succd: restyle slightly

This improves the structure of the code, separating the data/control
interface out and then implementing the http interface as a user of this
interface.

succbone/succd/http.go

@@ -15,6 +15,10 @@ import (
 	"k8s.io/klog"
 )
 
+type httpServer struct {
+	d daemonController
+}
+
 var (
 	//go:embed index.html
 	templateIndexText string
@@ -23,7 +27,7 @@ var (
 	favicon []byte
 )
 
-func (d *daemon) httpFavicon(w http.ResponseWriter, r *http.Request) {
+func (s *httpServer) viewFavicon(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "image/png")
 	w.Write(favicon)
 }
@@ -50,45 +54,103 @@ func formatMbar(v float32) template.HTML {
 	return template.HTML(res)
 }
 
+// apiData is the data model served to the user via HTTP/WebSockets
+type apiData struct {
+	// Safety interlocks.
+	Safety struct {
+		// Failsafe mode enabled - pirani gauge seems disconnected.
+		Failsafe bool
+		// HighPressure interlock enabled - pressure too high to run diffusion
+		// pump.
+		HighPressure bool
+	}
+	// Pirani gauge data.
+	Pirani struct {
+		// Volts read from the gauge (0-10).
+		Volts string
+		// Mbar read from the gauge, formatted as HTML.
+		Mbar template.HTML
+		// MbarFloat read from the gauge.
+		MbarFloat float32
+	}
+	// Pump state.
+	Pumps struct {
+		// RPOn means the roughing pump is turned on.
+		RPOn bool
+		// DPOn means the diffusion pump is turned on.
+		DPOn bool
+	}
+	// Pressure feedback into evacuation board.
+	Feedback struct {
+		// RoughReached is true when the system has reached a rough vacuum
+		// stage.
+		RoughReached bool
+		// HighReached is true when the system has reached a high vacuum stage.
+		HighReached bool
+	}
+	// System junk.
+	System struct {
+		// Load of the system.
+		Load string
+		// Hostname of the system.
+		Hostname string
+	}
+}
+
+// apiData returns the user data model for the current state of the system. If
+// skipSystem is set, the System subset is ignored (saves system load, and is
+// not being served via websockets).
+func (s *httpServer) apiData(skipSystem bool) *apiData {
+	state := s.d.snapshot()
+	volts, mbar := state.pirani()
+	rough, high := state.vacuumStatus()
+
+	var hostname, load string
+	var err error
+
+	if !skipSystem {
+		hostname, err = os.Hostname()
+		if err != nil {
+			hostname = "unknown"
+		}
+		loadB, err := os.ReadFile("/proc/loadavg")
+		load = "unknown"
+		if err == nil {
+			parts := strings.Fields(string(loadB))
+			load = strings.Join(parts[:3], " ")
+		}
+	}
+
+	ad := apiData{}
+	ad.Safety.Failsafe = state.safety.failsafe
+	ad.Safety.HighPressure = state.safety.highPressure
+	ad.Pirani.Volts = formatVolts(volts)
+	ad.Pirani.Mbar = formatMbar(mbar)
+	ad.Pirani.MbarFloat = mbar
+	ad.Pumps.RPOn = state.rpOn
+	ad.Pumps.DPOn = state.dpOn
+	ad.Feedback.RoughReached = rough
+	ad.Feedback.HighReached = high
+	ad.System.Load = load
+	ad.System.Hostname = hostname
+	return &ad
+}
+
 // httpIndex is the / view.
-func (d *daemon) httpIndex(w http.ResponseWriter, r *http.Request) {
+func (s *httpServer) viewIndex(w http.ResponseWriter, r *http.Request) {
 	if r.URL.Path != "/" {
 		http.NotFound(w, r)
 		return
 	}
 
