-//-----------------------------------------------------------------------------
-// Prepare tag messages
-//-----------------------------------------------------------------------------
-static void CodeIClassTagAnswer(const uint8_t *cmd, int len)
-{
-
-       /*
-        * SOF comprises 3 parts;
-        * * An unmodulated time of 56.64 us
-        * * 24 pulses of 423.75 KHz (fc/32)
-        * * A logic 1, which starts with an unmodulated time of 18.88us
-        *   followed by 8 pulses of 423.75kHz (fc/32)
-        *
-        *
-        * EOF comprises 3 parts:
-        * - A logic 0 (which starts with 8 pulses of fc/32 followed by an unmodulated
-        *   time of 18.88us.
-        * - 24 pulses of fc/32
-        * - An unmodulated time of 56.64 us
-        *
-        *
-        * A logic 0 starts with 8 pulses of fc/32
-        * followed by an unmodulated time of 256/fc (~18,88us).
-        *
-        * A logic 0 starts with unmodulated time of 256/fc (~18,88us) followed by
-        * 8 pulses of fc/32 (also 18.88us)
-        *
-        * The mode FPGA_HF_SIMULATOR_MODULATE_424K_8BIT which we use to simulate tag,
-        * works like this.
-        * - A 1-bit input to the FPGA becomes 8 pulses on 423.5kHz (fc/32) (18.88us).
-        * - A 0-bit inptu to the FPGA becomes an unmodulated time of 18.88us
-        *
-        * In this mode the SOF can be written as 00011101 = 0x1D
-        * The EOF can be written as 10111000 = 0xb8
-        * A logic 1 is 01
-        * A logic 0 is 10
-        *
-        * */
+               } else if (receivedCmd[0] == ICLASS_CMD_HALT && len == 1) {
+                       if (chip_state == SELECTED) {
+                               // Reader ends the session
+                               modulated_response = resp_sof;
+                               modulated_response_size = resp_sof_Len;
+                               chip_state = HALTED;
+                       }
+
+               } else if (simulationMode == ICLASS_SIM_MODE_FULL && receivedCmd[0] == ICLASS_CMD_READ4 && len == 4) {  // 0x06
+                       //Read 4 blocks
+                       if (chip_state == SELECTED) {
+                               uint8_t blockNo = receivedCmd[1];
+                               memcpy(data_generic_trace, emulator + current_page*page_size + blockNo*8, 8 * 4);
+                               AppendCrc(data_generic_trace, 8 * 4);
+                               trace_data = data_generic_trace;
+                               trace_data_size = 8 * 4 + 2;
+                               CodeIso15693AsTag(trace_data, trace_data_size);
+                               memcpy(data_response, ToSend, ToSendMax);
+                               modulated_response = data_response;
+                               modulated_response_size = ToSendMax;
+                       }
+
+               } else if (receivedCmd[0] == ICLASS_CMD_UPDATE && (len == 12 || len == 14)) {
+                       // We're expected to respond with the data+crc, exactly what's already in the receivedCmd
+                       // receivedCmd is now UPDATE 1b | ADDRESS 1b | DATA 8b | Signature 4b or CRC 2b
+                       if (chip_state == SELECTED) {
+                               uint8_t blockNo = receivedCmd[1];
+                               if (blockNo == 2) { // update e-purse
+                                       memcpy(card_challenge_data, receivedCmd+2, 8);
+                                       CodeIso15693AsTag(card_challenge_data, sizeof(card_challenge_data));
+                                       memcpy(resp_cc, ToSend, ToSendMax);
+                                       resp_cc_len = ToSendMax;
+                                       cipher_state_KD[current_page] = opt_doTagMAC_1(card_challenge_data, diversified_key_d);
+                                       cipher_state_KC[current_page] = opt_doTagMAC_1(card_challenge_data, diversified_key_c);
+                                       if (simulationMode == ICLASS_SIM_MODE_FULL) {
+                                               memcpy(emulator + current_page*page_size + 8*2, card_challenge_data, 8);
+                                       }
+                               } else if (blockNo == 3) { // update Kd
+                                       for (int i = 0; i < 8; i++) {
+                                               if (personalization_mode) {
+                                                       diversified_key_d[i] = receivedCmd[2 + i];
+                                               } else {
+                                                       diversified_key_d[i] ^= receivedCmd[2 + i];
+                                               }
+                                       }
+                                       cipher_state_KD[current_page] = opt_doTagMAC_1(card_challenge_data, diversified_key_d);
+                                       if (simulationMode == ICLASS_SIM_MODE_FULL) {
+                                               memcpy(emulator + current_page*page_size + 8*3, diversified_key_d, 8);
+                                       }
+                               } else if (blockNo == 4) { // update Kc
+                                       for (int i = 0; i < 8; i++) {
+                                               if (personalization_mode) {
+                                                       diversified_key_c[i] = receivedCmd[2 + i];
+                                               } else {
+                                                       diversified_key_c[i] ^= receivedCmd[2 + i];
+                                               }
+                                       }
+                                       cipher_state_KC[current_page] = opt_doTagMAC_1(card_challenge_data, diversified_key_c);
+                                       if (simulationMode == ICLASS_SIM_MODE_FULL) {
+                                               memcpy(emulator + current_page*page_size + 8*4, diversified_key_c, 8);
+                                       }
+                               } else if (simulationMode == ICLASS_SIM_MODE_FULL) { // update any other data block
+                                               memcpy(emulator + current_page*page_size + 8*blockNo, receivedCmd+2, 8);
+                               }
+                               memcpy(data_generic_trace, receivedCmd + 2, 8);
+                               AppendCrc(data_generic_trace, 8);
+                               trace_data = data_generic_trace;
+                               trace_data_size = 10;
+                               CodeIso15693AsTag(trace_data, trace_data_size);
+                               memcpy(data_response, ToSend, ToSendMax);
+                               modulated_response = data_response;
+                               modulated_response_size = ToSendMax;
+                       }
+
+               } else if (receivedCmd[0] == ICLASS_CMD_PAGESEL && len == 4) {
+                       // Pagesel
+                       // Chips with a single page will not answer to this command
+                       // Otherwise, we should answer 8bytes (conf block 1) + 2bytes CRC
+                       if (chip_state == SELECTED) {
+                               if (simulationMode == ICLASS_SIM_MODE_FULL && max_page > 0) {
+                                       current_page = receivedCmd[1];
+                                       memcpy(data_generic_trace, emulator + current_page*page_size + 8*1, 8);
+                                       memcpy(diversified_key_d, emulator + current_page*page_size + 8*3, 8);
+                                       memcpy(diversified_key_c, emulator + current_page*page_size + 8*4, 8);
+                                       cipher_state = &cipher_state_KD[current_page];
+                                       personalization_mode = data_generic_trace[7] & 0x80;
+                                       AppendCrc(data_generic_trace, 8);
+                                       trace_data = data_generic_trace;
+                                       trace_data_size = 10;
+                                       CodeIso15693AsTag(trace_data, trace_data_size);
+                                       memcpy(data_response, ToSend, ToSendMax);
+                                       modulated_response = data_response;
+                                       modulated_response_size = ToSendMax;
+                               }
+                       }