 // the card reader adapter.  We also set the reader switch pin to HIGH
 // so the reader thinks that the card was physically removed.
 //
-void removeCard()
+// Parameters:
+//     print_response - Print response to the serial port if TRUE.  We
+//                      call this function internally and only want to
+//                      print a response if the user explicitly sent a
+//                      command to remove the card.
+//
+void removeCard(boolean print_response)
 {
     digitalWrite(reader_switch_pin, HIGH);
     digitalWrite(mux_en_pin, LOW);
     debug_print(String("Removed card " + String(inserted_card)));
     inserted_card = 0;
-    
+
     // Blank the display
     updateDisplay(-1);
-    Serial.println(RESP_OK);
+
+    // Print our serial response if requested.
+    if (print_response) {
+        Serial.println(RESP_OK);
+    }
 }
 
 // updateDisplay()

        } else if (strcmp(command, CMD_CARD_8) == 0) {
            insertCard(8);
        } else if (strcmp(command, CMD_REMOVE_CARD) == 0) {
            removeCard();
        } else if (strcmp(command, CMD_STATUS) == 0) {
            printCardStatus();
        } else if (strcmp(command, CMD_HELP) == 0) {

void loop();
int getCommand();
int insertCard(int card);
void removeCard(boolean print_response);
int updateDisplay(int digit);
void printCardStatus();
byte getCardStatus(int card);