-	volts, mbar := d.pirani()
-	rp := d.rpGet()
-	dp := d.dpGet()
-  failsafe, highpressure := d.safetyStatusGet()
-
-	loadB, err := os.ReadFile("/proc/loadavg")
-	load := "unknown"
-	if err == nil {
-		parts := strings.Fields(string(loadB))
-		load = strings.Join(parts[:3], " ")
-	}
-
-	hostname, err := os.Hostname()
-	if err != nil {
-		hostname = "unknown"
-	}
-
-	templateIndex.Execute(w, map[string]any{
-		"failsafe":     failsafe,
-		"highpressure": highpressure,
-		"volts":        formatVolts(volts),
-		"mbar":         formatMbar(mbar),
-		"rp":           rp,
-		"dp":           dp,
-		"hostname":     hostname,
-		"load":         load,
-	})
+	data := s.apiData(false)
+	//data.Pirani.Mbar = html.St
+	templateIndex.Execute(w, data)
 }
 
 // httpStream is the websocket clientwards data hose, returning a 10Hz update
 // stream of pressure/voltage.
-func (d *daemon) httpStream(w http.ResponseWriter, r *http.Request) {
+func (s *httpServer) viewStream(w http.ResponseWriter, r *http.Request) {
 	c, err := websocket.Accept(w, r, nil)
 	if err != nil {
 		return
@@ -105,33 +167,7 @@ func (d *daemon) httpStream(w http.ResponseWriter, r *http.Request) {
 			c.Close(websocket.StatusNormalClosure, "")
 			return
 		case <-t.C:
-			// TODO(q3k): don't poll, get notified when new ADC readout is available.
-			volts, mbar := d.pirani()
-			rp := d.rpGet()
-			dp := d.dpGet()
-			rough, high := d.vacuumStatusGet()
-      failsafe, highpressure := d.safetyStatusGet()
-			v := struct {
-        Failsafe     bool
-        HighPressure bool
-				Volts        string
-				Mbar         string
-				MbarFloat    float32
-				RPOn         bool
-				DPOn         bool
-				RoughReached bool
-				HighReached  bool
-			}{
-        Failsafe:     failsafe,
-        HighPressure: highpressure,
-				Volts:        formatVolts(volts),
-				Mbar:         string(formatMbar(mbar)),
-				MbarFloat:    mbar,
-				RPOn:         rp,
-				DPOn:         dp,
-				RoughReached: rough,
-				HighReached:  high,
-			}
+			v := s.apiData(true)
 			if err := wsjson.Write(ctx, c, v); err != nil {
 				klog.Errorf("Websocket write failed: %v", err)
 				return
@@ -141,39 +177,54 @@ func (d *daemon) httpStream(w http.ResponseWriter, r *http.Request) {
 }
 
 // httpMetrics serves minimalistic Prometheus-compatible metrics.
-func (d *daemon) httpMetrics(w http.ResponseWriter, r *http.Request) {
+func (s *httpServer) viewMetrics(w http.ResponseWriter, r *http.Request) {
 	// TODO(q3k): also serve Go stuff using the actual Prometheus metrics client
 	// library.
-	_, mbar := d.pirani()
+	// TODO(q3k): serve the rest of the data model
+	state := s.d.snapshot()
+	_, mbar := state.pirani()
 	fmt.Fprintf(w, "# HELP sem_pressure_mbar Pressure in the SEM chamber, in millibar\n")
 	fmt.Fprintf(w, "# TYPE sem_pressure_mbar gauge\n")
 	fmt.Fprintf(w, "sem_pressure_mbar %f\n", mbar)
 }
 
-func (d *daemon) httpRoughingPumpEnable(w http.ResponseWriter, r *http.Request) {
-	d.rpSet(true)
+func (s *httpServer) viewRoughingPumpEnable(w http.ResponseWriter, r *http.Request) {
+	s.d.rpSet(true)
 	fmt.Fprintf(w, "succ on\n")
 }
 
-func (d *daemon) httpRoughingPumpDisable(w http.ResponseWriter, r *http.Request) {
-	d.rpSet(false)
+func (s *httpServer) viewRoughingPumpDisable(w http.ResponseWriter, r *http.Request) {
+	s.d.rpSet(false)
 	fmt.Fprintf(w, "succ off\n")
 }
 
