diff --git a/tcl/target/lpc2103.cfg b/tcl/target/lpc2103.cfg
index 3aa590bc1..f55777f56 100644
--- a/tcl/target/lpc2103.cfg
+++ b/tcl/target/lpc2103.cfg
@@ -2,8 +2,20 @@
 
 source [find target/lpc2xxx.cfg]
 
-proc init_targets {} {
-	# 32kB flash and 8kB SRAM, clocked with 12MHz crystal
+# parameters:
+# - core_freq_khz - frequency of core in kHz during flashing, usually equal to connected crystal or internal oscillator, e.g. 12000
+# - adapter_freq_khz - frequency of debug adapter in kHz, should be 8x slower than core_freq_khz, e.g. 1000
+
+proc setup_lpc2103 {core_freq_khz adapter_freq_khz} {
+	# 32kB flash and 8kB SRAM
 	# setup_lpc2xxx <chip_name> <cputapid> <flash_size> <flash_variant> <workarea_size> <core_freq_khz> <adapter_freq_khz>
-	setup_lpc2xxx lpc2103 0x4f1f0f0f 0x8000 lpc2000_v2 0x2000 12000 1500
+	setup_lpc2xxx lpc2103 0x4f1f0f0f 0x8000 lpc2000_v2 0x2000 $core_freq_khz $adapter_freq_khz
+}
+
+proc init_targets {} {
+	# default to core clocked with 12MHz crystal
+	echo "Warning - assuming default core clock 12MHz! Flashing may fail if actual core clock is different."
+	
+	# setup_lpc2103 <core_freq_khz> <adapter_freq_khz>
+	setup_lpc2103 12000 1500
 }
diff --git a/tcl/target/lpc2124.cfg b/tcl/target/lpc2124.cfg
index 94ac5be64..02517381a 100644
--- a/tcl/target/lpc2124.cfg
+++ b/tcl/target/lpc2124.cfg
@@ -2,8 +2,20 @@
 
 source [find target/lpc2xxx.cfg]
 
-proc init_targets {} {
-	# 256kB flash and 16kB SRAM, clocked with 12MHz crystal
+# parameters:
+# - core_freq_khz - frequency of core in kHz during flashing, usually equal to connected crystal or internal oscillator, e.g. 12000
+# - adapter_freq_khz - frequency of debug adapter in kHz, should be 8x slower than core_freq_khz, e.g. 1000
+
+proc setup_lpc2124 {core_freq_khz adapter_freq_khz} {
+	# 256kB flash and 16kB SRAM
 	# setup_lpc2xxx <chip_name> <cputapid> <flash_size> <flash_variant> <workarea_size> <core_freq_khz> <adapter_freq_khz>
-	setup_lpc2xxx lpc2124 0x4f1f0f0f 0x40000 lpc2000_v1 0x4000 12000 1500
+	setup_lpc2xxx lpc2124 0x4f1f0f0f 0x40000 lpc2000_v1 0x4000 $core_freq_khz $adapter_freq_khz
+}
+
+proc init_targets {} {
+	# default to core clocked with 12MHz crystal
+	echo "Warning - assuming default core clock 12MHz! Flashing may fail if actual core clock is different."
+	
+	# setup_lpc2124 <core_freq_khz> <adapter_freq_khz>
+	setup_lpc2124 12000 1500
 }
diff --git a/tcl/target/lpc2129.cfg b/tcl/target/lpc2129.cfg
index 10fcd0c17..2c33cde31 100644
--- a/tcl/target/lpc2129.cfg
+++ b/tcl/target/lpc2129.cfg
@@ -2,8 +2,20 @@
 
 source [find target/lpc2xxx.cfg]
 
