4 files changed, 18 insertions, 2 deletions
diff --git a/Projects/AVRISP-MKII/AVRISP.c b/Projects/AVRISP-MKII/AVRISP.c
index e26d16c4c..81c1385c9 100644
--- a/Projects/AVRISP-MKII/AVRISP.c
+++ b/Projects/AVRISP-MKII/AVRISP.c
@@ -49,7 +49,6 @@ int main(void)
 	for (;;)
 	{
 		Process_AVRISP_Commands();
-		
 		V2Params_UpdateParamValues();
 		
 		USB_USBTask();
diff --git a/Projects/AVRISP-MKII/AVRISP.txt b/Projects/AVRISP-MKII/AVRISP.txt
index ab4472d9c..de08d5f37 100644
--- a/Projects/AVRISP-MKII/AVRISP.txt
+++ b/Projects/AVRISP-MKII/AVRISP.txt
@@ -262,6 +262,21 @@
  *        targets lacking an ADC.</i></td>  
  *   </tr>
  *   <tr>
+ *    <td>VTARGET_REF_VOLTS</td>
+ *    <td>Makefile CDEFS</td>
+ *    <td>Indicates the programmer AVR's AVCC reference voltage when measuring the target's supply voltage. Note that the supply
+ *        voltage should never exceed the reference voltage on the programmer AVR without some form of protection to prevent damage
+ *        to the ADC. <i>Ignored when compiled for targets lacking an ADC, or when NO_VTARGET_DETECT is defined.</i></td>  
+ *   </tr>
+ *   <tr>
+ *    <td>VTARGET_SCALE_FACTOR</td>
+ *    <td>Makefile CDEFS</td>
+ *    <td>Indicates the target's supply voltage scale factor when applied to the ADC. A simple resistive divider can be used on the
+ *        ADC pin for measuring the target's supply voltage, so that voltages above the programmer AVR's AVCC reference voltage can be
+ *        measured. This should be the reciprocal of the division performed - e.g. if the VTARGET voltage is halved, this should be set
+ *        to 2. <i>Ignored when compiled for targets lacking an ADC, or when NO_VTARGET_DETECT is defined.</i></td>  
+ *   </tr> 
+ *   <tr>
  *    <td>LIBUSB_DRIVER_COMPAT</td>
  *    <td>Makefile CDEFS</td>
  *    <td>Define to switch to a non-standard endpoint scheme, breaking compatibility with AVRStudio under Windows but making
diff --git a/Projects/AVRISP-MKII/Lib/V2ProtocolParams.c b/Projects/AVRISP-MKII/Lib/V2ProtocolParams.c
index de21f0ff2..bc3ed18e0 100644
--- a/Projects/AVRISP-MKII/Lib/V2ProtocolParams.c
+++ b/Projects/AVRISP-MKII/Lib/V2ProtocolParams.c
@@ -98,7 +98,7 @@ void V2Params_UpdateParamValues(void)
 {
 	#if (defined(ADC) && !defined(NO_VTARGET_DETECT))
 	/* Update VTARGET parameter with the latest ADC conversion of VTARGET on supported AVR models */
-	V2Params_SetParameterValue(PARAM_VTARGET, ((5 * 10 * ADC_GetResult()) / 1024));
+	V2Params_GetParamFromTable(PARAM_VTARGET)->ParamValue = (((uint16_t)(VTARGET_REF_VOLTS * 10 * VTARGET_SCALE_FACTOR) * ADC_GetResult()) / 1024);
 	#endif
 }
 
diff --git a/Projects/AVRISP-MKII/makefile b/Projects/AVRISP-MKII/makefile
index 9cba8730a..c6b64dfe1 100644
--- a/Projects/AVRISP-MKII/makefile
+++ b/Projects/AVRISP-MKII/makefile
@@ -197,6 +197,8 @@ CDEFS += -DAUX_LINE_MASK="(1 << 4)"
 CDEFS += -DVTARGET_ADC_CHANNEL=2
 CDEFS += -DENABLE_ISP_PROTOCOL
 CDEFS += -DENABLE_XPROG_PROTOCOL
+CDEFS += -DVTARGET_REF_VOLTS=5
+CDEFS += -DVTARGET_SCALE_FACTOR=1
 #CDEFS += -DNO_VTARGET_DETECT
 #CDEFS += -DLIBUSB_DRIVER_COMPAT