-func (d *daemon) httpDiffusionPumpEnable(w http.ResponseWriter, r *http.Request) {
-	d.dpSet(true)
+func (s *httpServer) viewDiffusionPumpEnable(w http.ResponseWriter, r *http.Request) {
+	s.d.dpSet(true)
 	fmt.Fprintf(w, "deep succ on\n")
 }
 
-func (d *daemon) httpDiffusionPumpDisable(w http.ResponseWriter, r *http.Request) {
-	d.dpSet(false)
+func (s *httpServer) viewDiffusionPumpDisable(w http.ResponseWriter, r *http.Request) {
+	s.d.dpSet(false)
 	fmt.Fprintf(w, "deep succ off\n")
 }
 
-func (d *daemon) httpButtonPumpDown(w http.ResponseWriter, r *http.Request) {
-	d.pumpDownPress()
+func (s *httpServer) viewButtonPumpDown(w http.ResponseWriter, r *http.Request) {
+	s.d.pumpDownPress()
 }
 
-func (d *daemon) httpButtonVent(w http.ResponseWriter, r *http.Request) {
-	d.ventPress()
+func (s *httpServer) viewButtonVent(w http.ResponseWriter, r *http.Request) {
+	s.d.ventPress()
+}
+
+func (s *httpServer) setupViews() {
+	http.HandleFunc("/", s.viewIndex)
+	http.HandleFunc("/favicon.png", s.viewFavicon)
+	http.HandleFunc("/stream", s.viewStream)
+	http.HandleFunc("/metrics", s.viewMetrics)
+	http.HandleFunc("/button/vent", s.viewButtonVent)
+	http.HandleFunc("/button/pumpdown", s.viewButtonPumpDown)
+	http.HandleFunc("/rp/on", s.viewRoughingPumpEnable)
+	http.HandleFunc("/rp/off", s.viewRoughingPumpDisable)
+	http.HandleFunc("/dp/on", s.viewDiffusionPumpEnable)
+	http.HandleFunc("/dp/off", s.viewDiffusionPumpDisable)
 }

succbone/succd/index.html

@@ -10,6 +10,10 @@ body {
 }
 table {
     font-size: 40px;
+    margin-top: 1em;
+}
+table.status td {
+    width: 2em;
 }
 th, td {
     background-color: #e8e8e8;
@@ -58,50 +62,66 @@ td > span {
 <p style="margin-top: 2em; clear: both;">
     <table>
         <tr>
+            <th rowspan="2">Pirani Gauge</th>
             <th>Voltage</th>
-            <td id="volts" colspan="4">{{.volts}}</td>
+            <td id="volts">{{ .Pirani.Volts }}</td>
         </tr>
         <tr>
             <th>Pressure</th>
-            <td id="mbar" colspan="4">{{.mbar}}</td>
+            <td id="mbar">{{ .Pirani.Mbar }}</td>
         </tr>
+    </table>
+
+    <table class="status">
         <tr>
             <th>Thresholds</th>
-            <td>Rough:</td>
-            <td id="trough">...</td>
-            <td>High:</td>
-            <td id="thigh">...</td>
+            <th>Rough</th>
+            <td id="trough">{{ if .Feedback.RoughReached }}OK{{ else }}NOK{{ end }}</td>
+            <th>High</th>
+            <td id="thigh">{{ if .Feedback.HighReached }}OK{{ else }}NOK{{ end }}</td>
         </tr>
         <tr>
             <th>Pumps</th>
-            <td>RP:</td>
-            <td id="rp">{{ if .rp }}ON{{ else }}OFF{{ end }}</td>
-            <td>DP:</td>
-            <td id="dp">{{ if .dp }}ON{{ else }}OFF{{ end }}</td>
+            <th>RP</th>
+            <td id="rp">{{ if .Pumps.RPOn }}ON{{ else }}OFF{{ end }}</td>
+            <th>DP</th>
+            <td id="dp">{{ if .Pumps.DPOn }}ON{{ else }}OFF{{ end }}</td>
         </tr>
         <tr>
-            <th>Evac Control</th>
-            <td colspan="4">
+            <th>Safety</th>
+            <th style="font-size: 0.7em;">Pirani<br />Failsafe</th>
+            <td id="failsafe">{{ if .Safety.Failsafe }}ON{{ else }}OFF{{ end }}</td>
+            <th style="font-size: 0.7em;">DP<br />Lockout</th>
+            <td id="highpressure">{{ if .Safety.HighPressure }}ON{{ else }}OFF{{ end }}</td>
+        </tr>
+    </table>
+
+    <table>
+        <tr>
+            <th rowspan="3">Control</th>
+            <th>RP</th>
+            <td>
+                <button id="rpon">On</button>
+                <button id="rpoff">Off</button>
+            </td>
+        </tr>
+        <tr>
+            <th>DP</th>
+            <td>
+                <button id="dpon">On</button>
+                <button id="dpoff">Off</button>
+            </td>
+        </tr>
+        <tr>
+            <td colspan="2">
                 <button id="pd">Pump Down</button>
                 <button id="vent">Vent</button>
-                <button id="rpon">RP On</button>
-                <button id="rpoff">RP Off</button>
-                <button id="dpon">DP On</button>
-                <button id="dpoff">DP Off</button>
             </td>
         </tr>
         <tr>
             <th>Status</th>
             <td id="status" colspan="4">OK</td>
         </tr>
-        <tr>
-            <th>Failsafe</th>
-            <td id="failsafe" colspan="4">OK</td>
-        </tr>
-        <tr>
-            <th>Diffusion Pump Lockout</th>
-            <td id="highpressure" colspan="4">OK</td>
-        </tr>
     </table>
 </p>
 <p style="margin-top: 2em;">
@@ -109,7 +129,7 @@ td > span {
 </p>
 
