Hi.
I'm posting this here in part as a memo to self as well as to describe the procedure I used in case anyone else found it useful. I found a lot of the necessary information to make this work on this forum and I figured I would give something back. If this is not the appropriate place to post this, I don't mind it being deleted but I hope it can help other people.
I got an admin password locked HP Elitebook 840 G5 recently that I wanted to unlock. I'm a relative newcomer to reprogramming and unlocking firmware. The only previous experience I had was unlocking a BIOS locked thin client using a CH314a programmer and SOIC8 programming clip. Unfortunately the Elitebook 840 G5 BIOS and EC are in WSON8 package. Here's a photo of the ones that were on my mainboard.
I wasn't really planning to get a reflow station just to sort this out so I had resigned myself to probably having to solder wires to the legs or test pads and do the programming that way. I was aware that some people had used pogo pin test probes however I was wary of having to hold them for several minutes pressed to the board while the chip gets read and then upload the unlocked firmware. Not a great plan. Nevertheless I _really_ wanted to try and see if there was a way to do it without having to do any soldering or unsoldering if possible.
I did some research online and I came upon the following post by Mark B., where he outlined his DIY SOIC8 pogo-pin-adapter. Included in the short post was also the openSCAD source code for the spacerplate that he designed to mount pogo pins on for his DIY adapter. Based on his design I adapted his spacerplate for my specific case. Since both the BIOS and EC chips have test pads, I figured I could make my own spacerplate with a 3-d printer and then mount the pogo pins on it. I got a set of 100 P75-B1 pogo pins on Amazon for about 4-5 Eur to experiment with and set to work. I first went with his original design slightly altered (changed the distance between the two rows of holes to 7.5 mm so the pins would sit in the middle of the test pads), however it didn't work out well because hole sizes for the pogo pins had to be enlarged from 1 mm to 1.2 mm when printing the spacerplate with a 3d printer (Ender 3 with a 0.4 mm nozzle, 0.12 mm layer height) as opposed to milled with a micro-milling machine, which would lead to them overlapping (due to the pitch distance on the chips and test pads being 1.27 mm). To solve this I staggered them in a zig-zag pattern, which solved the issue and the holes came out distinctly separate with no overlapping. I then pushed the pogo pins trough and used a bit of super glue to fix them in place. Following that I used some jumper wires to connect the pogo pins to the CH314a programmer. You will have to remove the plastic socket on the female side of the jumper wires and leave only the metal internal socket, connect them to the pogo pins and then use just one layer wrap of electrical isolation tape to prevent the terminals from touching. You can then put some hot glue on the whole lot to make it firmer, but I didn't in case I needed to redo any of the terminals. I additionally made the spacerplate slightly longer for support and found a stl file for a 3d printed clip by mjf55, which I very haphazardly adapted for my use in order to hold the pogo pin probe pressed down during programming. You can find a photo of the whole jury rigged adapter below.
As you can see, the whole thing is janky, but it worked. It held the pogo pin adapter in place, and after a bit of fiddling I managed to get a firm electrical connection, read the locked EC firmware (in three copies just to make sure there were no reading errors), unlocked it with RCUnlocker, flashed the unlocked firmware, reset the security settings to default and hey presto, the job was done.
I'm adding the openSCAD code for my modified spacerplate below, as well as the stl files for the spacerplate and clip. It's quite probable you will have to do some fiddling with the openSCAD code to make the holes the proper size when printing on your printer (I tried 1 to 1.25 mm in 0.05 mm increments and settled in the end on 1.2 mm). Or you can try the stl file directly and see if it fits your need.
Pogo_pin_Adapter_3d_print_files.zip
Some pointers:
-You have to be careful as you handle the pogo pin adapter when placing it into the clip and pressing on the test pads. You don't want to scratch or damage any electronics parts or the pogo pins. Go slow and use some foam underneath the clip just in case to prevent damage.
-You'll have to carefully align the pins to the test pads, use a magnifying glass or phone camera on zoom to check and adjust carefully if necessary. Patience is needed.
-I included just the spacer plate for the EC chip, but you can easily modify the openSCAD file to increase the distance between the two rows of pins to fit the BIOS chip test pads, you can find a portable version on openSCAD on their website, so you don't even need to install it.
