V4.0.4

docs/changelog.md

@@ -1,5 +1,10 @@
 # Changelog for dw-link
 
+## Version 4.0.4
+- Changes in platform.ini files
+- Change: Giving a more informative error message when the stuck-at-1
+  error is diagnosed because of capacitive load on the reset line 
+
 ## Version 4.0.3 (03-Jan-2025)
 
 - ISP programming got a watch dog timer so that after a wrong choice the debugger will recover after 4 seconds

docs/manual.md

@@ -556,16 +556,16 @@ Finally, there are commands that control the settings of the debugger and the MC
 | monitor dwire [+\|-]               | **+** activate debugWIRE; **-** disables debugWIRE; without any argument, it will report MCU type and whether debugWIRE is enabled (*) |
 | monitor reset                      | resets the MCU (*)                                           |
 | monitor mcu [*mcu-name*]           | If no argument is given, the MCU dw-link is connected to is printed. Otherwise, it is checked whether the given *mcu-name* matches the connected MCU and if not, a fatal error (5) is signaled. |
-| monitor ckdiv [1\|8]               | **1** unprograms the CKDIV8 fuse, **8** programs it; without an argument, the state of the fuse is reported (*) |
-| monitor oscillator [r\|a\|x\|e\|s] | set clock source to **r**c osc., **a**lternate rc osc., **x**tal, **e**xternal osc., or **s**low osc. (128 kHz); without argument, it reports the fuse setting (*) |
-| monitor breakpoint [h\|s]          | set number of allowed breakpoints to 1, when **h**ardware breakpoint only, or 25, when also **s**oftware breakpoints are permitted; without argument it reports setting |
-| monitor speed [l\|h]               | set communication speed limit to **l**ow (=150kbps) or to **h**igh (=300kbps); without an argument, the current communication speed and limit is printed |
+| monitor ckdiv [1\|8]               | **1** unprograms the CKDIV8 fuse, **8** programs it; without an argument, the state of the fuse is reported (*+) |
+| monitor oscillator [r\|a\|x\|e\|s] | set clock source to **r**c osc., **a**lternate rc osc., **x**tal, **e**xternal osc., or **s**low osc. (128 kHz); without argument, it reports the fuse setting (*+) |
+| monitor breakpoint [h\|s]          | set the number of allowed breakpoints to 1, when **h**ardware breakpoint only, or 25, when also **s**oftware breakpoints are permitted; without argument, it reports setting |
+| monitor speed [l\|h]               | set the communication speed limit to **l**ow (=150kbps) or to **h**igh (=300kbps); without an argument, the current communication speed and speed limit is printed |
 | monitor singlestep [s\|u]          | Sets single stepping to **s**afe (no interrupts) or **u**nsafe (interrupts can happen); without an argument, it reports the state |
-| monitor lasterror                  | print error number of last fatal error                       |
-| monitor flashcount                 | reports on how many flash-page write operation have taken place since start |
+| monitor lasterror                  | print error number of the last fatal error                   |
+| monitor flashcount                 | reports on how many flash-page write operations have taken place since the start |
 | monitor timeouts                   | report number of timeouts (should be 0!)                     |
 
-All of the commands marked with (*) reset the MCU.
+All of the commands marked with (*) reset the MCU. The ones marked with (+) need to take the MCU out of the debugWIRE mode and afterwards in again. 
 
 <a name="section67"></a>
 
@@ -1068,8 +1068,9 @@ Error #  | Meaning
 2 | Connection error: MCU type is not supported
 3 | Connection error: Lock bits or BOOTRST could not be cleared 
 4 | Connection error: MCU has PC with stuck-at-one bits 
-5 | MCU type does not match 
-6 | Unknown connection error 
+5 | Connection error: Reset line has a capacitive load 
+6 | MCU type does not match 
+7 | Unknown connection error 
 101 | No free slot in breakpoint table
 102 | Packet length too large
 103 | Wrong memory type
@@ -1197,7 +1198,7 @@ Initial version
 * New fatal error: Wrong MCU type (caused by monitor mcu command)
 * Renamed fatal error 3
 * The *boards manager URLs* have changed: a suffix `_plus_Debug` has been added to the core name.
-* Simplified paltoformIO.ini
+* Simplified platoformio.ini
 * Corrected statement about the meaning of BREAK when the debugger is not active
 * `monitor mcu` command listed
 * Description of how to use the AutoDW jumper added 
@@ -1206,3 +1207,4 @@ Initial version
 * Added notes that you cannot debug the UNO, but need to select ATmega328
 * Added notes about the target board and potentially using external powering
 * Edited the problem description for locked up hardware debugger/serial line
+* New fatal error: capacitive load on the reset line

