diff --git a/src/gateware/cxp.py b/src/gateware/cxp.py
new file mode 100644
index 0000000..d400431
--- /dev/null
+++ b/src/gateware/cxp.py
@@ -0,0 +1,602 @@
+from migen import *
+from migen.genlib.cdc import MultiReg, PulseSynchronizer
+from misoc.interconnect.csr import *
+from misoc.interconnect.stream import StrideConverter
+
+from artiq.gateware.rtio import rtlink
+
+from cxp_downconn import CXP_RXPHYs
+from cxp_upconn import CXP_TXPHYs
+from cxp_pipeline import (
+    Command_Packet_Reader,
+    Command_Test_Packet_Writer,
+    Duplicated_Char_Decoder,
+    Heartbeat_Packet_Reader,
+    Idle_Word_Inserter,
+    Packet_Arbiter,
+    Packet_Wrapper,
+    Test_Sequence_Checker,
+    Trigger_ACK_Inserter,
+    Trigger_ACK_Reader,
+    Trigger_Inserter,
+    Trigger_Reader,
+)
+from cxp_frame_pipeline import *
+
+import cxp_router
+
+from types import SimpleNamespace
+
+class CXP_PHYS(Module, AutoCSR):
+    def __init__(self, refclk, upconn_pads, downconn_pads, sys_clk_freq, master=0):
+        assert len(upconn_pads) == len(downconn_pads)
+
+        self.submodules.tx = CXP_TXPHYs(upconn_pads, sys_clk_freq)
+        self.submodules.rx = CXP_RXPHYs(refclk, downconn_pads, sys_clk_freq, master)
+
+        self.phys = []
+        for tx, rx in zip(self.tx.phys, self.rx.phys):
+            phy = SimpleNamespace()
+            phy.tx, phy.rx = tx, rx
+            self.phys.append(phy)
+        
+
+class CXP_Core(Module, AutoCSR):
+    def __init__(self, phy, command_buffer_depth=32, nrxslot=4):
+        # control buffer is only 32 words (128 bytes) for compatibility with version1.x compliant Devices
+        # Section 12.1.6 (CXP-001-2021)
+        self.buffer_depth, self.nslots = command_buffer_depth, nrxslot
+        
+        self.submodules.tx = TX_Pipeline(phy.tx, command_buffer_depth, False)
+        self.submodules.rx = RX_Pipeline(phy.rx, command_buffer_depth, nrxslot, False)
+
+    def get_tx_port(self):
+        return self.tx.writer.mem.get_port(write_capable=True)
+
+    def get_rx_port(self):
+        return self.rx.command_reader.mem.get_port(write_capable=False)
+
+    def get_mem_size(self):
+        return word_width * self.buffer_depth * self.nslots // 8
+
+class RX_Pipeline(Module, AutoCSR):
+    def __init__(self, phy, command_buffer_depth, nslot, with_trigger):
+        self.ready = CSRStatus()
+
+        self.trigger_ack = CSR()
+
+        self.pending_packet = CSR()
+        self.read_ptr = CSRStatus(log2_int(nslot))
+        self.reader_buffer_err = CSR()
+
+        self.reader_decode_err = CSR()
+        self.test_error_counter = CSRStatus(16)
+        self.test_packet_counter = CSRStatus(16)
+        self.test_counts_reset = CSR()
+
+        self.heartbeat = CSR()
+        self.host_id = CSRStatus(32)
+        self.device_time = CSRStatus(64)
+
+        # for multilane router
+        self.active = Signal()
+
+        if with_trigger:
+            self.trig = Signal()
+            self.trig_delay = Signal(char_width)
+            self.trig_linktrigger_n = Signal(char_width)
+        
+        # # #
+
+        gtx = phy.gtx
+        self.sync += [
+            self.ready.status.eq(gtx.rx_ready),
+            self.active.eq(gtx.rx_ready),
+        ]
+
+        # Host rx pipeline 
+        #
+        #        32             32+8(dchar)
+        # PHY ───/───> dchar   ─────/─────> trigger  ─────> trigger ack ─────>  packet parser  ─────> EOP Marker ─────> stream data packet
+        #              decoder              reader          reader               │  │  │                                with CRC
+        #                                 (optional)                             │  │  └──────> test sequence checker
