diff --git a/aws/cl_zcash/software/runtime/test_zcash.cpp b/aws/cl_zcash/software/runtime/test_zcash.cpp
index bff68b0..7b9091a 100644
--- a/aws/cl_zcash/software/runtime/test_zcash.cpp
+++ b/aws/cl_zcash/software/runtime/test_zcash.cpp
@@ -80,7 +80,7 @@ int main(int argc, char **argv) {
     uint32_t value = 0;
     unsigned int timeout = 0;
     unsigned int read_len = 0;
-    uint8_t reply[512];
+    uint8_t reply[640];
     // Process command line args
     {
         int i;
@@ -116,8 +116,8 @@ int main(int argc, char **argv) {
 
     // Store generator points in FPGA
     size_t g1_slot = 64;
-    size_t g2_slot = 68; 
-    
+    size_t g2_slot = 68;
+
     data.point_type = zcash_fpga::FP2_AF;
     memset(&data, 0x0, sizeof(zcash_fpga::bls12_381_data_t));
     string_to_hex("024aa2b2f08f0a91260805272dc51051c6e47ad4fa403b02b4510b647ae3d1770bac0326a805bbefd48056c8c121bdb8", (unsigned char *)data.dat);
@@ -151,7 +151,8 @@ int main(int argc, char **argv) {
     data.point_type = zcash_fpga::FP_AF;
     memset(&data, 0x0, sizeof(zcash_fpga::bls12_381_data_t));
     string_to_hex("08B3F481E3AAA0F1A09E30ED741D8AE4FCF5E095D5D00AF600DB18CB2C04B3EDD03CC744A2888AE40CAA232946C5E7E1", (unsigned char *)data.dat);
-    rc = zfpga.bls12_381_set_data_slot(g1_slot + 1, data);                                                                                                                                          fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
+    rc = zfpga.bls12_381_set_data_slot(g1_slot + 1, data);
+    fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
 
 
     data.point_type = zcash_fpga::SCALAR;
@@ -164,36 +165,51 @@ int main(int argc, char **argv) {
     inst.code = zcash_fpga::SEND_INTERRUPT;
     inst.a = 0;
     inst.b = 123;
-    rc = zfpga.bls12_381_set_inst_slot(1, inst);
+    rc = zfpga.bls12_381_set_inst_slot(5, inst);
     fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
 
     inst.code = zcash_fpga::SEND_INTERRUPT;
     inst.a = 1;
     inst.b = 456;
-    rc = zfpga.bls12_381_set_inst_slot(2, inst);
+    rc = zfpga.bls12_381_set_inst_slot(6, inst);
     fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
 
-    inst.code = zcash_fpga::POINT_MULT;
-    inst.a = 0;
-    inst.b = g1_slot;
+
+    // Multi pairing of e(G1, G2) . e(G1, G2)
+    inst.code = zcash_fpga::MILLER_LOOP;
+    inst.a = g1_slot;
+    inst.b = g2_slot;
     inst.c = 1;
     rc = zfpga.bls12_381_set_inst_slot(1, inst);
     fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
 
-    // Multi pairing
     inst.code = zcash_fpga::MILLER_LOOP;
-    inst.a = 1;
+    inst.a = g1_slot;
     inst.b = g2_slot;
+    inst.c = 13;
+    rc = zfpga.bls12_381_set_inst_slot(2, inst);
+    fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
+
+    inst.code = zcash_fpga::MUL_ELEMENT;
+    inst.a = 1;
+    inst.b = 12;
     inst.c = 1;
-    rc = zfpga.bls12_381_set_inst_slot(2, inst);                                                                                                                                                    fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
+    rc = zfpga.bls12_381_set_inst_slot(3, inst);
+    fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
 
+    inst.code = zcash_fpga::FINAL_EXP;
+    inst.a = 1;
+    inst.b = 1;
+    inst.c = 0;
+    rc = zfpga.bls12_381_set_inst_slot(4, inst);
+    fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
 
