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in-circuit read\write FlashcatUSB 2.1 doesn't work


New Member
Hello there!
Falling from mine tree.
I own a FlashcatUSB 2.1 updated to the latest and I'm having some issue getting it right.

I'm either getting a "Flash memory detected but not found in flash library" with the (FlashCatUSB) VCC to (25x16vsig) VCC or (EXTERNAL USB 3.3v) VCC to (25x16vsig) VCC.
I can get the 25x16vsig chip recognized only if I remove the VCC entirely and booting the board one time, removing the power cord and discharging the residual power.
Issue is: even if recognized all the DATA is FF(empty).
By changing the (FlashCatUSB) SIO3 from the (25x16vsig) HOLD/IO3 (manual diagram page 14/25) to the (25x16vsig) VCC I can read some data but most of it's garbage. I know because I have the content already on backup from an un-soldered chip.

I know the FlashCatUSB is fully capable to read and write the content from\to when the 25x16vsig is not in-circuit, since physically detaching the 25x16 from the motherboard work but how can I get the FlashCatUSB working trough a IC clip? shouldn't be possible? I bought it for it.

Anyway, if you can help me there:
How do I properly attach the FlashCatUSB 2.1 to an IC CLIP to the in-circuit 25x16 SOIC (SOP) 8PIN?
( https://www.blackcatusb.net/index.php?threads/problem-with-connecting-flashcat-usb.500/page-2 give the same result, doesn't work )

I'm using the following template/diagram out-of-circuit and it work while inside a DIP8 adapter.

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New Member
With the Build 540 12-06-18 (hex4.40) I can read without error the first 100byte on the chip by moving the FlashCatUSB power switch to +5v and having the FCAT SIO3 on the 25x16 VCC.
This doesn't happen with the latest version, but anyway expectation are full write/read without making a mess on the desk.


New Member
I tested pretty much every combo I could think about.
If you think you could get it working draw some line\color or number on the attached image and re-post it.
I let you know if it work or not.



I have also come across some boards (like the Ubiquiti Unifi Wireless Access Points) that will not allow me to read the SPI while soldered on, you may have one of these.

Note: version 2.1 is best to use external 3.3v source, do not connect VCC of the FCUSB, if you have v2.2 or above you can use either VCC from FCUSB or external 3.3v (whatever works best)


New Member
Thanks for the reply ricktendo.
The board was actually an Intel DX58SO revision 501.
But I'm having the same issue this time with an DX58SO2 and I'm not going to desolder.
Is the FLASHCAT 2.1 capable to read SPI chip while attached on the circuit? or it's for out-of-circuit SOP only?
Older software version (hex4.40) report "Flash memory detected but not found in flash library" when QUAD check box is selected, latest doesn't detect anything.
Will the 2.3 work correctly?

This doesn't work either.
| w25 pins | Logic Master pins | function |
|/CS(1) | /CS(10) |SPI chip select input|
|DO(2) | MISO(12) | Master input,salve output |
|/WP(3)| VCC | Write protect input |
|GND(4)| GND| GND|
|DI(5) | MOSI(11)|Master output,salve input |
|CLK(6) |SCK(13) | SPI clock input |
|/HOLD(7)|VCC|Hold input|
|VCC(8) | VCC| VCC |

IC clip is POMONA.


New Member
I'm not even able to detect this one while on-circuit.
The Dediprog SF100 work out of the box by following the devKit guide..
EG: ( interleave 10 sec ) Powering ON the target board and powering it OFF leaving the led board on (system is not on)
Does I'm encountering some issue with the FLASHCAT I got? ( external 3.3 VCC doesn't work either )
or 72,53 EURO with TAX is a joke ( like the 3 euro CH134A ) since I ordered oversea and thus I need to pay 30 to return?
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New Member
The IC CLIP ISP-TC-8 of the dediprog seems bridged with the PIN 8 to PIN 2 and PIN 7 to PIN 3.
Nonetheless this doesn't work either with the FLASHCAT by making the circuit on a open pomona clip, so, is there a way to get the FLASHCAT recognizing the W25Q16BV plus fully reading and writing without desoldering? I might missing something. Thanks.
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