+        #                                                                        │  │
+        #                                                                        │  └─────────> heartbeat packet reader
+        #                                                                        │   
+        #                                                                        └────────────> command packet reader
+        #  
+        cdr = ClockDomainsRenamer("cxp_gtx_rx")
+
+        # decode all incoming data as duplicate char and inject the result into the bus for downstream modules
+        self.submodules.dchar_decoder = dchar_decoder = cdr(Duplicated_Char_Decoder())
+
+        # Priority level 0 packet - Trigger packet
+        if with_trigger:
+            self.submodules.trig_reader = trig_reader = cdr(Trigger_Reader())
+            self.sync.cxp_gtx_rx += [
+                self.trig.eq(trig_reader.trig),
+                self.trig_delay.eq(trig_reader.delay),
+                self.trig_linktrigger_n.eq(trig_reader.linktrigger_n),
+            ]
+
+        # Priority level 1 packet - Trigger ack packet
+        self.submodules.trig_ack_reader= trig_ack_reader = cdr(Trigger_ACK_Reader())
+        
+        self.submodules.trig_ack_ps = trig_ack_ps = PulseSynchronizer("cxp_gtx_rx", "sys")
+        self.sync.cxp_gtx_rx += trig_ack_ps.i.eq(trig_ack_reader.ack)
+        self.sync += [
+            If(trig_ack_ps.o,
+                self.trigger_ack.w.eq(1),
+            ).Elif(self.trigger_ack.re,
+                self.trigger_ack.w.eq(0),
+            ),
+        ]
+
+        # Priority level 2 packet - stream, test, heartbeat and command packets
+        self.submodules.arbiter = arbiter = cdr(Packet_Arbiter())
+
+        self.submodules.decode_err_ps = decode_err_ps = PulseSynchronizer("cxp_gtx_rx", "sys")
+        self.sync.cxp_gtx_rx += decode_err_ps.i.eq(arbiter.decode_err)
+        self.sync += [
+            If(decode_err_ps.o,
+                self.reader_decode_err.w.eq(1),
+            ).Elif(self.reader_decode_err.re,
+                self.reader_decode_err.w.eq(0),
+            ),
+        ]
+
+        if with_trigger:
+            rx_pipeline = [phy, dchar_decoder, trig_reader, trig_ack_reader, arbiter]
+        else:
+            rx_pipeline = [phy, dchar_decoder, trig_ack_reader, arbiter]
+        for s, d in zip(rx_pipeline, rx_pipeline[1:]):
+            self.comb += s.source.connect(d.sink)
+
+        # Stream packet
+        # Drop the K29.7 and mark the EOP for downstream
+        self.submodules.eop_marker = eop_marker = cdr(EOP_Marker())
+        self.comb += arbiter.source_stream.connect(eop_marker.sink)
+
+        # set pipeline source to output stream packet 
+        self.source = eop_marker.source
+
+
+        # Test packet 
+        self.submodules.test_seq_checker = test_seq_checker = cdr(Test_Sequence_Checker())
+        self.comb += arbiter.source_test.connect(test_seq_checker.sink)
+        
+        self.submodules.test_reset_ps = test_reset_ps = PulseSynchronizer("sys", "cxp_gtx_rx")
+        self.comb += test_reset_ps.i.eq(self.test_counts_reset.re),
+
+        test_err_cnt_rx = Signal.like(self.test_error_counter.status)
+        test_pak_cnt_rx = Signal.like(self.test_packet_counter.status)
+        test_err_r, test_pak_r = Signal(), Signal()
+        self.sync.cxp_gtx_rx += [ 
+            test_err_r.eq(test_seq_checker.error),
+            test_pak_r.eq(arbiter.recv_test_pak),
+
+            If(test_reset_ps.o,
+                test_err_cnt_rx.eq(test_err_cnt_rx.reset),
+            ).Elif(test_err_r,
+                test_err_cnt_rx.eq(test_err_cnt_rx + 1),
