tcl/interface: add SPDX tag

[fw/openocd] / tcl / interface / ftdi / swd-resistor-hack.cfg

diff --git a/tcl/interface/ftdi/swd-resistor-hack.cfg b/tcl/interface/ftdi/swd-resistor-hack.cfg
index a6f3a26c5aaffb0125c9b461e80001e2934b67df..d9e71587192b8aa68057fc4e6f84c9422393315f 100644 (file)
--- a/tcl/interface/ftdi/swd-resistor-hack.cfg
+++ b/tcl/interface/ftdi/swd-resistor-hack.cfg
@@ -1,7 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
 #
 # Connect TDI to SWDIO via a suitable series resistor (220-470 Ohm or
 # so depending on the drive capability of the target and adapter);
 # connect TDO directly to SWDIO.
 #
+# You also need to have reliable GND connection between the target and
+# adapter. Vref of the adapter should be supplied with a voltage equal
+# to the target's (preferably connect it to Vcc). You can also
+# optionally connect nSRST. Leave everything else unconnected.
+#
+# FTDI                          Target
+# ----                          ------
+# 1  - Vref   ----------------- Vcc
+# 3  - nTRST  -
+# 4  - GND    ----------------- GND
+# 5  - TDI    ---/\470 Ohm/\--- SWDIO
+# 7  - TMS    -
+# 9  - TCK    ----------------- SWCLK
+# 11 - RTCK   -
+# 13 - TDO    ----------------- SWDIO
+# 15 - nSRST  - - - - - - - - - nRESET
+#
+
+transport select swd
 
-ftdi_layout_signal SWD_EN -data 0
+ftdi layout_signal SWD_EN -data 0