Updated Troubleshooting

doc/guide/troubleshooting.rst

@@ -14,3 +14,61 @@ Gowin device could not communicate since last bitstream flashed. (issue `#206 <h
 
 Gowin's FPGA may fails to be detected if **JTAGSEL_N** (pin 08 for *GW1N-4K*) is used as a GPIO.
 To recover you have to pull down this pin (before power up) to recover JTAG interface (*UG292 - JTAGSELL_N section*).
+
+JTAG init failed
+================
+
+Avoid using USB hubs like these:
+
+.. image:: media/usb_hub.jpg
+    :align: center
+
+and connect it directly to your PC USB port.
+
+
+Tang Primer 20k program slow and stucked (issue `#250 <https://github.com/trabucayre/openFPGALoader/issues/250>`_)
+==================================================================================================================
+
+Check your openFPGALoader version:
+
+.. code:: bash
+
+    openFPGALoader -V
+
+If it is older than release then v0.9.0, install the most recent version (from commit `f5b89bff68a5e2147404a895c075773884077438 <https://github.com/trabucayre/openFPGALoader/commit/fe259fb78d185b3113661d04cd7efa9ae0232425>`_ or later).
+
+Cannot flash Tang Nano 9k (issue `#251 <https://github.com/trabucayre/openFPGALoader/issues/251>`_)
+===================================================================================================
+
+This is a device issue, erase its Embedded Flash using Official GoWin Programmer (preferentially in Windows) and SRAM too, then you can use openFPGALoader again.
+
+Unable to open FTDI device: -4 (usb_open() failed) (issue `#245 <https://github.com/trabucayre/openFPGALoader/issues/245>`_)
+============================================================================================================================
+
+Edit your `/etc/udev/rules.d/99-ftdi.rules` file exchanging your programming device permissions.
+
+To identify what is your USB programming device, with your programmer UNPLUGGED run:
+
+.. code:: bash
+
+    watch lsusb
+
+You will see your USB devices connected to your computer, then plug in your programmer. You will notice there is a new device on the list.
+
+Let's suppose you found:
+
+.. code:: text
+
+    Bus 002 Device 004: ID 0403:6010 Future Technology Devices International, Ltd FT2232C/D/H Dual UART/FIFO IC
+                           \__/ \__/ \________________________________________________________________________/
+                            |     |                     |
+                            |     |                     \-----> Device Description Name
+                            |     \---------------------------> idProduct
+                            \---------------------------------> idVendor
+
+
+in this case, you will have to add/edit your udev rule file to:
+
+.. code:: bash
+
+    ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6010", MODE="0666"