+            ),
+            If(test_reset_ps.o,
+                test_pak_cnt_rx.eq(test_pak_cnt_rx.reset),
+            ).Elif(test_pak_r,
+                test_pak_cnt_rx.eq(test_pak_cnt_rx + 1),
+            ),
+        ]
+        self.specials += [
+            MultiReg(test_err_cnt_rx, self.test_error_counter.status),
+            MultiReg(test_pak_cnt_rx, self.test_packet_counter.status),
+        ]
+
+        # Command packet
+        self.submodules.command_reader = command_reader = cdr(Command_Packet_Reader(command_buffer_depth, nslot))
+        self.comb += arbiter.source_command.connect(command_reader.sink)
+
+        # nslot buffers control interface
+        write_ptr_sys = Signal.like(command_reader.write_ptr)
+        
+        self.specials += [
+            MultiReg(self.read_ptr.status, command_reader.read_ptr, odomain="cxp_gtx_rx"),
+            MultiReg(command_reader.write_ptr, write_ptr_sys)
+        ]
+        self.sync += [
+            self.pending_packet.w.eq(self.read_ptr.status != write_ptr_sys),
+            If(~gtx.rx_ready,
+                self.read_ptr.status.eq(0),
+            ).Elif(self.pending_packet.re & self.pending_packet.w, 
+                self.read_ptr.status.eq(self.read_ptr.status + 1),
+            )
+        ]
+
+        self.submodules.buffer_err_ps = buffer_err_ps = PulseSynchronizer("cxp_gtx_rx", "sys")
+        self.sync.cxp_gtx_rx += buffer_err_ps.i.eq(command_reader.buffer_err),
+        self.sync += [
+            If(buffer_err_ps.o,
+                self.reader_buffer_err.w.eq(1),
+            ).Elif(self.reader_buffer_err.re,
+                self.reader_buffer_err.w.eq(0),
+            ),
+        ]
+
+        # Heartbeat packet
+        self.submodules.heartbeat_reader = heartbeat_reader = cdr(Heartbeat_Packet_Reader())
+        self.comb += arbiter.source_heartbeat.connect(heartbeat_reader.sink)
+
+        self.specials += [
+            MultiReg(heartbeat_reader.host_id, self.host_id.status),
+            MultiReg(heartbeat_reader.heartbeat, self.device_time.status),
+        ]
+        
+        self.submodules.heartbeat_ps = heartbeat_ps = PulseSynchronizer("cxp_gtx_rx", "sys")
+        self.sync.cxp_gtx_rx += heartbeat_ps.i.eq(arbiter.recv_heartbeat)
+        self.sync += [
+            If(heartbeat_ps.o,
+                self.heartbeat.w.eq(1),
+            ).Elif(self.heartbeat.re,
+                self.heartbeat.w.eq(0),
+            ),
+        ]
+        
+
+
+
+        
+class TX_Pipeline(Module, AutoCSR):
+    def __init__(self, phy, command_buffer_depth, with_trigger_ack):
+        self.trig_stb = Signal()
+        self.trig_delay = Signal(char_width)
+        self.trig_linktrigger_mode = Signal()
+
+        if with_trigger_ack:
+            self.trig_ack_stb = Signal()
+        
+        # # #
+        
+        # Host tx pipeline
+        #
+        #                 32                                                  32            8
+        # command/test ───/───> packet ─────> idle word ─────> trigger ack ───/───> conv ───/───> trigger ─────> PHY
+        # packet writer         wrapper       inserter         inserter                           inserter
+        #                                                      (optional)
+        #
+        # Equivalent transmission priority:
+        # trigger > tigger ack > idle word > command/test packet
+        #
+        # The pipeline is splited into 32 and 8 bits section to handle the word and char boundary priority insertion requirement:
+        # Insertion @ char boundary: trigger packets
+        # Insertion @ word boundary: idle packets and trigger ack packet
+        # - Section 9.2.4 (CXP-001-2021)