 <p style="font-style: italic; font-size: 12px; margin-top: 5em;">
-    {{.hostname}} | load: {{.load}} | <a href="/debug/pprof">pprof</a> | <a href="/metrics">metrics</a> | ws ping: <span id="ping">…</span>
+    {{ .System.Hostname }} | load: {{ .System.Load }} | <a href="/debug/pprof">pprof</a> | <a href="/metrics">metrics</a> | ws ping: <span id="ping">…</span>
 </p>
 
 <script>
@@ -288,50 +308,53 @@ window.addEventListener("load", (_) => {
         });
         socket.addEventListener("message", (event) => {
             const data = JSON.parse(event.data);
-            volts.innerHTML = data.Volts;
-            mbar.innerHTML = data.Mbar;
-            failsafe.innerHTML = data.Failsafe ? "ON" : "OFF";
-            if (data.Failsafe) {
+            volts.innerHTML = data.Pirani.Volts;
+            mbar.innerHTML = data.Pirani.Mbar;
+            if (data.Safety.Failsafe) {
+                failsafe.innerHTML = "ON";
                 failsafe.style = "background-color: #f06060";
             } else {
+                failsafe.innerHTML = "OFF";
                 failsafe.style = "background-color: #60f060";
             }
-            if (data.HighPressure) {
+            if (data.Safety.HighPressure) {
                 highpressure.innerHTML = "ON";
                 highpressure.style =  "background-color: #f06060";
             } else {
                 highpressure.innerHTML = "OFF";
                 highpressure.style = "background-color: #60f060";
             }
-            rp.innerHTML = data.RPOn ? "ON" : "OFF";
-            if (data.RPOn) {
+            if (data.Pumps.RPOn) {
+                rp.innerHTML = "ON";
                 rp.style = "background-color: #60f060";
             } else {
+                rp.innerHTML = "OFF";
                 rp.style = "background-color: #f06060";
             }
-            dp.innerHTML = data.DPOn ? "ON" : "OFF";
-            if (data.DPOn) {
+            if (data.Pumps.DPOn) {
+                dp.innerHTML = "ON";
                 dp.style = "background-color: #60f060";
             } else {
+                dp.innerHTML = "OFF";
                 dp.style = "background-color: #f06060";
             }
 
