diff --git a/jtag/ChangeLog b/jtag/ChangeLog
index cbf9e1cb..97c7ddce 100644
--- a/jtag/ChangeLog
+++ b/jtag/ChangeLog
@@ -1,5 +1,7 @@
 2009-03-30  Arnim Laeuger  <arniml>
 
+  * UrJTAG.txt: multi-byte description
+
   * configure.ac: better description for flash-multi-byte
 
 2009-03-29  Arnim Laeuger <arniml>
diff --git a/jtag/doc/UrJTAG.txt b/jtag/doc/UrJTAG.txt
index 8c879fae..a9b4cfa9 100644
--- a/jtag/doc/UrJTAG.txt
+++ b/jtag/doc/UrJTAG.txt
@@ -290,6 +290,18 @@ be untested combinations of chip type, bus width, ...
  * AMD Am29LV64xD (Am29LV640D, Am29LV641D, Am29LV642D)
  * AMD Am29xx040B (Am29F040B, Am29LV040B)
 
+UrJTAG uses the multi-byte write mode if supported by the particular flash
+device. The flash code will automatically switch to this algorithm if the
+Device Geometry Definition reports that more than one memory location can be
+written in a single step (refer to CFI details shown by 'detectflash'). Since
+multiple locations are written in a burst-like manner with only one polling
+sequence afterwards, the overall flashing performance increases by factor of
+5-17.
+
+In case you encounter any issues with the multi-byte write mode, run configure
+with the '--disable-flash-multi-byte' option and re-compile to disable this
+algorithm.
+
 //------------------------------------------------------------------------
 
 === Compilation and installation ===