+        # 
+        # The idle inserter is placed between the trigger ack inserter and command/test packet writer to maintain the trigger performance,
+        # as idle word should not be inserted into trigger and trigger ack packet - Section 9.2.5.1 (CXP-001-2021) 
+        # 
+        
+
+        # Priority level 0 packet - Trigger packet
+        self.submodules.trig = trig = Trigger_Inserter()
+        self.comb += [
+            trig.stb.eq(self.trig_stb),
+            trig.delay.eq(self.trig_delay),
+            trig.linktrig_mode.eq(self.trig_linktrigger_mode)
+        ]
+
+        # Priority level 1 packet - Trigger ack
+        if with_trigger_ack:
+            self.submodules.trig_ack = trig_ack = Trigger_ACK_Inserter()
+            self.comb += self.trig_ack_stb.eq(trig_ack.stb)
+        
+        # Priority level 2 packet - command and test packet
+        # Control is not timing dependent, all the data packets are handled in firmware
+        self.submodules.writer = writer = Command_Test_Packet_Writer(command_buffer_depth)
+
+        # writer memory control interface
+        self.writer_word_len = CSRStorage(log2_int(command_buffer_depth))
+        self.writer_stb = CSR()
+        self.writer_stb_testseq = CSR()
+        self.writer_busy = CSRStatus()
+
+        self.sync += [
+            writer.word_len.eq(self.writer_word_len.storage),
+            writer.stb.eq(self.writer_stb.re),
+            writer.stb_testseq.eq(self.writer_stb_testseq.re),
+            self.writer_busy.status.eq(writer.busy),
+        ]
+
+        # Misc
+        self.submodules.pak_wrp = pak_wrp = Packet_Wrapper()
+        self.submodules.idle = idle = Idle_Word_Inserter()
+        self.submodules.converter = converter = StrideConverter(word_layout, char_layout)
+
+        if with_trigger_ack:
+            tx_pipeline = [writer, pak_wrp, idle, trig_ack, converter, trig, phy]
+        else:
+            tx_pipeline = [writer, pak_wrp, idle, converter, trig, phy]
+
+        for s, d in zip(tx_pipeline, tx_pipeline[1:]):
+            self.comb += s.source.connect(d.sink)
+
+class CXP_Frame_Pipeline(Module, AutoCSR):
+    # optimal stream packet size is 2 KiB - Section 9.5.2 (CXP-001-2021)
+    def __init__(self, pipelines, pmod_pads, roi_engine_count=1, res_width=16, count_width=31, master=0, packet_size=16384):
+        n_channels = len(pipelines)
+        assert n_channels > 0
+        assert count_width <= 31
+
+        # Trigger rtio
+        nbit_trigdelay = 8
+        nbit_linktrig = 1
+        self.trigger = rtlink.Interface(
+            rtlink.OInterface(nbit_trigdelay + nbit_linktrig),
+            rtlink.IInterface(word_width, timestamped=False)
+        )
+
+        self.sync.rio += [
+            If(self.trigger.o.stb,
+                pipelines[master].tx.trig_delay.eq(self.trigger.o.data[nbit_linktrig:]),
+                pipelines[master].tx.trig_linktrigger_mode.eq(self.trigger.o.data[:nbit_linktrig]),
+            ),
+            pipelines[master].tx.trig_stb.eq(self.trigger.o.stb),
+        ]
+
+
+        # ROI rtio
+         
+        # 4 cfg (x0, y0, x1, y1) per roi_engine
+        self.config = rtlink.Interface(rtlink.OInterface(res_width, bits_for(4*roi_engine_count-1)))
+
+        # select which roi engine can output rtio_input signal
+        self.gate_data = rtlink.Interface(
+            rtlink.OInterface(roi_engine_count),
+            # the 32th bits is for sentinel (gate detection)
+            rtlink.IInterface(count_width+1, timestamped=False)
+        )
+
+        self.crc_error_cnt = CSRStatus(16)
+        self.crc_error_reset = CSR()
+
+        # DEBUG: csr
+        self.arbiter_active_ch = CSRStatus(n_channels)