             let t = [];
-            if (data.RoughReached) {
+            if (data.Feedback.RoughReached) {
                 trough.innerHTML = "OK";
                 trough.style = "background-color: #60f060";
             } else {
                 trough.innerHTML = "NOK";
                 trough.style = "background-color: #f06060";
             }
-            if (data.HighReached) {
+            if (data.Feedback.HighReached) {
                 thigh.innerHTML = "OK";
                 thigh.style = "background-color: #60f060";
             } else {
                 thigh.innerHTML = "NOK";
                 thigh.style = "background-color: #f06060";
             }
-            historicalPush(data.MbarFloat);
+            historicalPush(data.Pirani.MbarFloat);
             ping.innerHTML = Date.now();
         });
         socket.addEventListener("close", (event) => {

succbone/succd/main.go

@@ -26,9 +26,9 @@ func main() {
 
 	ctx, _ := signal.NotifyContext(context.Background(), os.Interrupt)
 
-	d := daemon{
-		rpOn: true,
-	}
+	d := daemon{}
+	d.daemonState.rpOn = true
+
 	d.aboveRough.threshold = float64(flagPressureThresholdRough)
 	d.aboveHigh.threshold = float64(flagPressureThresholdHigh)
 	if flagFake {
@@ -65,16 +65,10 @@ func main() {
 		}
 	}
 
-	http.HandleFunc("/", d.httpIndex)
-	http.HandleFunc("/favicon.png", d.httpFavicon)
-	http.HandleFunc("/stream", d.httpStream)
-	http.HandleFunc("/metrics", d.httpMetrics)
-	http.HandleFunc("/button/vent", d.httpButtonVent)
-	http.HandleFunc("/button/pumpdown", d.httpButtonPumpDown)
-	http.HandleFunc("/rp/on", d.httpRoughingPumpEnable)
-	http.HandleFunc("/rp/off", d.httpRoughingPumpDisable)
-	http.HandleFunc("/dp/on", d.httpDiffusionPumpEnable)
-	http.HandleFunc("/dp/off", d.httpDiffusionPumpDisable)
+	httpServer := httpServer{
+		d: &d,
+	}
+	httpServer.setupViews()
 
 	klog.Infof("Listening for HTTP at %s", flagListenHTTP)
 	go func() {

succbone/succd/process.go

@@ -4,22 +4,18 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"math"
 	"sync"
 	"time"
 
 	"k8s.io/klog"
 )
 
-// daemon is the main state of the succdaemon.
+// daemon is the main service of the succdaemon.
 type daemon struct {
 	// adcPirani is the adc implementation returning the voltage of the Pfeiffer
 	// Pirani gauge.
 	adcPirani adc
 
-	failsafe     bool
-	highPressure bool
-
 	gpioDiffusionPump gpio
 	gpioRoughingPump  gpio
 	gpioBtnPumpDown   gpio
@@ -27,18 +23,9 @@ type daemon struct {
 	gpioBelowRough    gpio
 	gpioBelowHigh     gpio
 
-	// mu guards state variables below.
+	// mu guards the state below.
 	mu sync.RWMutex
-	// adcPiraniVolts is a moving window of read ADC values, used to calculate a
-	// moving average.
-	adcPiraniVolts []float32
-	rpOn           bool
-	dpOn           bool
-
-	vent       momentaryOutput
-	pumpdown   momentaryOutput
-	aboveRough thresholdOutput
-	aboveHigh  thresholdOutput
+	daemonState
 }
 
 // momentaryOutput is an output that can be triggered for 500ms.
@@ -119,44 +106,47 @@ func (d *daemon) processOnce(_ context.Context) error {
 	d.pumpdown.process()
 	d.vent.process()
 
-	_, mbar := d.piraniUnlocked()
+	_, mbar := d.daemonState.pirani()
 	d.aboveRough.process(float64(mbar))
 	d.aboveHigh.process(float64(mbar))
 
