diff --git a/artiq/firmware/libboard_artiq/grabber.rs b/artiq/firmware/libboard_artiq/grabber.rs
new file mode 100644
index 000000000..a70cb0e28
--- /dev/null
+++ b/artiq/firmware/libboard_artiq/grabber.rs
@@ -0,0 +1,93 @@
+use board_misoc::csr;
+
+static mut GRABBER_UP: &'static mut [bool] = &mut [false; csr::GRABBER_LEN];
+
+fn get_pll_reset(g: usize) -> bool {
+    unsafe { (csr::GRABBER[g].pll_reset_read)() != 0 }
+}
+
+fn set_pll_reset(g: usize, reset: bool) {
+    let val = if reset { 1 } else { 0 };
+    unsafe { (csr::GRABBER[g].pll_reset_write)(val) }   
+}
+
+fn pll_locked(g: usize) -> bool {
+    unsafe { (csr::GRABBER[g].pll_locked_read)() != 0 }
+}
+
+fn clock_pattern_ok(g: usize) -> bool {
+    unsafe { (csr::GRABBER[g].clk_sampled_read)() == 0b1100011 }
+}
+
+fn clock_pattern_ok_filter(g: usize) -> bool {
+    for _ in 0..128 {
+        if !clock_pattern_ok(g) {
+            return false;
+        }
+    }
+    true
+}
+
+fn phase_shift(g: usize, direction: u8) {
+    unsafe {
+        (csr::GRABBER[g].phase_shift_write)(direction);
+        while (csr::GRABBER[g].phase_shift_done_read)() == 0 {}
+    }
+}
+
+fn clock_align(g: usize) -> bool {
+    while clock_pattern_ok_filter(g) {
+        phase_shift(g, 1);
+    }
+    phase_shift(g, 1);
+
+    let mut count = 0;
+    while !clock_pattern_ok_filter(g) {
+        phase_shift(g, 1);
+        count += 1;
+        if count > 1024 {
+            return false;
+        }
+    }
+
+    let mut window = 1;
+    phase_shift(g, 1);
+    while clock_pattern_ok_filter(g) {
+        phase_shift(g, 1);
+        window += 1;
+    }
+
+    for _ in 0..window/2 {
+        phase_shift(g, 0);
+    }
+
+    true
+}
+
+pub fn tick() {
+    for g in 0..csr::GRABBER.len() {
+        if unsafe { GRABBER_UP[g] } {
+            if !clock_pattern_ok(g) || !pll_locked(g) {
+                set_pll_reset(g, true);
+                unsafe { GRABBER_UP[g] = false; }
+                info!("grabber{} is down", g);
+            }
+        } else {
+            if get_pll_reset(g) {
+                set_pll_reset(g, false);
+            } else {
+                if pll_locked(g) {
+                    info!("grabber{} PLL is locked", g);
+                    if clock_align(g) {
+                        info!("grabber{} is up", g);
+                        unsafe { GRABBER_UP[g] = true; }
+                    } else {
+                        set_pll_reset(g, true);
+                    }
+                } else {
+                    set_pll_reset(g, true);
+                }
+            }
+        }
+    }
+}
diff --git a/artiq/firmware/libboard_artiq/lib.rs b/artiq/firmware/libboard_artiq/lib.rs
index af8c1336a..3402a1d2f 100644
--- a/artiq/firmware/libboard_artiq/lib.rs
+++ b/artiq/firmware/libboard_artiq/lib.rs
@@ -40,6 +40,8 @@ mod ad9154_reg;
 pub mod ad9154;
 #[cfg(has_allaki_atts)]
 pub mod hmc542;
+#[cfg(has_grabber)]
+pub mod grabber;
 
 #[cfg(has_drtio)]
 pub mod drtioaux;
diff --git a/artiq/firmware/runtime/main.rs b/artiq/firmware/runtime/main.rs
index f0bef4108..eaaa1721d 100644
--- a/artiq/firmware/runtime/main.rs
+++ b/artiq/firmware/runtime/main.rs
@@ -168,6 +168,14 @@ fn setup_si5324_as_synthesizer()
         board_artiq::si5324::Input::Ckin2).expect("cannot initialize Si5324");
 }
 
+#[cfg(has_grabber)]
+fn grabber_thread(io: sched::Io) {
+    loop {
+        board_artiq::grabber::tick();
+        io.sleep(200).unwrap();
+    }
+}
+
 #[cfg(has_ethmac)]
 fn startup_ethernet() {
     let hardware_addr;
@@ -237,6 +245,8 @@ fn startup_ethernet() {
     io.spawn(4096, moninj::thread);
     #[cfg(has_rtio_analyzer)]
     io.spawn(4096, analyzer::thread);
+    #[cfg(has_grabber)]
+    io.spawn(4096, grabber_thread);
 
     let mut net_stats = ethmac::EthernetStatistics::new();
     loop {
diff --git a/conda/artiq-dev/meta.yaml b/conda/artiq-dev/meta.yaml
index ec43ce29c..8ecff1168 100644
--- a/conda/artiq-dev/meta.yaml
+++ b/conda/artiq-dev/meta.yaml
@@ -15,7 +15,7 @@ requirements:
     - python >=3.5.3,<3.6
     - setuptools 33.1.1
     - migen 0.7 py35_35+git9bc084a
-    - misoc 0.11 py35_14+gitc60ccfb2
+    - misoc 0.11 py35_15+git7f63aff5
     - jesd204b 0.5
     - microscope
     - binutils-or1k-linux >=2.27