diff --git a/Hardware-info.md b/Hardware-info.md
index 66a01f3..92e2cda 100644
--- a/Hardware-info.md
+++ b/Hardware-info.md
@@ -30,4 +30,32 @@ Top side of the PCB:
 
 Bottom side of the PCB:
 
-![](https://cloud.lain.faith/apps/files_sharing/publicpreview/keFQb8DaK8m66QP?fileId=21070&file=/sq502.jpeg&x=1920&y=1080&a=true)
\ No newline at end of file
+![](https://cloud.lain.faith/apps/files_sharing/publicpreview/keFQb8DaK8m66QP?fileId=21070&file=/sq502.jpeg&x=1920&y=1080&a=true)
+
+### JTAG connector
+
+The board has an 8-pin 2mm(?) JTAG connector on the bottom side, under the USB connector. (Connection hasn't been tested with a JTAG probe yet, though. The pins have been checked with a continuity tester that it goes to the Spartan-3AN JTAG pins.) The pinout is as follows:
+
+```
+      _________
+     |top side |
+      \ w/ usb/
+       |_____|
+======================
+    _______________
+   | 1 2 3 4 5 6 7 |
+   | ' ' ' ' ' ' ' |
+   
+bottom side, jtag conn
+```
+
+1. unknown/not connected
+2. unknown/not connected
+3. TMS
+4. TDO
+5. TDI
+6. TCK
+7. GND
+8. VCC
+
+Perhaps the two 'nc' pins go to a different device.
\ No newline at end of file