-	if d.piraniWireBreakDetection() {
+	// Check if the pirani gauge is disconnected. Note: this will assume the
+	// pirani gauge is connected for the first couple of processing runs as
+	// samples are still being captured.
+	if d.piraniDetection() == piraniDetectionDisconnected {
 		// Unrealistic result, Pirani probe probably disconnected. Failsafe mode.
-		if !d.failsafe {
-			d.failsafe = true
+		if !d.safety.failsafe {
+			d.safety.failsafe = true
 			klog.Errorf("Pirani probe seems disconnected; enabling failsafe mode")
 		}
 	} else {
-		if d.failsafe {
+		if d.safety.failsafe {
 			if mbar >= 1e2 {
-				d.failsafe = false
+				d.safety.failsafe = false
 				klog.Infof("Values are plausible again; quitting failsafe mode")
 			}
 		}
 	}
 
 	if mbar >= 1e-1 {
-		if !d.highPressure {
-			d.highPressure = true
+		if !d.safety.highPressure {
+			d.safety.highPressure = true
 			klog.Errorf("Pressure is too high; enabling diffusion pump lockout")
 		}
-	} else {
-		if d.highPressure {
-			d.highPressure = false
+	} else if mbar < (1e-1)-(1e-2) {
+		if d.safety.highPressure {
+			d.safety.highPressure = false
 			klog.Infof("Pressure is low enough for diffusion pump operation; quitting diffusion pump lockout")
 		}
 	}
 
-	if d.failsafe {
+	if d.safety.failsafe {
 		d.aboveRough.output = true
 		d.aboveHigh.output = true
 		d.dpOn = false
 	}
 
-	if d.highPressure {
+	if d.safety.highPressure {
 		d.dpOn = false
 	}
 
@@ -190,100 +180,3 @@ func (d *daemon) processOnce(_ context.Context) error {
 
 	return nil
 }
-
-func (d *daemon) piraniWireBreakDetection() bool {
-	if len(d.adcPiraniVolts) < 3 {
-		return true
-	}
-	volts := float32(0.0)
-	for _, v := range d.adcPiraniVolts[len(d.adcPiraniVolts)-3:] {
-		volts += v
-	}
-	volts /= 3.0
-
-	bar := math.Pow(10.0, float64(volts)-8.5)
-	mbar := float32(bar * 1000.0)
-
-	return mbar < 4e-6
-}
-
-// pirani returns the Pirani gauge voltage and pressure.
-func (d *daemon) pirani() (volts float32, mbar float32) {
-	d.mu.RLock()
-	volts, mbar = d.piraniUnlocked()
-	d.mu.RUnlock()
-	return
-}
-
-func (d *daemon) piraniUnlocked() (volts float32, mbar float32) {
-	volts = 0.0
-	for _, v := range d.adcPiraniVolts {
-		volts += v
-	}
-	if len(d.adcPiraniVolts) != 0 {
-		volts /= float32(len(d.adcPiraniVolts))
-	}
-
-	// Per Pirani probe docs.
-	bar := math.Pow(10.0, float64(volts)-8.5)
-	mbar = float32(bar * 1000.0)
-	return
-}
-
-// rpSet enables/disables the roughing pump.
-func (d *daemon) rpSet(state bool) {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	d.rpOn = state
-}
-
-// rpGet returns whether the roughing pump is enabled/disabled.
-func (d *daemon) rpGet() bool {
-	d.mu.RLock()
-	defer d.mu.RUnlock()
-	return d.rpOn
-}
-
-// dpSet enables/disables the diffusion pump.
-func (d *daemon) dpSet(state bool) {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	d.dpOn = state
-}
-
-// dpGet returns whether the diffusion pump is enabled/disabled.
-func (d *daemon) dpGet() bool {
-	d.mu.RLock()
-	defer d.mu.RUnlock()
-	return d.dpOn
-}
-
-func (d *daemon) vacuumStatusGet() (rough, high bool) {
-	d.mu.RLock()
-	defer d.mu.RUnlock()
-	rough = !d.aboveRough.output
-	high = !d.aboveHigh.output
-	return
-}
-
-func (d *daemon) safetyStatusGet() (failsafe, highPressure bool) {
-  d.mu.RLock()
-  defer d.mu.RUnlock()
-  failsafe = d.failsafe
-  highPressure = d.highPressure
-  return
-}
-
-// pumpDownPressed toggles the pump down relay for 500ms.
-func (d *daemon) pumpDownPress() {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	d.pumpdown.trigger()
-}
-
-// ventPress toggles the vent relay for 500ms.
-func (d *daemon) ventPress() {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	d.vent.trigger()
-}

