Add support for Seatalk1 on Raspberry Pi 5

packages/server-admin-ui/src/views/ServerConfig/BasicProvider.js

@@ -1022,7 +1022,24 @@ const gpios = [
 const Seatalk = (props) => (
   <span>
     <FormGroup row>
-      <Col md="2">
+      <Col md="3">
+        <Label htmlFor="options.type">GPIO Library</Label>
+      </Col>
+      <Col xs="12" md="3">
+        <Input
+          type="select"
+          value={props.value.options.type || 'none'}
+          name="options.type"
+          onChange={(event) => props.onChange(event)}
+        >
+          <option value="none">Select a library</option>
+          <option value="gpiod">gpiod</option>
+          <option value="pigpio">pigpio (legacy)</option>
+        </Input>
+      </Col>
+    </FormGroup>
+    <FormGroup row>
+      <Col md="3">
         <Label htmlFor="gpio">GPIO Pin</Label>
       </Col>
       <Col xs="12" md="3">
@@ -1040,7 +1057,7 @@ const Seatalk = (props) => (
       </Col>
     </FormGroup>
     <FormGroup row>
-      <Col md="2">
+      <Col md="3">
         <Label htmlFor="gpioInvert">Invert signal</Label>
       </Col>
       <Col xs="12" md="10">

packages/streams/gpiod-seatalk.js

@@ -0,0 +1,353 @@
+/*
+ * Copyright 2024 Adrian Studer
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * This stream receives Seatalk1 data over GPIO on a Raspberry Pi
+ * Supports Python libraries gpiod 1.x and 2.x
+ * Supports Raspberry Pi OS Bookworm and Bullseye on Raspberry Pi 3, 4 and 5
+*/
+
+const Execute = require('./execute')
+
+const cmd = `
+import gpiod, sys, datetime
+
+ST_PIN = 20
+
+ST_INVERT = 0   # 0=idle high, 1=idle low
+ST_BITS = 9
+ST_STOP = 1
+ST_BAUD = 4800
+
+# detect version of gpiod,
+gpiod_v = int(gpiod.__version__.split(".")[0])
+if gpiod_v != 1 and gpiod_v !=2:
+    print("Error: gpiod version {} is not supported".format(gpiod.__version__))
+    sys.exit()
+
+# detect model of Raspberry Pi, tested with Pi 4 and Pi 5 running Bookworm
+with open("/proc/device-tree/model") as f:
+    model = f.read()
+if "Pi 4" in model or "Pi 3" in model:
+    gpio_chip = "gpiochip0"
+elif "Pi 5" in model:
+    gpio_chip = "gpiochip4"
+else:
+    print("Warning: Use of {} is untested".format(model))
+    gpio_chip = "gpiochip0"
+
+class st1rx:
+    line = None
+    pending_e = None
+
+    def open(self, pin, baud=ST_BAUD, bits=ST_BITS, stop=ST_STOP, invert=ST_INVERT):
+        self.baud = baud
+        self.bits = bits
+        self.stop = stop
+        self.invert = invert
+
+        if gpiod_v == 1:
+            # get pin with gpiod v1.x.x
+            if self.invert == 0:
+                pull = gpiod.LINE_REQ_FLAG_BIAS_PULL_UP
+            else:
+                pull = gpiod.LINE_REQ_FLAG_BIAS_PULL_DOWN
+            chip = gpiod.Chip(gpio_chip)
+            self.line = chip.get_line(pin)
+            if self.line is None:
+                print("Error connecting to pin ", pin)
+                return False
+            self.line.request(
+                consumer="ST1RX",
+                type=gpiod.LINE_REQ_EV_BOTH_EDGES,
+                flags=pull)
+        else:
+            # get pin with gpiod v2.x.x
+            if self.invert == 0:
+                pull = gpiod.line.Bias.PULL_UP
+            else:
+                pull = gpiod.line.Bias.PULL_DOWN
+            self.line = gpiod.request_lines(
+                "/dev/" + gpio_chip,
+                consumer="ST1RX",
+                config={pin: gpiod.LineSettings(edge_detection=gpiod.line.Edge.BOTH, bias=pull)}
+                )
+
+        self.pending_e = None
+        return True
+
+    def close(self):
+        if self.line is not None:
+            self.line.release()
+        self.line = None
+
+    def read_gpiod1(self):
+        l = self.line
+        level = 0
+        data = 0
+        bits = self.bits
+        stop = self.stop
+        pol = self.invert
+        fullbit_ns = int(1000000000 / self.baud)
+        halfbit_ns = int(fullbit_ns / 2)
+        frame_ns = int((1 + self.bits + self.stop) * fullbit_ns)
+
+        if self.pending_e is None:
+            # wait for new gpio events, timeout after 0.5 seconds