+
+        self.roi_counter = CSRStatus(count_width)
+        self.roi_update = CSR()
+        self.pix_y = CSRStatus(res_width)
+
+        self.header_l_size = CSRStatus(3*char_width)
+        self.header_x_size = CSRStatus(3*char_width)
+        self.header_y_size = CSRStatus(3*char_width)
+        self.header_new_line = CSRStatus(3*char_width)
+        
+        # # #
+        
+        cdr = ClockDomainsRenamer("cxp_gtx_rx")
+    
+        debug_out = False
+
+        if not debug_out:
+            self.submodules.pixel_pipeline = pixel_pipeline = cdr(Pixel_Pipeline(res_width, count_width, packet_size))
+
+            # CRC error counter
+            self.submodules.crc_reset_ps = crc_reset_ps = PulseSynchronizer("sys", "cxp_gtx_rx")
+            self.comb += crc_reset_ps.i.eq(self.crc_error_reset.re)
+
+            crc_error_cnt_rx = Signal.like(self.crc_error_cnt.status)
+
+            crc_error_r = Signal()
+            self.sync.cxp_gtx_rx += [
+                # to improve timinig
+                crc_error_r.eq(pixel_pipeline.crc_checker.error),
+
+                If(crc_reset_ps.o,
+                    crc_error_cnt_rx.eq(crc_error_cnt_rx.reset),
+                ).Elif(crc_error_r,
+                    crc_error_cnt_rx.eq(crc_error_cnt_rx + 1),
+                ),
+            ]
+            self.specials += MultiReg(crc_error_cnt_rx, self.crc_error_cnt.status)
+
+            # RTIO interface
+
+            n = 0
+            cfg = pixel_pipeline.roi.cfg
+            for offset, target in enumerate([cfg.x0, cfg.y0, cfg.x1, cfg.y1]):
+                roi_boundary = Signal.like(target)
+                self.sync.rio += If(self.config.o.stb & (self.config.o.address == 4*n+offset),
+                                roi_boundary.eq(self.config.o.data))
+                self.specials += MultiReg(roi_boundary, target, "cxp_gtx_rx")
+
+
+
+            roi_out = pixel_pipeline.roi.out
+            update = Signal()
+            self.submodules.ps = ps = PulseSynchronizer("cxp_gtx_rx", "sys")
+            self.sync.cxp_gtx_rx += ps.i.eq(roi_out.update)
+            self.sync += update.eq(ps.o)
+
+            sentinel = 2**count_width
+            count_sys = Signal.like(roi_out.count)
+
+            self.specials += MultiReg(roi_out.count, count_sys),
+            self.sync.rio += [
+                # TODO: add gating
+                self.gate_data.i.stb.eq(update),
+                # without the slice, unspecified bits will be 1 for some reason
+                # i.e. data[count_wdith:] = 0b111111... when using data.eq(count_sys)
+                self.gate_data.i.data[:count_width].eq(count_sys),
+            ]
+
+            
+
+            # TODO: fix count_sys seems like end of frame is broken
+            # BUG: it maybe related to the KCode bug that only happens after frameheader decoder COPY (i.e. when sending pixel data)
+            # DEBUG:
+
+            new_line_cnt_rx, new_line_cnt_sys = Signal(3*char_width), Signal(3*char_width)
+            l_size_rx, l_size_sys = Signal(3*char_width), Signal(3*char_width)
+            x_size_rx, x_size_sys = Signal(3*char_width), Signal(3*char_width)
+            y_size_rx, y_size_sys = Signal(3*char_width), Signal(3*char_width)
+            y_pix_rx, y_pix_sys = Signal(res_width), Signal(res_width)
+            self.sync.cxp_gtx_rx += [
+                If(pixel_pipeline.header_decoder.new_line,
+                    new_line_cnt_rx.eq(new_line_cnt_rx + 1),
+                ),
+
+                l_size_rx.eq(pixel_pipeline.header_decoder.metadata.l_size),
+                x_size_rx.eq(pixel_pipeline.header_decoder.metadata.x_size),