     // Start the test
     rc = zcash.bls12_381_set_curr_inst_slot(1);
     fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
 
     // Wait for interrupts
-    // Try read reply - should be our scalar value
+    // Try read reply - should be our scalar value - not using right now, could be used for point multiplication
 
     timeout = 0;
     read_len = 0;
@@ -211,11 +227,25 @@ int main(int argc, char **argv) {
     for (int i = read_len-1; i>=0; i--) printf("%x", reply[i]);
     printf("\n");
 
-    // Try read second reply - should be point value - 6 slots
-    memset(reply, 0, 512);
+    zcash_fpga::bls12_381_interrupt_rpl_t bls12_381_interrupt_rpl;
+
+    // Check it matches the expected values
+    bls12_381_interrupt_rpl = &(zcash_fpga::bls12_381_interrupt_rpl_t*)&reply;
+    if (bls12_381_interrupt_rpl.data_type != zcash_fpga::SCALAR) {
+      printf("ERROR: Interrupt data type was wrong, expected SCALAR, was [%d]\n", bls12_381_interrupt_rpl.data_type);
+    }
+    if (bls12_381_interrupt_rpl.index != 123) {
+      printf("ERROR: Interrupt index was wrong, expected 123, was [%d]\n", bls12_381_interrupt_rpl.index);
+    }
+    if (reply[sizeof(zcash_fpga::bls12_381_interrupt_rpl_t)] != 10) {
+      printf("ERROR: Interrupt data was wrong, expected 10, was [%d]\n", reply[sizeof(zcash_fpga::bls12_381_interrupt_rpl_t)]);
+    }
+
+    // Try read second reply - should be point value - 12 slots = 576 bytes
+    memset(reply, 0, 640);
     timeout = 0;
     read_len = 0;
-    while ((read_len = zfpga.read_stream(reply, 512)) == 0) {
+    while ((read_len = zfpga.read_stream(reply, 640)) == 0) {
       usleep(1);
       timeout++;
       if (timeout > 1000) {
@@ -228,6 +258,36 @@ int main(int argc, char **argv) {
     for (int i = read_len-1; i>=0; i--) printf("%x", reply[i]);
     printf("\n");
 