+            if l.event_wait(nsec=500000000) == False:
+                # no activity, return None
+                return
+            e = l.event_read()
+        else:
+            # we got a pending event
+            e = self.pending_e
+            self.pending_e = None
+
+        if e.type == e.FALLING_EDGE:
+            level = 0^pol
+        else:
+            level = 1^pol
+        e_ns = e.nsec
+
+        sample_ns = e_ns + halfbit_ns
+        remaining_ns = frame_ns + halfbit_ns
+        b = 0
+        sb = False
+
+        while True:
+            # wait for next event
+            if l.event_wait(nsec=remaining_ns):
+                e = l.event_read()
+                e_ns = e.nsec
+                if e_ns < sample_ns:
+                    e_ns += 1000000000
+
+                # process bits since previous event
+                while sample_ns < e_ns:
+                    if sb == False:
+                        if level == 0:
+                            sb = True
+                        else:
+                            # not a start bit, return None
+                            print("not a start bit")
+                            return
+                    elif b < bits:
+                        # store data bits
+                        data |= level << b
+                        b += 1
+                    elif stop > 0:
+                        # check stop bits
+                        if level == 1:
+                            stop -= 1
+                        else:
+                            # invalid stop bit
+                            print("invalid stop bits")
+                            return
+                    sample_ns += fullbit_ns
+                    remaining_ns -= fullbit_ns
+
+                # new level going forward
+                if e.type == e.FALLING_EDGE:
+                    level = 0^pol
+                else:
+                    level = 1^pol
+
+                # check if we are done processing this event
+                if remaining_ns < fullbit_ns:
+                    # if so, this event is already start of next frame
+                    self.pending_e = e
+                    break
+            else:
+                # timeout is end of frame
+                if level == 0:
+                    # invalid idle state at end of frame
+                    print("invalid idle state")
+                    return
+                # add remaining bits to byte
+                while b < bits:
+                    data |= level << b
+                    b += 1
+                stop = 0
+                break
+
+        if stop == 0 and b == bits:
+            return data
+        else:
+            # missing stop or data bits
+            print("missing stop or data bits")
+            return
+
+    def read_gpiod2(self):
+        l = self.line
+        level = 0
+        data = 0
+        bits = self.bits
+        stop = self.stop
+        pol = self.invert
+        fullbit_ns = int(1000000000 / self.baud)
+        halfbit_ns = int(fullbit_ns / 2)
+        frame_ns = int((1 + self.bits + self.stop) * fullbit_ns)
+
+        if self.pending_e is None:
+            # wait for new gpio events, timeout after 0.5 seconds
+            if l.wait_edge_events(datetime.timedelta(microseconds=500000)) == False:
+                # no activity, return None
+                return
+            e = l.read_edge_events(1)[0]
+        else:
+            # we got a pending event
+            e = self.pending_e
+            self.pending_e = None
+
+        if e.event_type == e.Type.FALLING_EDGE:
+            level = 0^pol
+        else:
+            level = 1^pol
+        e_ns = e.timestamp_ns
+
+        sample_ns = e_ns + halfbit_ns
+        remaining_ns = frame_ns + halfbit_ns
+        b = 0
+        sb = False
+
+        while True:
+            # wait for next event
+            if l.wait_edge_events(datetime.timedelta(microseconds=remaining_ns/1000)):
+                e = l.read_edge_events(1)[0]
+                e_ns = e.timestamp_ns
+                if e_ns < sample_ns:
+                    e_ns += 1000000000
