diff --git a/slsDetectorServers/ctbDetectorServer/slsDetectorFunctionList.c b/slsDetectorServers/ctbDetectorServer/slsDetectorFunctionList.c
index d7f9e4f56..3c0d25d7c 100644
--- a/slsDetectorServers/ctbDetectorServer/slsDetectorFunctionList.c
+++ b/slsDetectorServers/ctbDetectorServer/slsDetectorFunctionList.c
@@ -15,6 +15,7 @@
 #include "loadPattern.h"
 
 #include <netinet/in.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h> // usleep
@@ -93,6 +94,7 @@ void basictests() {
     LOG(logINFOBLUE, ("********* Chip Test Board Virtual Server *********\n"));
 #else
     LOG(logINFOBLUE, ("************* Chip Test Board Server *************\n"));
+    enableBlackfinAMCExternalAccessExtension();
     initError = defineGPIOpins(initErrorMessage);
     if (initError == FAIL) {
         return;
@@ -438,6 +440,33 @@ uint32_t getDetectorIP() {
     return res;
 }
 
+void enableBlackfinAMCExternalAccessExtension() {
+    unsigned int value;
+    const char *file_path = "/sys/kernel/debug/blackfin/ebiu_amc/EBIU_AMBCTL1";
+
+    FILE *file = fopen(file_path, "r");
+    if (!file) {
+        LOG(logERROR, ("Failed to read EBIU_AMBCTL1\n"));
+        return;
+    }
+    fscanf(file, "%x", &value);
+    fclose(file);
+
+    // enable support for ARDY signal on interface to FPGA
+    // needed to properly translate avalon_mm_waitrequest in the CTB firmware
+    // https://www.analog.com/media/en/dsp-documentation/processor-manuals/bf537_hwr_Rev3.2.pdf
+    // page 274
+    value |= 0x3;
+
+    file = fopen(file_path, "w");
+    if (!file) {
+        LOG(logERROR, ("Failed to enable blackfin AMC access extension\n"));
+        return;
+    }
+    fprintf(file, "0x%x", value);
+    fclose(file);
+}
+
 /* initialization */
 
 void initControlServer() {
diff --git a/slsDetectorServers/slsDetectorServer/include/slsDetectorFunctionList.h b/slsDetectorServers/slsDetectorServer/include/slsDetectorFunctionList.h
index f572252bd..80bad5898 100644
--- a/slsDetectorServers/slsDetectorServer/include/slsDetectorFunctionList.h
+++ b/slsDetectorServers/slsDetectorServer/include/slsDetectorFunctionList.h
@@ -135,6 +135,7 @@ void setupDetector();
 #if defined(CHIPTESTBOARDD)
 int updateDatabytesandAllocateRAM();
 void updateDataBytes();
+void enableBlackfinAMCExternalAccessExtension();
 #endif
 
 #if !defined(CHIPTESTBOARDD) && !defined(XILINX_CHIPTESTBOARDD)