (size % sizeof(uint16_t))
             ++count;
-        target_reg = 1;
-        source_reg = 0;
-    } else if (sl->flash_type == FLASH_TYPE_F4 || sl->flash_type == FLASH_TYPE_L4) {
+    } else if (sl->flash_type == FLASH_TYPE_F4 ||
+            sl->flash_type == FLASH_TYPE_L4 ||
+            sl->flash_type == FLASH_TYPE_L0) {
         count = size / sizeof(uint32_t);
         if (size % sizeof(uint32_t))
             ++count;
@@ -2095,16 +2089,14 @@ int run_flash_loader(stlink_t *sl, flash_loader_t* fl, stm32_addr_t target, cons
             if (count % 2)
                 ++count;
         }
-        target_reg = 1;
-        source_reg = 0;
     } else {
         fprintf(stderr, "unknown coreid 0x%x, don't know what flash loader to use\n", sl->core_id);
         return -1;
     }
 
     /* setup core */
-    stlink_write_reg(sl, fl->buf_addr, source_reg); /* source */
-    stlink_write_reg(sl, target, target_reg); /* target */
+    stlink_write_reg(sl, fl->buf_addr, 0); /* source */
+    stlink_write_reg(sl, target, 1); /* target */
     stlink_write_reg(sl, count, 2); /* count */
     stlink_write_reg(sl, 0, 3); /* flash bank 0 (input), only used on F0, but armless fopr others */
     stlink_write_reg(sl, fl->loader_addr, 15); /* pc register */