-proc init_targets {} {
-	# 256kB flash and 16kB SRAM, clocked with 12MHz crystal
+# parameters:
+# - core_freq_khz - frequency of core in kHz during flashing, usually equal to connected crystal or internal oscillator, e.g. 12000
+# - adapter_freq_khz - frequency of debug adapter in kHz, should be 8x slower than core_freq_khz, e.g. 1000
+
+proc setup_lpc2129 {core_freq_khz adapter_freq_khz} {
+	# 256kB flash and 16kB SRAM
 	# setup_lpc2xxx <chip_name> <cputapid> <flash_size> <flash_variant> <workarea_size> <core_freq_khz> <adapter_freq_khz>
-	setup_lpc2xxx lpc2129 0xcf1f0f0f 0x40000 lpc2000_v1 0x4000 12000 1500
+	setup_lpc2xxx lpc2129 0xcf1f0f0f 0x40000 lpc2000_v1 0x4000 $core_freq_khz $adapter_freq_khz
+}
+
+proc init_targets {} {
+	# default to core clocked with 12MHz crystal
+	echo "Warning - assuming default core clock 12MHz! Flashing may fail if actual core clock is different."
+	
+	# setup_lpc2129 <core_freq_khz> <adapter_freq_khz>
+	setup_lpc2129 12000 1500
 }
diff --git a/tcl/target/lpc2148.cfg b/tcl/target/lpc2148.cfg
index 747dcd960..f3a2011a8 100644
--- a/tcl/target/lpc2148.cfg
+++ b/tcl/target/lpc2148.cfg
@@ -2,8 +2,20 @@
 
 source [find target/lpc2xxx.cfg]
 
-proc init_targets {} {
-	# 500kB flash and 32kB SRAM, clocked with 12MHz crystal
+# parameters:
+# - core_freq_khz - frequency of core in kHz during flashing, usually equal to connected crystal or internal oscillator, e.g. 12000
+# - adapter_freq_khz - frequency of debug adapter in kHz, should be 8x slower than core_freq_khz, e.g. 1000
+
+proc setup_lpc2148 {core_freq_khz adapter_freq_khz} {
+	# 500kB flash and 32kB SRAM
 	# setup_lpc2xxx <chip_name> <cputapid> <flash_size> <flash_variant> <workarea_size> <core_freq_khz> <adapter_freq_khz>
-	setup_lpc2xxx lpc2148 "0x3f0f0f0f 0x4f1f0f0f" 0x7d000 lpc2000_v2 0x8000 12000 1500
+	setup_lpc2xxx lpc2148 "0x3f0f0f0f 0x4f1f0f0f" 0x7d000 lpc2000_v2 0x8000 $core_freq_khz $adapter_freq_khz
+}
+
+proc init_targets {} {
+	# default to core clocked with 12MHz crystal
+	echo "Warning - assuming default core clock 12MHz! Flashing may fail if actual core clock is different."
+	
+	# setup_lpc2148 <core_freq_khz> <adapter_freq_khz>
+	setup_lpc2148 12000 1500
 }
diff --git a/tcl/target/lpc2294.cfg b/tcl/target/lpc2294.cfg
index b1042af0a..83d595deb 100644
--- a/tcl/target/lpc2294.cfg
+++ b/tcl/target/lpc2294.cfg
@@ -2,10 +2,22 @@
 
 source [find target/lpc2xxx.cfg]
 
-proc init_targets {} {
-	# 256kB flash and 16kB SRAM, clocked with 12MHz crystal
+# parameters:
+# - core_freq_khz - frequency of core in kHz during flashing, usually equal to connected crystal or internal oscillator, e.g. 12000
+# - adapter_freq_khz - frequency of debug adapter in kHz, should be 8x slower than core_freq_khz, e.g. 1000
+
+proc setup_lpc2294 {core_freq_khz adapter_freq_khz} {
+	# 256kB flash and 16kB SRAM
 	# setup_lpc2xxx <chip_name> <cputapid> <flash_size> <flash_variant> <workarea_size> <core_freq_khz> <adapter_freq_khz>
 	
