diff --git a/cpp/jddisplay.cpp b/cpp/jddisplay.cpp
index 607e5a0..a4d4196 100644
--- a/cpp/jddisplay.cpp
+++ b/cpp/jddisplay.cpp
@@ -95,13 +95,21 @@ JDDisplay::JDDisplay(SPI *spi, Pin *cs, Pin *flow) : spi(spi), cs(cs), flow(flow
     EventModel::defaultEventBus->listen(flow->id, DEVICE_PIN_EVENT_ON_EDGE, this,
                                         &JDDisplay::onFlowHi, MESSAGE_BUS_LISTENER_IMMEDIATE);
     flow->eventOn(DEVICE_PIN_EVT_RISE);
-}
 
+    // set up polling for buttons
+    EventModel::defaultEventBus->listen(DEVICE_ID_COMPONENT, DEVICE_COMPONENT_EVT_SYSTEM_TICK, this, 
+                                        &JDDisplay::pollButtons, MESSAGE_BUS_LISTENER_IMMEDIATE);
+}
 
-/**
-* Deprecated; no longer neccessary. sendIndexedImage handles this.
-*/
-void JDDisplay::waitForSendDone() {}
+void JDDisplay::pollButtons(Event) {
+    if (stepWaiting) {
+        if (stepPrefix())
+            return;
+        // stepWaiting == false
+        flushSend();
+        sendDone(this);
+    }
+}
 
 void JDDisplay::sendDone(JDDisplay* jdd) {
     inProgressLock.notify();
@@ -215,12 +223,12 @@ void JDDisplay::handleIncoming(jd_packet_t *pkt) {
             buttonState = state;
         }
     } else {
-        // TODO remove later
         VLOG("JDA: unknown packet for %d (cmd=%x)", pkt->service_number, pkt->service_command);
     }
 }
 
-void JDDisplay::step() {
+
+bool JDDisplay::stepPrefix() {
     if (cs)
         cs->setDigitalValue(1);
 
@@ -228,10 +236,9 @@ void JDDisplay::step() {
     if (!flow->getDigitalValue()) {
         stepWaiting = true;
         target_enable_irq();
-        return;
-    } else {
-        stepWaiting = false;
+        return true;
     }
+    stepWaiting = false;
     target_enable_irq();
 
     memset(&sendFrame, 0, JD_SERIAL_FULL_HEADER_SIZE);
@@ -251,14 +258,19 @@ void JDDisplay::step() {
                 break;
         }
     }
-
     if (displayServiceNum == 0) {
         // poke the control service to enumerate
         queuePkt(JD_SERVICE_NUMBER_CTRL, JD_CMD_ADVERTISEMENT_DATA, 0);
         flushSend();
-        return;
+        return true;
     }
+    return false;
+}
 
+void JDDisplay::step() {
+    if (stepPrefix())
+        return;
+    // stepWaiting == false
     if (palette) {
         {
 #define PALETTE_SIZE (16 * 4)
diff --git a/cpp/jddisplay.h b/cpp/jddisplay.h
index d1ed7df..de63b87 100644
--- a/cpp/jddisplay.h
+++ b/cpp/jddisplay.h
@@ -44,12 +44,13 @@ class JDDisplay {
 
     void *queuePkt(uint32_t service_num, uint32_t service_cmd, uint32_t size);
     void flushSend();
+    bool stepPrefix();
     void step();
     void sendDone(JDDisplay* jdd);
     static void stepStatic(void *);
     void onFlowHi(Event);
     void handleIncoming(jd_packet_t *pkt);
-
+    void pollButtons(Event);
   public:
     uint8_t brightness;
     JDDisplay(SPI *spi, Pin *cs, Pin *flow);
@@ -59,8 +60,6 @@ class JDDisplay {
         addr.width = w;
         addr.height = h;
     }
-    void waitForSendDone();
-
     int sendIndexedImage(const uint8_t *src, unsigned width, unsigned height, uint32_t *palette);
 };
 
diff --git a/cpp/screen.cpp b/cpp/screen.cpp
index 7621106..f057cac 100644
--- a/cpp/screen.cpp
+++ b/cpp/screen.cpp
@@ -197,12 +197,6 @@ class WDisplay {
     else
       smart->setAddrWindow(offX, offY, width, displayHeight);
   }
-  void waitForSendDone() {
-    if (lcd)
-      lcd->waitForSendDone();
-    else
-      smart->waitForSendDone();
-  }
   int sendIndexedImage(const uint8_t *src, unsigned width, unsigned height,
                        uint32_t *palette) {
     if (lcd)
@@ -323,9 +317,6 @@ void updateScreen(Bitmap_ img) {
         img->height() * mult != display->displayHeight)
       target_panic(131); // PANIC_SCREEN_ERROR
 
-    // DMESG("wait for done");
-    display->waitForSendDone();
-
     auto palette = display->currPalette;
 
     if (display->newPalette) {
diff --git a/test.ts b/test.ts
index 56a105f..7b2cce5 100644
--- a/test.ts
+++ b/test.ts
@@ -1,27 +1,31 @@
-// namespace config {
-//    export const DISPLAY_CFG0 = 0x02030180 // allow execution without shield plugged in
-// }
+controller.left.onEvent(ControllerButtonEvent.Pressed, function () {
+    screen().fill(8)
+    screen().drawLine(0, 0, 160, 120, 1)
+    screen().drawLine(160, 0, 0, 120, 1)
+})
 
-// tests go here; this will not be compiled when this package is used as an extension.
+controller.right.onEvent(ControllerButtonEvent.Pressed, function () {
+    screen().fill(0)
+    screen().fillCircle(0, 0, 20, 3)
+    screen().fillCircle(160, 0, 20, 9)
+    screen().fillCircle(160, 120, 20, 7)
+    screen().fillCircle(0, 120, 20, 5)
+})
 
-const present = shieldhelpers.shieldPresent();
+let presses = 0;
+controller.A.onEvent(
+  ControllerButtonEvent.Pressed,
+  () => {
+      presses += 1
+})
 
-basic.showNumber(present ? 1 : 0)
+controller.B.onEvent(
+      ControllerButtonEvent.Pressed,
+  () => {
+      presses = 0
+    })
+
+input.onButtonPressed(Button.A, () => {
+    basic.showNumber(presses)
+})
 
-while (true) {
-    let x = 0
-    let my = theScreen.height -1
-    theScreen.fill(0)
-    theScreen.print((my+1).toString(), 60, 60)
-    while (x < 160) {
-        theScreen.setPixel(x, 0, 9)
-        theScreen.setPixel(x, 2, 10)
-        theScreen.setPixel(x, 4, 11)
-        theScreen.setPixel(x, my, 9)
-        theScreen.setPixel(x, my - 2, 10)
-        theScreen.setPixel(x, my - 4, 11)
-        x++
-        basic.pause(100)
-        // pause
-    }
-}