+                y_size_rx.eq(pixel_pipeline.header_decoder.metadata.y_size),                
+
+                y_pix_rx.eq(pixel_pipeline.parser.pixel4x[0].y),
+            ]
+            self.specials += [
+                MultiReg(new_line_cnt_rx, new_line_cnt_sys),
+                MultiReg(l_size_rx, l_size_sys),
+                MultiReg(x_size_rx, x_size_sys),
+                MultiReg(y_size_rx, y_size_sys),
+                MultiReg(y_pix_rx, y_pix_sys),
+            ]
+            self.sync += [
+                self.header_new_line.status.eq(new_line_cnt_sys),
+                self.pix_y.status.eq(y_pix_sys),
+                self.header_l_size.status.eq(l_size_sys),
+                self.header_x_size.status.eq(x_size_sys),
+                self.header_y_size.status.eq(y_size_sys),
+                self.roi_counter.status.eq(count_sys),
+                If(update,
+                    self.roi_update.w.eq(1),
+                ).Elif(self.roi_update.re,
+                    self.roi_update.w.eq(0),
+                ),
+            ]
+
+        else:
+            # DEBUG:
+            crc_checker = cdr(CXPCRC32_Checker())
+
+            # TODO: handle full buffer gracefully
+            # TODO: investigate why there is a heartbeat message in the middle of the frame with k27.7 code too???
+            # NOTE: sometimes there are 0xFBFBFBFB K=0b1111
+            # perhaps the buffer is full overflowing and doing strange stuff             
+
+            # it should be mem block not "cycle buffer"
+            # self.submodules.dropper = dropper = cdr(DChar_Dropper())
+            buffer = cdr(Buffer(word_layout_dchar)) # crcchecker timinig is bad
+            buffer_cdc_fifo = cdr(Buffer(word_layout_dchar)) # to improve timing
+            cdc_fifo = stream.AsyncFIFO(word_layout_dchar, 2**log2_int(packet_size//word_width))
+            self.submodules += buffer, crc_checker, buffer_cdc_fifo
+            self.submodules += ClockDomainsRenamer({"write": "cxp_gtx_rx", "read": "sys"})(cdc_fifo)
+            self.submodules.debug_out = debug_out = RX_Debug_Buffer(word_layout_dchar, 2**log2_int(packet_size//word_width))
+
+            pipeline = [buffer, crc_checker, buffer_cdc_fifo, cdc_fifo, debug_out]
+            for s, d in zip(pipeline, pipeline[1:]):
+                self.comb += s.source.connect(d.sink)
+
+
+
+        # Routing WIP
+        #                        +---------+     +-------------+
+        # downconn pipline ----->|         |     |             |------> crc checker ------> raw stream data 
+        #                        | arbiter |---->| broadcaster |
+        # downconn pipline ----->|         |     |             |------> crc checker ------> raw stream data 
+        #                        +---------+     +-------------+
+        #
+
+
+        self.submodules.arbiter = arbiter = cdr(Stream_Arbiter(n_channels))
+        self.submodules.broadcaster = broadcaster = cdr(Stream_Broadcaster())
+
+        # Connect pipeline
+        for i, p in enumerate(pipelines):
+            # Assume downconns pipeline already marks the eop
+            self.comb += p.rx.source.connect(arbiter.sinks[i])
+
+        self.comb += arbiter.source.connect(broadcaster.sink)
+
+        if not debug_out:
+            self.comb += broadcaster.sources[0].connect(pixel_pipeline.sink),
+        else:
+            self.comb += broadcaster.sources[0].connect(pipeline[0].sink),
+
+        # Control interface
+        # only the simple topology MASTER:ch0, extension:ch1,2,3 is supported right now
+        active_channels_sys = Signal(n_channels)
+        for i, p in enumerate(pipelines):
+            # TODO: change this to non csr signal?
