LED blinks once, camera does not power on (SX280)

q1144529

9

« on: 14 / April / 2019, 17:46:28 »

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I have the SX280 and have been running CHDK on it fine (beta 1.5.0-5160).

With the camera turned off, I accidentally dropped it. A few minutes later I tried turning it on and all I get is the little green LED on the back blinks once.

If I remove the SD card or switch it to read/write, I do not even get an LED blink. Nothing at all happens. Any ideas what might be wrong? The camera looks cosmetically perfect.

Thanks in advance for any help you can provide.

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waterwingz

12140

Re: LED blinks once, camera does not power on (SX280)

« Reply #1 on: 14 / April / 2019, 17:53:07 »

So if CHDK is enabled, you get an LED blink. That's encouraging.

If you boot with the SD card lock off (R/W enable), what happens if you press the shutter button? Maybe it's just the LCD display that has come loose.

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Ported : A1200 SD940 G10 Powershot N G16

reyalp

14118

Re: LED blinks once, camera does not power on (SX280)

« Reply #2 on: 14 / April / 2019, 17:59:25 »

Quote from: q1144529 on 14 / April / 2019, 17:46:28

With the camera turned off, I accidentally dropped it. A few minutes later I tried turning it on and all I get is the little green LED on the back blinks once.

The blink when CHDK is present likely means the camera boots, detects some error and shuts down.

Given that this appears to have been caused by a fall, it's virtually certain to be a hardware fault that requires physical repair. You might be able to get some information about the nature of the fault using a custom CHDK build (write the romlog somewhere in the boot process), but unless you are planning to attempt a repair, there's not much point.

You should check waterwingz idea about the LCD, but I think without CHDK, the LED would still be expected to blink a few times at startup.

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Don't forget what the H stands for.

srsa_4c

4451

Re: LED blinks once, camera does not power on (SX280)

« Reply #3 on: 14 / April / 2019, 18:40:32 »

The luckiest kind of hw fault that could cause this is a broken battery door switch.
I get a single blink on my sx280 if I attempt to start it with battery door open (using a locked card with CHDK).

I attached special builds for 102b and 102c/102d that should allow starting the cam with the door open. This will of course not help if something else is broken.

Used the following patch and built with OPT_RUN_WITH_BATT_COVER_OPEN=1

Code: [Select]

Index: platform/sx280hs/sub/102b/boot.c
===================================================================
--- platform/sx280hs/sub/102b/boot.c	(revision 5167)
+++ platform/sx280hs/sub/102b/boot.c	(working copy)
@@ -415,6 +415,9 @@
     "bl      sub_fc20d304\n"
     "bl      sub_fc0ba81c\n"
     "bl      sub_fc095750\n"
+
+    "bl      busy_loop\n"
+
     "bl      sub_fc12ed44\n"
     "bl      sub_fc095b24\n"
     "bl      sub_fc09594a\n"
@@ -429,6 +432,17 @@
     );
 }
 
+void __attribute__((naked,noinline)) busy_loop() {  // loop hack that allows startup with battery door open
+  asm volatile (
+"   LDR     R0, =0x400000 \n"
+"loop1: \n"
+"   nop\n"
+"   SUBS    R0,R0,#1 \n"
+"   BNE     loop1 \n"
+"   bx      lr\n"
+    );
+}
+
 //taskcreate_physw
 void __attribute__((naked,noinline)) sub_fc06021a_my() {
     asm volatile (
Index: platform/sx280hs/sub/102c/boot.c
===================================================================
--- platform/sx280hs/sub/102c/boot.c	(revision 5167)
+++ platform/sx280hs/sub/102c/boot.c	(working copy)
@@ -416,6 +416,9 @@
     "bl      sub_fc20d318\n"
     "bl      sub_fc0ba81c\n"
     "bl      sub_fc095750\n"
+
+    "bl      busy_loop\n"
+
     "bl      sub_fc12ed44\n"
     "bl      sub_fc095b24\n"
     "bl      sub_fc09594a\n"
@@ -430,6 +433,17 @@
     );
 }
 
+void __attribute__((naked,noinline)) busy_loop() {  // loop hack that allows startup with battery door open
+  asm volatile (
+"   LDR     R0, =0x400000 \n"
+"loop1: \n"
+"   nop\n"
+"   SUBS    R0,R0,#1 \n"
+"   BNE     loop1 \n"
+"   bx      lr\n"
+    );
+}
+
 //taskcreate_physw
 void __attribute__((naked,noinline)) sub_fc06021a_my() {
     asm volatile (

CHDK-sx280hs-102b-1.5.0-5166_batterydoorhack.zip (257.76 kB - downloaded 24 times.)

CHDK-sx280hs-102c-1.5.0-5166_batterydoorhack.zip (257.82 kB - downloaded 20 times.)

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q1144529

9

Re: LED blinks once, camera does not power on (SX280)

« Reply #4 on: 15 / April / 2019, 15:20:25 »

Thank you so much. It was the battery door switch. I poked a pin in it and now it seems to permanently think the switch is in the shut position. :-D

I will keep the special builds you uploaded just in case my needle fix stops working.

Since you've saved me £60, do you have any preferred charity I can donate to on your behalf?

« Last Edit: 15 / April / 2019, 16:31:29 by q1144529 »

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