diff --git a/configs/ez80f910200zco/README.txt b/configs/ez80f910200zco/README.txt
index 553056a5f9..4ffc02c26e 100644
--- a/configs/ez80f910200zco/README.txt
+++ b/configs/ez80f910200zco/README.txt
@@ -4,8 +4,15 @@ README.txt
 ZDS-II Compiler Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^
 
-4.11.0
-  This is the only version that this code has been built against.
+Different configurations have been build for this board using ZDS-11
+Versions 4.11.0 and 4.11.1.  You have to check the files */Make.defs
+to see how the build is configured:  Check the definitions of
+ZDSVERSION (if present) and ZDSINSTALLDIR.
+
+NOTE:  Different versions of the ZDS-II compiler may also require
+different versions of .linkcmd and .zdsproj files as well.
+
+Version 4.11.0
 
   Although it compiles without error, the 4.11.0 compiler generates
   bad code on one of the files, mm/mm_initialize.c.  Below is a simple work-
diff --git a/configs/ez80f910200zco/ostest/Make.defs b/configs/ez80f910200zco/ostest/Make.defs
index f829c40ac3..37940a3a82 100644
--- a/configs/ez80f910200zco/ostest/Make.defs
+++ b/configs/ez80f910200zco/ostest/Make.defs
@@ -37,7 +37,8 @@ include ${TOPDIR}/.config
 
 # These are the directories where the ZDS-II toolchain is installed
 
-ZDSINSTALLDIR		:= C:/Program\ Files/ZiLOG/ZDSII_eZ80Acclaim!_4.11.0
+ZDSVERSION		:= 4.11.1
+ZDSINSTALLDIR		:= C:/Program\ Files/ZiLOG/ZDSII_eZ80Acclaim!_$(ZDSVERSION)
 ZDSBINDIR		:= $(ZDSINSTALLDIR)/bin
 ZDSSTDINCDIR		:= $(ZDSINSTALLDIR)/include/std
 ZDSZILOGINCDIR		:= $(ZDSINSTALLDIR)/include/zilog
diff --git a/configs/ez80f910200zco/ostest/ostest.linkcmd b/configs/ez80f910200zco/ostest/ostest.linkcmd
index 89b90e75e1..82600ec548 100755
--- a/configs/ez80f910200zco/ostest/ostest.linkcmd
+++ b/configs/ez80f910200zco/ostest/ostest.linkcmd
@@ -83,10 +83,10 @@ DEFINE __FLASH_ADDR_U_INIT_PARAM = $00
 
 define _SYS_CLK_FREQ = 50000000
 
-define _OSC_FREQ = 5000000
-define _SYS_CLK_SRC = 1
-define _OSC_FREQ_MULT = 10
-define __PLL_CTL0_INIT_PARAM = $41
+define _OSC_FREQ = 50000000
+define _SYS_CLK_SRC = 0
+define _OSC_FREQ_MULT = 1
+define __PLL_CTL0_INIT_PARAM = $0
 
 /* arch/z80/src/Makefile.zdsii will append target, object and library paths below */
 
diff --git a/configs/ez80f910200zco/ostest/ostest.zdsproj b/configs/ez80f910200zco/ostest/ostest.zdsproj
index d558a2e5f8..157b434ebc 100755
--- a/configs/ez80f910200zco/ostest/ostest.zdsproj
+++ b/configs/ez80f910200zco/ostest/ostest.zdsproj
@@ -1,4 +1,4 @@
-<project type="Executable" project-type="Standard" configuration="Debug" created-by="c:4.11:07071801" modified-by="c:4.11:07071801">
+<project type="Executable" project-type="Standard" configuration="Debug" created-by="c:4.11:07071801" modified-by="c:4.11:08011102">
 <cpu>eZ80F91</cpu>
 
 <!-- file information -->
@@ -42,7 +42,7 @@
 </tool>
 <tool name="Debugger">
 <options>
-<option name="target" type="string" change-action="rebuild">eZ80F91ModDevKit_Flash</option>
+<option name="target" type="string" change-action="rebuild">eZ80DevPlatform_F91_Flash</option>
 <option name="debugtool" type="string" change-action="none">USBSmartCable</option>
 <option name="usepageerase" type="boolean" change-action="none">true</option>
 </options>
@@ -100,13 +100,13 @@
 <option name="xref" type="boolean" change-action="none">true</option>
 <option name="undefisfatal" type="boolean" change-action="none">true</option>
 <option name="warnisfatal" type="boolean" change-action="none">false</option>
-<option name="sort" type="string" change-action="none">NAME</option>
+<option name="sort" type="string" change-action="none">ADDRESS</option>
 <option name="padhex" type="boolean" change-action="build">false</option>
 <option name="fplib" type="string" change-action="build">Real</option>
 <option name="useadddirectives" type="boolean" change-action="build">false</option>
 <option name="linkconfig" type="string" change-action="build">Standard</option>
 <option name="flashinfo" type="string" change-action="build">000000-0001FF</option>
-<option name="ram" type="string" change-action="build">B7E000-B7FFFF</option>
+<option name="ram" type="string" change-action="build">B8000-BfFFFF</option>
 <option name="rom" type="string" change-action="build">000000-03FFFF</option>
 <option name="extio" type="string" change-action="build">000000-00FFFF</option>
 <option name="intio" type="string" change-action="build">000000-0000FF</option>
diff --git a/configs/ez80f910200zco/ostest/setenv.sh b/configs/ez80f910200zco/ostest/setenv.sh
index 8aa2cd7117..ca2206980b 100755
--- a/configs/ez80f910200zco/ostest/setenv.sh
+++ b/configs/ez80f910200zco/ostest/setenv.sh
@@ -44,7 +44,7 @@ fi
 # Instead, alias are provided for all of the ZDS-II command line tools.
 # Version 4.10.1 installed in the default location is assumed here.
 #
-ZDSBINDIR="C:/Program\ Files/ZiLOG/ZDSII_eZ80Acclaim!_4.10.1/bin"
+ZDSBINDIR="C:/Program\ Files/ZiLOG/ZDSII_eZ80Acclaim!_4.11.1/bin"
 alias ez8asm="${ZDSBINDIR}/ez8asm.exe"
 alias ez8cc="${ZDSBINDIR}/ez8cc.exe"
 alias ez8lib="${ZDSBINDIR}/ez8lib.exe"