pos: hard-reset the device after flashing

esptool-js leaves the chip in the ROM bootloader stub after writeFlash,
so the device appeared dead until power-cycled. Pulse RTS the way
esptool.py does, drop the port (the C3 re-enumerates), and show a
"device restarted" message next to the Connect button.

Co-Authored-By: Claude Fable 5.1 <[email protected]>
Claude-Session: https://claude.ai/code/session_014gVYGi29FjTeLdNTiutkZx

1 files changed, 28 insertions, 0 deletions

diff --git a/src/routes/(app)/pos/+page.svelte b/src/routes/(app)/pos/+page.svelte
index 36869fba..5ad1c99e 100644
--- a/src/routes/(app)/pos/+page.svelte
+++ b/src/routes/(app)/pos/+page.svelte
@@ -70,6 +70,27 @@
     }
   };
 
+  // Pulse RTS to hard-reset the chip out of the ROM bootloader so it boots
+  // the app with the new flash contents. Same sequence esptool.py uses
+  // ("Hard resetting via RTS pin"); on the C3's USB-JTAG-serial port RTS
+  // drives EN, so the device re-enumerates and must be reconnected.
+  let resetDevice = async () => {
+    try {
+      await transport.setDTR(false);
+      await transport.setRTS(true);
+      await new Promise((r) => setTimeout(r, 100));
+      await transport.setRTS(false);
+    } catch (e) {
+      console.warn("reset failed", e);
+    }
+    try {
+      await transport.disconnect();
+    } catch (e) {}
+    esploader = undefined;
+    connected = false;
+    portInfo = "Device reset. Reconnect to flash again.";
+  };
+
   let flashConfig = async () => {
     if (!esploader || !bytes) return;
     if (bytes.length !== 0x20000) {
@@ -92,6 +113,7 @@
     });
 
     configDone = true;
+    await resetDevice();
   };
 
   function onPickFw(e) {
@@ -142,6 +164,7 @@
       });
 
       fwDone = true;
+      await resetDevice();
     } catch (e) {
       console.error(e);
       fwError = e?.message || "Flash failed.";
@@ -156,6 +179,11 @@
 
   {#if !connected}
   <div class="text-center">
+    {#if configDone}
+      <div class="text-2xl mb-3">Config written ✔ Device restarted</div>
+    {:else if fwDone}
+      <div class="text-2xl mb-3">Firmware written ✔ Device restarted</div>
+    {/if}
     <button class="btn" onclick={connect}>Connect</button>
     <div class="text-sm mt-2 opacity-70">{portInfo}</div>
   </div>