succbone/succd/process_controller.go

@@ -0,0 +1,49 @@
+package main
+
+// daemonController is the control/data interface passed on to external system
+// controllers, eg. the web interface.
+//
+// This is a subset of daemon functions limited to a safe, explicit subset.
+type daemonController interface {
+	// snapshot returns an internally consistent copy of the daemon state.
+	snapshot() *daemonState
+	// rpSet enables/disables the roughing pump.
+	rpSet(bool)
+	// dpSet enables/disables the diffusion pump.
+	dpSet(bool)
+	// pumpDownPress simulates a pumpdown button press.
+	pumpDownPress()
+	// ventPRess simulates a vent button press.
+	ventPress()
+}
+
+func (d *daemon) snapshot() *daemonState {
+	d.mu.RLock()
+	ds := d.daemonState
+	d.mu.RUnlock()
+	return &ds
+}
+
+func (d *daemon) rpSet(state bool) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	d.rpOn = state
+}
+
+func (d *daemon) dpSet(state bool) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	d.dpOn = state
+}
+
+func (d *daemon) pumpDownPress() {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	d.pumpdown.trigger()
+}
+
+func (d *daemon) ventPress() {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	d.vent.trigger()
+}

succbone/succd/process_state.go

@@ -0,0 +1,84 @@
+package main
+
+import "math"
+
+// daemonState contains all the state of the daemon. A copy of it can be
+// requested for consumers, eg. the web view.
+type daemonState struct {
+	safety safetyStatus
+
+	// adcPiraniVolts is a moving window of read ADC values, used to calculate a
+	// moving average.
+	adcPiraniVolts []float32
+	rpOn           bool
+	dpOn           bool
+
+	vent       momentaryOutput
+	pumpdown   momentaryOutput
+	aboveRough thresholdOutput
+	aboveHigh  thresholdOutput
+}
+
+type safetyStatus struct {
+	// failsafe mode is enabled when the pirani gauge appears to be
+	// disconnected, and is disabled only when an atmosphere is read.
+	failsafe bool
+	// highPressure mode is enabled when the pressure reading is above 1e-1
+	// mbar, locking out the diffusion pump from being enabled.
+	highPressure bool
+}
+
+type piraniDetection uint
+
+const (
+	// piraniDetectionUnknown means the system isn't yet sure whether the pirani
+	// gauge is connected.
+	piraniDetectionUnknown piraniDetection = iota
+	// piraniDetectionConnected means the system assumes the pirani gauge is
+	// connected.
+	piraniDetectionConnected = iota
+	// piraniDetectionDisconnected means the system assumes the pirani gauge is
+	// disconnected.
+	piraniDetectionDisconnected = iota
+)
+
+// piraniDetection guesses whether the pirani gauge is connected.
+func (d *daemonState) piraniDetection() piraniDetection {
+	if len(d.adcPiraniVolts) < 3 {
+		return piraniDetectionUnknown
+	}
+	volts := float32(0.0)
+	for _, v := range d.adcPiraniVolts[len(d.adcPiraniVolts)-3:] {
+		volts += v
+	}
+	volts /= 3.0
+
+	bar := math.Pow(10.0, float64(volts)-8.5)
+	mbar := float32(bar * 1000.0)
+
+	if mbar < 4e-6 {
+		return piraniDetectionDisconnected
+	}
+	return piraniDetectionConnected
+}
+
+func (d *daemonState) pirani() (volts float32, mbar float32) {
+	volts = 0.0
+	for _, v := range d.adcPiraniVolts {
+		volts += v
+	}
+	if len(d.adcPiraniVolts) != 0 {
+		volts /= float32(len(d.adcPiraniVolts))
+	}
+
+	// Per Pirani probe docs.
+	bar := math.Pow(10.0, float64(volts)-8.5)
+	mbar = float32(bar * 1000.0)
+	return
+}
+
+func (d *daemonState) vacuumStatus() (rough, high bool) {
+	rough = !d.aboveRough.output
+	high = !d.aboveHigh.output
+	return
+}