diff --git a/esp32_fw/include/serial.h b/esp32_fw/include/serial.h
index f5b600e9..d9476e6c 100644
--- a/esp32_fw/include/serial.h
+++ b/esp32_fw/include/serial.h
@@ -3,4 +3,5 @@
 void zbsTx(uint8_t* packetdata, uint8_t len);
 void zbsRxTask(void* parameter);
 
+void sendCancelPending(struct pendingData* pending);
 void sendDataAvail(struct pendingData* pending);
\ No newline at end of file
diff --git a/esp32_fw/src/newproto.cpp b/esp32_fw/src/newproto.cpp
index 1b1585ce..1f28f6a8 100644
--- a/esp32_fw/src/newproto.cpp
+++ b/esp32_fw/src/newproto.cpp
@@ -41,6 +41,12 @@ uint8_t* getDataForFile(File* file) {
     return ret;
 }
 
+void prepareCancelPending(uint64_t ver) {
+    struct pendingData pending = {0};
+    pending.availdatainfo.dataVer = ver;
+    sendCancelPending(&pending);
+}
+
 bool prepareDataAvail(String* filename, uint8_t dataType, uint8_t* dst) {
     *filename = "/" + *filename;
     if (!LittleFS.exists(*filename)) return false;
@@ -92,6 +98,7 @@ void processBlockRequest(struct espBlockRequest* br) {
 
     pendingdata* pd = pendingdata::findByVer(br->ver);
     if (pd == nullptr) {
+        prepareCancelPending(br->ver);
         Serial.printf("Couldn't find pendingdata info for ver %llu", br->ver);
         return;
     } else {
@@ -139,7 +146,7 @@ void processDataReq(struct espAvailDataReq* eadr) {
     uint8_t src[8];
     //    *((uint64_t*)src) = swap64(*((uint64_t*)adr->));
     sprintf(buffer, "<ADR %02X%02X%02X%02X%02X%02X%02X%02X\n\0", eadr->src[7], eadr->src[6], eadr->src[5], eadr->src[4], eadr->src[3], eadr->src[2], eadr->src[1], eadr->src[0]);
-    //sprintf(buffer, "<DATA REQ - version=%d, voltage=%d\n", adr->softVer, adr->batteryMv);
+    // sprintf(buffer, "<DATA REQ - version=%d, voltage=%d\n", adr->softVer, adr->batteryMv);
     wsString((String)buffer);
     Serial.print(buffer);
 }
diff --git a/esp32_fw/src/serial.cpp b/esp32_fw/src/serial.cpp
index c3df2624..bb3839ad 100644
--- a/esp32_fw/src/serial.cpp
+++ b/esp32_fw/src/serial.cpp
@@ -70,6 +70,18 @@ void sendDataAvail(struct pendingData* pending) {
     Serial1.write(0x00);
 }
 
+void sendCancelPending(struct pendingData* pending) {
+    addCRC(pending, sizeof(struct pendingData));
+    Serial1.print("CXD>");
+    for (uint8_t c = 0; c < sizeof(struct pendingData); c++) {
+        Serial1.write(((uint8_t*)pending)[c]);
+    }
+    Serial1.write(0x00);
+    Serial1.write(0x00);
+    Serial1.write(0x00);
+    Serial1.write(0x00);
+}
+
 uint8_t RXState = ZBS_RX_WAIT_HEADER;
 char cmdbuffer[4] = {0};
 uint8_t* packetp = nullptr;