dw-link/dw-link.ino

@@ -127,8 +127,9 @@
 #define CONNERR_UNSUPPORTED_MCU 2 // connection error: MCU not supported
 #define CONNERR_LOCK_BITS 3 // connection error: lock bits are set
 #define CONNERR_STUCKAT1_PC 4 // connection error: MCU has PC with stuck-at-one bits
-#define CONNERR_WRONG_MCU 5 // wrong MCU (detected by monitor mcu command)
-#define CONNERR_UNKNOWN 6 // unknown connection error
+#define CONNERR_CAPACITIVE_LOAD 5 // connection error: Reset has a capacitive load
+#define CONNERR_WRONG_MCU 6 // wrong MCU (detected by monitor mcu command)
+#define CONNERR_UNKNOWN 7 // unknown connection error
 #define NO_FREE_SLOT_FATAL 101 // no free slot in BP structure
 #define PACKET_LEN_FATAL 102 // packet length too large
 #define WRONG_MEM_FATAL 103 // wrong memory type
@@ -1099,11 +1100,21 @@ boolean gdbConnect(boolean verbose)
   DEBLN(conncode);
   if (conncode == 1) {
 #if STUCKAT1PC
-    mcu.stuckat1byte = (DWgetWPc(false) & ~((mcu.flashsz>>1)-1))>>8;
-    //DEBPR(F("stuckat1byte=")); DEBLNF(mcu.stuckat1byte,HEX);
+    if (mcu.sig == 0x9205 || mcu.sig == 0x930A) {
+      mcu.stuckat1byte = (DWgetWPc(false) & ~((mcu.flashsz>>1)-1))>>8;
+      DEBPR(F("stuckat1byte=")); DEBLNF(mcu.stuckat1byte,HEX);
+    } else {
+      conncode = -5;
+    }
 #else
     mcu.stuckat1byte = 0;
-    if (DWgetWPc(false) > (mcu.flashsz>>1)) conncode = -4;
+    if (DWgetWPc(false) > (mcu.flashsz>>1)) {
+      if  (mcu.sig == 0x9205 || mcu.sig == 0x930A) {
+	conncode = -4;
+      } else {
+	conncode = -5;
+      }
+    }
 #endif
   }
   if (conncode == 1) {
@@ -1121,6 +1132,7 @@ boolean gdbConnect(boolean verbose)
   case -2: gdbDebugMessagePSTR(PSTR("***Cannot connect: Unsupported MCU"),-1); break;
   case -3: gdbDebugMessagePSTR(PSTR("***Cannot connect: Lock bits are set"),-1); break;
   case -4: gdbDebugMessagePSTR(PSTR("***Cannot connect: PC with stuck-at-one bits"),-1); break;
+  case -5: gdbDebugMessagePSTR(PSTR("***Cannot connect: Reset line has a capacitive load"),-1); break;
   default: gdbDebugMessagePSTR(PSTR("***Cannot connect for unknown reasons"),-1); conncode = -CONNERR_UNKNOWN; break;
   }
   if (verbose) {

examples/pio-varblink/platformio.ini

@@ -11,26 +11,30 @@
 default_envs = debug
 
 [env:debug]
-extends = env:attiny85                     ;; <--- substitute the right board here
+extends = env:attiny85            ;; <--- substitute the right board here
 build_type = debug
 debug_tool = custom
-;;debug_port = /dev/cu.usbmodem211101      ;; <-- specify instead of debug_server with correct serial line
-debug_server = /usr/local/bin/dw-server.py  
-    -p 3333   ;; <-- specify instead of debug_port
+;;debug_port = /dev/cu.usbmodem01 ;; <-- specify instead of debug_server with correct serial line
+debug_server = /usr/local/bin/dw-server.py  ;; <-- specify instead of debug_port
+    -p 3333   
 debug_init_cmds = 
     define pio_reset_halt_target
-		monitor reset
-	end
-	set serial baud 115200
+         monitor reset
+    end
+    define pio_reset_run_target
+         monitor reset
+	 continue
+    end
+    set serial baud 115200
     target remote $DEBUG_PORT
-	monitor version
-	monitor mcu
-	$LOAD_CMDS
-	$INIT_BREAK
+    monitor version
+    monitor mcu
+    $LOAD_CMDS
+    $INIT_BREAK
 debug_build_flags = 
-	-Og
-	-g3
-	-fno-lto
+    -Og
+    -g3
+    -fno-lto
 
 [env:attiny85]
 platform = atmelavr