I'm posting this here in part as a memo to self as well as to describe the procedure I used in case anyone else found it useful. I found a lot of the necessary information to make this work on this forum and I figured I would give something back. If this is not the appropriate place to post this, I don't mind it being deleted but I hope it can help other people.
I got an admin password locked HP Elitebook 840 G5 recently that I wanted to unlock. I'm a relative newcomer to reprogramming and unlocking firmware. The only previous experience I had was unlocking a BIOS locked thin client using a CH314a programmer and SOIC8 programming clip. Unfortunately the Elitebook 840 G5 BIOS and EC are in WSON8 package. Here's a photo of the ones that were on my mainboard.
I wasn't really planning to get a reflow station just to sort this out so I had resigned myself to probably having to solder wires to the legs or test pads and do the programming that way. I was aware that some people had used pogo pin test probes however I was wary of having to hold them for several minutes pressed to the board while the chip gets read and then upload the unlocked firmware. Not a great plan. Nevertheless I _really_ wanted to try and see if there was a way to do it without having to do any soldering or unsoldering if possible.
I did some research online and I came upon the following post by Mark B., where he outlined his DIY SOIC8 pogo-pin-adapter. Included in the short post was also the openSCAD source code for the spacerplate that he designed to mount pogo pins on for his DIY adapter. Based on his design I adapted his spacerplate for my specific case. Since both the BIOS and EC chips have test pads, I figured I could make my own spacerplate with a 3-d printer and then mount the pogo pins on it. I got a set of 100 P75-B1 pogo pins on Amazon for about 4-5 Eur to experiment with and set to work. I first went with his original design slightly altered (changed the distance between the two rows of holes to 7.5 mm so the pins would sit in the middle of the test pads), however it didn't work out well because hole sizes for the pogo pins had to be enlarged from 1 mm to 1.2 mm when printing the spacerplate with a 3d printer (Ender 3 with a 0.4 mm nozzle, 0.12 mm layer height) as opposed to milled with a micro-milling machine, which would lead to them overlapping (due to the pitch distance on the chips and test pads being 1.27 mm). To solve this I staggered them in a zig-zag pattern, which solved the issue and the holes came out distinctly separate with no overlapping. I then pushed the pogo pins trough and used a bit of super glue to fix them in place. Following that I used some jumper wires to connect the pogo pins to the CH314a programmer. You will have to remove the plastic socket on the female side of the jumper wires and leave only the metal internal socket, connect them to the pogo pins and then use just one layer wrap of electrical isolation tape to prevent the terminals from touching. You can then put some hot glue on the whole lot to make it firmer, but I didn't in case I needed to redo any of the terminals. I additionally made the spacerplate slightly longer for support and found a stl file for a 3d printed clip by mjf55, which I very haphazardly adapted for my use in order to hold the pogo pin probe pressed down during programming. You can find a photo of the whole jury rigged adapter below.
As you can see, the whole thing is janky, but it worked. It held the pogo pin adapter in place, and after a bit of fiddling I managed to get a firm electrical connection, read the locked EC firmware (in three copies just to make sure there were no reading errors), unlocked it with RCUnlocker, flashed the unlocked firmware, reset the security settings to default and hey presto, the job was done.
I'm adding the openSCAD code for my modified spacerplate below, as well as the stl files for the spacerplate and clip. It's quite probable you will have to do some fiddling with the openSCAD code to make the holes the proper size when printing on your printer (I tried 1 to 1.25 mm in 0.05 mm increments and settled in the end on 1.2 mm). Or you can try the stl file directly and see if it fits your need.
Pogo_pin_Adapter_3d_print_files.zip
Some pointers:
-You have to be careful as you handle the pogo pin adapter when placing it into the clip and pressing on the test pads. You don't want to scratch or damage any electronics parts or the pogo pins. Go slow and use some foam underneath the clip just in case to prevent damage.
-You'll have to carefully align the pins to the test pads, use a magnifying glass or phone camera on zoom to check and adjust carefully if necessary. Patience is needed.
-I included just the spacer plate for the EC chip, but you can easily modify the openSCAD file to increase the distance between the two rows of pins to fit the BIOS chip test pads, you can find a portable version on openSCAD on their website, so you don't even need to install it.
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