DEV-793 Fix GSR on second-generation SR61 (HW gate + gen-2 feedback resistors)

Validated against a 33k/100k/470k fixed-resistor sweep on a real SR61-5 (DEV-793 datasets B4a-c, FW v2.00.013):
1) doesHwSupportGsr() now includes SR61 minor >= 5, mirroring the firmware's ShimBrd_isGsrSupportedForHwVersion (SR62 any / SR68 >= 5 / SR61 >= 5). Previously SR61-5/6 GSR recordings parsed to nothing.
2) SensorGSRVerisense now selects the second-generation DC-GSR feedback-resistor set (21/150/562/1740 kOhm) for SR61 as well as Pulse+ - with the Shimmer3 set (40.2/287/1000/3300 kOhm) the computed resistance was ~1.9x high, which also masqueraded as range-boundary clamping for the 33k and 470k recordings. Post-fix readings are within 0.8-1.5% of the fitted resistors across ranges 0-2.
3) GSR + LSM6DSV compatibility lists now include the Verisense IMU (SR61) hardware id; runtime gates (doesHwSupportGsr / isPayloadDesignV13orAbove) keep gen-1 SR61 units excluded.
Known sub-1% difference vs C#/TS: those use a 0.4986 V GSR reference for gen-2 where this driver uses 0.5 V (~0.3% in resistance) - below resistor tolerance, left unchanged for now.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: marknolan

ShimmerDriver/src/main/java/com/shimmerresearch/driver/Configuration.java

@@ -2721,14 +2721,17 @@ public static class CompatibilityInfoForMaps{
 			public static final List<ShimmerVerObject> listOfCompatibleVersionInfoVbatt = Arrays.asList(
 					svoVerisenseDevBrd, svoVerisenseImu, svoVerisensePpg0, svoVerisensePpg1, svoVerisenseGsrPlus, svoVerisensePulsePlus);
 
+			// SR61 (Verisense IMU) carries GSR from minor rev 5 (second-generation); the
+			// runtime minor-rev gating is in VerisenseDevice.doesHwSupportGsr() which
+			// mirrors the firmware's ShimBrd_isGsrSupportedForHwVersion.
 			public static final List<ShimmerVerObject> listOfCompatibleVersionInfoGsr = Arrays.asList(
-					svoVerisenseGsrPlus, svoVerisensePulsePlus);
+					svoVerisenseGsrPlus, svoVerisensePulsePlus, svoVerisenseImu);
 
-			// Second-generation IMU: LSM6DSV (accel/gyro) + LIS2MDL (mag), SR68-9/10.
-			// TODO refine to HW minor >= 9 once compat supports minor gating; matching all
-			// Pulse+ is acceptable for now as gen-1 Pulse+ carries no LSM6DSV.
+			// Second-generation IMU: LSM6DSV (accel/gyro) + LIS2MDL (mag), SR68-9/10 and
+			// SR61-5/6. TODO refine to HW minor gating once compat supports it; the
+			// runtime isPayloadDesignV13orAbove() gate protects gen-1 units meanwhile.
 			public static final List<ShimmerVerObject> listOfCompatibleVersionInfoLSM6DSV = Arrays.asList(
-					svoVerisensePulsePlus);
+					svoVerisensePulsePlus, svoVerisenseImu);
 		}
 
 	}

ShimmerDriver/src/main/java/com/shimmerresearch/verisense/VerisenseDevice.java

@@ -1295,7 +1295,11 @@ public boolean doesHwSupportMax30002() {
 	public boolean doesHwSupportGsr() {
 		int hwId = getHardwareVersion();
 		int hwRev = getExpansionBoardRev();
-		return (hwId==HW_ID.VERISENSE_GSR_PLUS || (hwId==HW_ID.VERISENSE_PULSE_PLUS && hwRev >=5));
+		// Mirrors the firmware's ShimBrd_isGsrSupportedForHwVersion (shimmer_boards.c):
+		// SR62 (any), SR68 minor >= 5, SR61 minor >= 5 (second-generation IMU carries GSR).
+		return (hwId==HW_ID.VERISENSE_GSR_PLUS
+				|| (hwId==HW_ID.VERISENSE_PULSE_PLUS && hwRev >=5)
+				|| (hwId==HW_ID.VERISENSE_IMU && hwRev >=5));
 	}
 
 	public CalibDetailsKinematic getCurrentCalibDetails(int sensorId) {

ShimmerDriver/src/main/java/com/shimmerresearch/verisense/sensors/SensorGSRVerisense.java

@@ -113,8 +113,15 @@ public static GSR_RANGE getForConfigValue(int configValue) {
 	//--------- Constructors for this class start --------------
 	public SensorGSRVerisense(ShimmerVerObject svo) {
 		super(svo);
-		
-		if (svo.getHardwareVersion() == HW_ID.VERISENSE_PULSE_PLUS) {
+
+		// The Pulse+ (SR68) and the second-generation Verisense IMU (SR61-5/6) share the
+		// same DC-based GSR front-end with its own feedback-resistor set; the GSR+ (SR62)
+		// uses the Shimmer3 values. An SR61 only gets this sensor class registered when
+		// VerisenseDevice.doesHwSupportGsr() has already confirmed HW minor >= 5, so no
+		// minor-revision check is needed here. Verified against a 33k/100k/470k resistor
+		// sweep on an SR61-5 (DEV-793 datasets B4a-c).
+		if (svo.getHardwareVersion() == HW_ID.VERISENSE_PULSE_PLUS
+				|| svo.getHardwareVersion() == HW_ID.VERISENSE_IMU) {
 			setCurrentGsrRefResistorsKohms(VERISENSE_PULSE_PLUS_GSR_REF_RESISTORS_KOHMS);
 			setCurrentGsrUncalLimitRange3(VERISENSE_PULSE_PLUS_GSR_UNCAL_LIMIT_RANGE3);
 		}