+    // Check it matches the expected values
+    bls12_381_interrupt_rpl = &(zcash_fpga::bls12_381_interrupt_rpl_t*)&reply;
+    if (bls12_381_interrupt_rpl.data_type != zcash_fpga::FE12) {
+      printf("ERROR: Interrupt data type was wrong, expected FE12, was [%d]\n", bls12_381_interrupt_rpl.data_type);
+    }
+    if (bls12_381_interrupt_rpl.index != 456) {
+      printf("ERROR: Interrupt index was wrong, expected 456, was [%d]\n", bls12_381_interrupt_rpl.index);
+    }
+
+    // Check it matches the value expected from our software model
+    uint8_t exp_res[640];
+    memset(exp_res, 0, 640);
+    string_to_hex("04fb0f149dd925d2c590a960936763e519c2b62e14c7759f96672cd852194325904197b0b19c6b528ab33566946af39b", (unsigned char *)&exp_res[0]);
+    string_to_hex("185ef728cf41a1b7b700b7e445f0b372bc29e370bc227d443c70ae9dbcf73fee8acedbd317a286a53266562d817269c0", (unsigned char *)&exp_res[48]);
+    string_to_hex("03a3734dbeb064bf4bc4a03f945a4921e49d04ab8d45fd753a28b8fa082616b4b17bbcb685e455ff3bf8f60c3bd32a0c", (unsigned char *)&exp_res[2*48]);
+    string_to_hex("1409cebef9ef393aa00f2ac64673675521e8fc8fddaf90976e607e62a740ac59c3dddf95a6de4fba15beb30c43d4e3f8", (unsigned char *)&exp_res[3*48]);
+    string_to_hex("1692a61ce5f4d7a093b2c46aa4bca6c4a66cf873d405ebc9c35d8aa639763720177b23beffaf522d5e41d3c5310ea333", (unsigned char *)&exp_res[4*48]);
+    string_to_hex("081abd33a78d31eb8d4c1bb3baab0529bb7baf1103d848b4cead1a8e0aa7a7b260fbe79c67dbe41ca4d65ba8a54a72b6", (unsigned char *)&exp_res[5*48]);
+    string_to_hex("0900410bb2751d0a6af0fe175dcf9d864ecaac463c6218745b543f9e06289922434ee446030923a3e4c4473b4e3b1914", (unsigned char *)&exp_res[6*48]);
+    string_to_hex("113286dee21c9c63a458898beb35914dc8daaac453441e7114b21af7b5f47d559879d477cf2a9cbd5b40c86becd07128", (unsigned char *)&exp_res[7*48]);
+    string_to_hex("06d8046c6b3424c4cd2d72ce98d279f2290a28a87e8664cb0040580d0c485f34df45267f8c215dcbcd862787ab555c7e", (unsigned char *)&exp_res[8*48]);
+    string_to_hex("0f6b8b52b2b5d0661cbf232820a257b8c5594309c01c2a45e64c6a7142301e4fb36e6e16b5a85bd2e437599d103c3ace", (unsigned char *)&exp_res[9*48]);
+    string_to_hex("017f1c95cf79b22b459599ea57e613e00cb75e35de1f837814a93b443c54241015ac9761f8fb20a44512ff5cfc04ac7f", (unsigned char *)&exp_res[10*48]);
+    string_to_hex("079ab7b345eb23c944c957a36a6b74c37537163d4cbf73bad9751de1dd9c68ef72cb21447e259880f72a871c3eda1b0c", (unsigned char *)&exp_res[11*48]);
+
+    if (memcmp((void*)reply[sizeof(zcash_fpga::bls12_381_interrupt_rpl_t)], (void*)exp_res, 576) != 0) {
+      printf("ERROR: Interrupt data was wrong (check data slot 1-13)!");
+    }
+
+
     // Read current instruction
     rc = zfpga.bls12_381_get_curr_inst_slot(slot_id);
     fail_on(rc, out, "ERROR: Unable to write to FPGA!\n");
@@ -235,14 +295,13 @@ int main(int argc, char **argv) {
     printf("Data slot is now %d\n", slot_id);
 
     // Print out data slots
-    for(int i = 0; i < 10; i++) {
+    for(int i = 0; i < 14; i++) {
       zfpga.bls12_381_get_data_slot(i, data);
       printf("slot %d, pt: %d, data:0x", i, data.point_type);
       for(int j = 47; j >= 0; j--) printf("%02x", data.dat[j]);
       printf("\n");
     }
 
-
     return rc;
 out:
     return 1;
diff --git a/aws/cl_zcash/software/runtime/zcash_fpga.hpp b/aws/cl_zcash/software/runtime/zcash_fpga.hpp
index 961355b..e1c7915 100644
--- a/aws/cl_zcash/software/runtime/zcash_fpga.hpp
+++ b/aws/cl_zcash/software/runtime/zcash_fpga.hpp
@@ -134,6 +134,13 @@ class zcash_fpga {
       fpga_state_t fpga_state;
     } fpga_status_rpl_t;
 
+    typedef struct __attribute__((__packed__)) {
+      header_t     hdr;
+      uint32_t     index;
+      point_type_t data_type;
+      uint8_t      padding[3];
+    } bls12_381_interrupt_rpl_t;
+
   private:
     static const uint16_t s_pci_vendor_id = 0x1D0F; /* Amazon PCI Vendor ID */
     static const uint16_t s_pci_device_id = 0xF000; /* PCI Device ID preassigned by Amazon for F1 applications */