diff --git a/FT240X-EEPROM.md b/FT240X-EEPROM.md
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+The FT240X EEPROM contains USB descriptor data, as well as a few magic bytes (see [USB protocol](USB-protocol)). It is 256 bytes (128 16-bit words) in size, and is read in units of 16 bits. Its contents are:
+
+```
+00000000  00 00 03 04 d0 7f 00 10  80 c8 08 00 00 00 a0 12  |................|
+00000010  b2 1e d0 1c 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+00000020  04 00 00 00 62 a7 7e 03  9f f5 f6 74 f4 01 00 00  |....b.~....t....|
+00000030  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+00000040  88 88 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+00000050  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+*
+00000080  56 36 a9 c9 01 00 6a 6c  ad 88 30 00 00 00 00 00  |V6....jl..0.....|
+00000090  00 00 00 01 44 4f 51 41  34 45 30 31 00 00 00 00  |....DOQA4E01....|
+000000a0  12 03 49 00 4b 00 41 00  4c 00 4f 00 47 00 49 00  |..I.K.A.L.O.G.I.|
+000000b0  43 00 1e 03 53 00 63 00  61 00 6e 00 61 00 51 00  |C...S.c.a.n.a.Q.|
+000000c0  75 00 61 00 64 00 20 00  53 00 51 00 35 00 30 00  |u.a.d. .S.Q.5.0.|
+000000d0  1c 03 31 00 30 00 30 00  33 00 30 00 35 00 30 00  |..1.0.0.3.0.5.0.|
+000000e0  30 00 30 00 35 00 34 00  38 00 32 00 00 00 00 00  |0.0.5.4.8.2.....|
+000000f0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 6a 3e  |..............j>|
+00000100  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
+*
+00000800
+```
+
+Parsed FTDI config output (using libftdi):
+
+```
+VID:     0x0403
+PID:     0x7fd0
+Release: 0x1000
+Bus Powered: 400 mA
+Manufacturer: IKALOGIC
+Product:      ScanaQuad SQ50
+Serial:       1003050005482
+Checksum      : 3e6a
+PNP: 1
+Channel A has Mode UART
+DBUS has 4 mA drive
+CBUS has 4 mA drive
+CBUS0 Function: TRISTATE
+CBUS1 Function: TRISTATE
+CBUS2 Function: TRISTATE
+CBUS3 Function: TRISTATE
+```
+
+The proprietary libftd2xx calls it an "X-series" device, while libftdi thinks it is an FT230X.
+
+"User data" starts at 0x24 (0x12 in 16-bit word units), which is where the 3-byte "magic unlock code" resides.
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