+
+                # process bits since previous event
+                while sample_ns < e_ns:
+                    if sb == False:
+                        if level == 0:
+                            sb = True
+                        else:
+                            # not a start bit, return None
+                            print("not a start bit")
+                            return
+                    elif b < bits:
+                        # store data bits
+                        data |= level << b
+                        b += 1
+                    elif stop > 0:
+                        # check stop bits
+                        if level == 1:
+                            stop -= 1
+                        else:
+                            # invalid stop bit
+                            print("invalid stop bits")
+                            return
+                    sample_ns += fullbit_ns
+                    remaining_ns -= fullbit_ns
+
+                # new level going forward
+                if e.event_type == e.Type.FALLING_EDGE:
+                    level = 0^pol
+                else:
+                    level = 1^pol
+
+                # check if we are done processing this event
+                if remaining_ns < fullbit_ns:
+                    # if so, this event is already start of next frame
+                    self.pending_e = e
+                    break
+            else:
+                # timeout is end of frame
+                if level == 0:
+                    # invalid idle state at end of frame
+                    print("invalid idle state")
+                    return
+                # add remaining bits to byte
+                while b < bits:
+                    data |= level << b
+                    b += 1
+                stop = 0
+                break
+
+        if stop == 0 and b == bits:
+            return data
+        else:
+            # missing stop or data bits
+            print("missing stop or data bits")
+            return
+
+    def read(self):
+        if self.line is None:
+            print("Error: no pin connected")
+            return
+        if gpiod_v == 1:
+            return self.read_gpiod1()
+        else:
+            return self.read_gpiod2()
+
+if __name__ == "__main__":
+    gpio = ST_PIN
+    if len(sys.argv) > 1:
+        # Gpio, info as "GPIOnn", from GUI setup. Sensing the seatalk1 (yellow wire)
+        gpio = int("".join(filter(str.isdigit, sys.argv[1])))
+    pol = ST_INVERT
+    if len(sys.argv) > 2:
+        # Invert, inverted input from ST1, selected in the GUI
+        if sys.argv[2] == "true":
+            pol = 1
+
+    st = st1rx()
+    if st.open(pin=gpio, invert=pol) == False:
+        print("Error: Failed to open Seatalk1 pin")
+        sys.exit()
+
+    try:
+        st_msg = ""
+        st_start = False
+        while True:
+            # read a byte from Seatalk pin
+            d = st.read()
+            # if error, timeout, or start flag is set
+            if d is None or d > 255:
+                # output pending seatalk data
+                if st_start == True:
+                    print("$STALK" + st_msg)
+                    st_start = False
+                    st_msg = ""
+            # if new data
+            if d is not None:
+                # if start flag is set, start a new msg
+                if d > 255:
+                    st_start = True
+                    st_msg = ""
+                # if a msg is in progress, append byte
+                if st_start == True:
+                    st_msg += ",{:02X}".format(d & 0xff)
+    except Exception as e:
+        print(e)
+    except KeyboardInterrupt:
+        pass
+    st.close()
+    print("exit")
+`
+
+function GpiodSeatalk(options) {
+  const createDebug = options.createDebug || require('debug')
+  Execute.call(this, { debug: createDebug('signalk:streams:gpiod-seatalk') })
+  this.options = options
+  this.options.command = `python -u -c '${cmd}' ${options.gpio} ${options.gpioInvert} `
+}
+
+require('util').inherits(GpiodSeatalk, Execute)
+
+module.exports = GpiodSeatalk