multi-byte description

git-svn-id: https://urjtag.svn.sourceforge.net/svnroot/urjtag/trunk@1473 b68d4a1b-bc3d-0410-92ed-d4ac073336b7

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>

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 ===