 	# !! TAPID unknown !!
-	setup_lpc2xxx lpc2294 0xffffffff 0x40000 lpc2000_v1 0x4000 12000 1500
+	setup_lpc2xxx lpc2294 0xffffffff 0x40000 lpc2000_v1 0x4000 $core_freq_khz $adapter_freq_khz
+}
+
+proc init_targets {} {
+	# default to core clocked with 12MHz crystal
+	echo "Warning - assuming default core clock 12MHz! Flashing may fail if actual core clock is different."
+	
+	# setup_lpc2294 <core_freq_khz> <adapter_freq_khz>
+	setup_lpc2294 12000 1500
 }
diff --git a/tcl/target/lpc2378.cfg b/tcl/target/lpc2378.cfg
index 30c71aa55..0b66b8255 100644
--- a/tcl/target/lpc2378.cfg
+++ b/tcl/target/lpc2378.cfg
@@ -2,8 +2,20 @@
 
 source [find target/lpc2xxx.cfg]
 
-proc init_targets {} {
-	# 504kB flash and 32kB SRAM, clocked with 4MHz internal oscillator
+# parameters:
+# - core_freq_khz - frequency of core in kHz during flashing, usually equal to connected crystal or internal oscillator, e.g. 12000
+# - adapter_freq_khz - frequency of debug adapter in kHz, should be 8x slower than core_freq_khz, e.g. 1000
+
+proc setup_lpc2378 {core_freq_khz adapter_freq_khz} {
+	# 504kB flash and 32kB SRAM
 	# setup_lpc2xxx <chip_name> <cputapid> <flash_size> <flash_variant> <workarea_size> <core_freq_khz> <adapter_freq_khz>
-	setup_lpc2xxx lpc2378 0x4f1f0f0f 0x7e000 lpc2000_v2 0x8000 4000 500
+	setup_lpc2xxx lpc2378 0x4f1f0f0f 0x7e000 lpc2000_v2 0x8000 $core_freq_khz $adapter_freq_khz
+}
+
+proc init_targets {} {
+	# default to core clocked with 4MHz internal oscillator
+	echo "Warning - assuming default core clock 4MHz! Flashing may fail if actual core clock is different."
+	
+	# setup_lpc2378 <core_freq_khz> <adapter_freq_khz>
+	setup_lpc2378 4000 500
 }
diff --git a/tcl/target/lpc2478.cfg b/tcl/target/lpc2478.cfg
index 9c34b97e1..48e5bdf3f 100644
--- a/tcl/target/lpc2478.cfg
+++ b/tcl/target/lpc2478.cfg
@@ -2,8 +2,20 @@
 
 source [find target/lpc2xxx.cfg]
 
-proc init_targets {} {
-	# 504kB flash and 64kB SRAM, clocked with 4MHz internal oscillator
+# parameters:
+# - core_freq_khz - frequency of core in kHz during flashing, usually equal to connected crystal or internal oscillator, e.g. 12000
+# - adapter_freq_khz - frequency of debug adapter in kHz, should be 8x slower than core_freq_khz, e.g. 1000
+
+proc setup_lpc2478 {core_freq_khz adapter_freq_khz} {
+	# 504kB flash and 64kB SRAM
 	# setup_lpc2xxx <chip_name> <cputapid> <flash_size> <flash_variant> <workarea_size> <core_freq_khz> <adapter_freq_khz>
-	setup_lpc2xxx lpc2478 0x4f1f0f0f 0x7e000 lpc2000_v2 0x10000 4000 500
+	setup_lpc2xxx lpc2478 0x4f1f0f0f 0x7e000 lpc2000_v2 0x10000 $core_freq_khz $adapter_freq_khz
+}
+
+proc init_targets {} {
+	# default to core clocked with 4MHz internal oscillator
+	echo "Warning - assuming default core clock 4MHz! Flashing may fail if actual core clock is different."
+	
+	# setup_lpc2478 <core_freq_khz> <adapter_freq_khz>
+	setup_lpc2478 4000 500
 }