diff --git a/docs/chapters/hardware_details.xml b/docs/chapters/hardware_details.xml
index f5f0e7d..17ab8cf 100644
--- a/docs/chapters/hardware_details.xml
+++ b/docs/chapters/hardware_details.xml
@@ -45,37 +45,54 @@
             </imageobject>
             <calloutlist>
                 <callout arearefs="usb" id="link_usb">
-                    <para>USB: USB mini-B connector. The main connector. The host software communicates (sniffing,...) through USB with the board. It can also be used to flash the micro-controller (using DFU).</para>
+                    <para>USB: USB mini-B connector. The main connector. The
+                    host software communicates (sniffing,...) through USB with
+                    the board. It can also be used to flash the micro-controller
+                    (using DFU).</para>
                 </callout>
                 <callout arearefs="serial" id="link_serial">
-                    <para>serial: 2.5 mm jack serial cable, as used by osmocomBB. port used to debug the device (printf goes there).</para>
+                    <para>serial: 2.5 mm jack serial cable, as used by osmocomBB
+                    port used to debug the device (printf goes there).</para>
                 </callout>
                 <callout arearefs="debug" id="link_debug">
-                    <para>debug (P3): same as serial, but using the FTDI serial cable.</para>
+                    <para>debug (P3): same as serial, but using the FTDI
+                    serial cable.</para>
                 </callout>
                 <callout arearefs="jtag" id="link_jtag">
-                    <para>jtag (P1): JTAG 20 pin connector to do hardware assisted debugging.</para>
+                    <para>jtag (P1): JTAG 20 pin connector to do hardware
+                    assisted debugging.</para>
                 </callout>
                 <callout arearefs="bt1" id="link_bt1">
-                    <para>BT1: battery connector (4.5-6V DC). normally the USB provides power, but the battery port can be used for autonomous use of SIMtrace. The sniffing can be saved in the flash (U1).</para>
+                    <para>BT1: battery connector (4.5-6V DC). normally the
+                    USB provides power, but the battery port can be used
+                    for autonomous use of SIMtrace. The sniffing can be saved
+                    in the flash (U1).</para>
                 </callout>
                 <callout arearefs="ffc" id="link_ffc">
-                    <para>FFC_SIM (P3): to connect the flat flexible cable with SIM end for the phone.</para>
+                    <para>FFC_SIM (P3): to connect the flat flexible cable with
+                    SIM end for the phone.</para>
                 </callout>
                 <callout arearefs="sim" id="link_sim">
-                    <para>SIM (P4): put your SIM in there (instead of in the phone)</para>
+                    <para>SIM (P4): put your SIM in there (instead of in the
+                    phone)</para>
                 </callout>
                 <callout arearefs="reset" id="link_reset">
-                    <para>reset (SW1): to reset the board (not erasing the firmware). If your are too lazy to unplug and re-plug the USB.</para>
+                    <para>reset (SW1): to reset the board (not erasing the
+                    firmware). If your are too lazy to unplug and re-plug
+                    the USB.</para>
                 </callout>
                 <callout arearefs="bootloader" id="link_bootloader">
-                    <para>bootloader (SW2): used to start the bootloader so to flash the device using DFU. press when plugging in the USB.</para>
+                    <para>bootloader (SW2): used to start the bootloader so
+                    to flash the device using DFU. press when plugging in
+                    the USB.</para>
                 </callout>
                 <callout arearefs="test" id="link_test">
-                    <para>test (JP1): short circuit using a jumper to flash using SAM-BA.</para>
+                    <para>test (JP1): short circuit using a jumper to flash
+                    using SAM-BA.</para>
                 </callout>
                 <callout arearefs="erase" id="link_erase">
-                    <para>erase (JP2): short circuit using a jumper to erase completely erase the firmware.</para>
+                    <para>erase (JP2): short circuit using a jumper to erase
+                    completely erase the firmware.</para>
                 </callout>
             </calloutlist>
             </imageobjectco>