+            self.sync += active_channels_sys[i].eq(p.rx.active)
+        self.specials += MultiReg(active_channels_sys, arbiter.active_channels, odomain="cxp_gtx_rx"),
+
+        # DEBUG:
+        self.sync += self.arbiter_active_ch.status.eq(active_channels_sys)
+
+        for i, p in enumerate(pipelines):
+            # self.comb += p.rx.source.ack.eq(1)
+
+            rx_stb = Signal()
+            self.sync.cxp_gtx_rx += rx_stb.eq(p.rx.source.stb)
+            self.specials += [
+                # Instance("OBUF", i_I=rx_stb, o_O=pmod_pads[i]),
+                # Instance("OBUF", i_I=arbiter.sinks[i].stb, o_O=pmod_pads[i]),
+            ]
+
+class NEO_CXP_Frame_pipeline(Module):
+    # optimal stream packet size is 2 KiB - Section 9.5.2 (CXP-001-2021)
+    def __init__(self, pipelines, pmod_pads, roi_engine_count=1, res_width=16, count_width=31, master=0, packet_size=16384):
+        n_channels = len(pipelines)
+        assert n_channels > 0
+        assert count_width <= 31
+
+        # Trigger rtio
+        nbit_trigdelay = 8
+        nbit_linktrig = 1
+        self.trigger = rtlink.Interface(
+            rtlink.OInterface(nbit_trigdelay + nbit_linktrig),
+            rtlink.IInterface(word_width, timestamped=False)
+        )
+
+        self.sync.rio += [
+            If(self.trigger.o.stb,
+                pipelines[master].tx.trig.delay.eq(self.trigger.o.data[nbit_linktrig:]),
+                pipelines[master].tx.trig.linktrig_mode.eq(self.trigger.o.data[:nbit_linktrig]),
+            ),
+            pipelines[master].tx.trig.stb.eq(self.trigger.o.stb),
+        ]
+
+        
+        # ROI rtio
+         
+        # 4 cfg (x0, y0, x1, y1) per roi_engine
+        self.config = rtlink.Interface(rtlink.OInterface(res_width, bits_for(4*roi_engine_count-1)))
+
+        # select which roi engine can output rtio_input signal
+        self.gate_data = rtlink.Interface(
+            rtlink.OInterface(roi_engine_count),
+            # the 32th bits is for sentinel (gate detection)
+            rtlink.IInterface(count_width+1, timestamped=False)
+        )
+
+       
+        # # #
+        
+        cdr = ClockDomainsRenamer("cxp_gtx_rx")
+    
+        debug_out = False
+
+        if debug_out:
+            pass
+
+
+        #
+        # downconn pipline -----> router -----> arbiter ------> crc checker ------> 4x converters
+        #
+
+        # Connect pipeline
+        for i, p in enumerate(pipelines):
+            broadcaster = cdr(cxp_router.Stream_Router()) # strip the packet id, tag & packet size
+            crc_checker = cdr(CXPCRC32_Checker())
+            self.submodules += broadcaster, crc_checker
+
+            self.comb += [
+                p.rx.source.connect(broadcaster.sink),
+                broadcaster.sources[0].connect(crc_checker),
+            ]