From 6c93ba4b1a718f818d9f4247005dc051fb1d3c3d Mon Sep 17 00:00:00 2001
From: Itay Sharoni <110981018+Itay-Sharoni@users.noreply.github.com>
Date: Thu, 3 Sep 2026 23:05:09 +0300
Subject: [PATCH] Gate ELRS modules below the 3.5.4 minimum

---
 src/SCRIPTS/CRSFSimulator/csrfsimulator.lua |  7 +++++--
 src/SCRIPTS/ELRS/crsf_session.lua           | 20 ++++++++++++++++++++
 src/SCRIPTS/TOOLS/ExpressLRS/main.lua       |  4 ++--
 src/SCRIPTS/TOOLS/ExpressLRS/ui/lcd.lua     |  7 ++++---
 src/SCRIPTS/TOOLS/ExpressLRS/ui/lvgl.lua    |  6 ++++--
 5 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/src/SCRIPTS/CRSFSimulator/csrfsimulator.lua b/src/SCRIPTS/CRSFSimulator/csrfsimulator.lua
index b15d030..7cd9583 100644
--- a/src/SCRIPTS/CRSFSimulator/csrfsimulator.lua
+++ b/src/SCRIPTS/CRSFSimulator/csrfsimulator.lua
@@ -54,6 +54,9 @@ local shim = loadScript("/SCRIPTS/CRSFSimulator/shim.lua")()
 --                    in minimized widgets, full-screen subtitle updates).
 --   "no_module"      No CRSF module found at all. Triggers the "No Module
 --                    Found" error dialog immediately.
+--   "old_firmware"   TX reports ExpressLRS 3.4.2, below the tool's 3.5.4
+--                    minimum. Triggers the unsupported-firmware screen
+--                    instead of the parameter list.
 --   "critical_error" TX + RX connected but the module reports a critical
 --                    error (baud rate too low). Exercises the warning screen
 --                    and the suppress-critical-errors write (field id 0x2E),
@@ -498,7 +501,7 @@ local txDevice = {
   name = "TX16S MK3",
   serialNo = CRSF.ELRS_SERIAL_ID,
   hwVer = 0,
-  swVer = 0x00030500, -- 3.5.0
+  swVer = config.scenario == "old_firmware" and 0x00030402 or 0x00040100, -- 3.4.2 / 4.1.0
   fieldCount = 25, -- total parameter count
   params = {
     {
@@ -722,7 +725,7 @@ local rxDevice = {
   name = "Bob 2400RX",
   serialNo = CRSF.ELRS_SERIAL_ID,
   hwVer = 0,
-  swVer = 0x00030500, -- 3.5.0
+  swVer = 0x00040100, -- 4.1.0
   fieldCount = 25, -- total parameter count
   params = {
     {
diff --git a/src/SCRIPTS/ELRS/crsf_session.lua b/src/SCRIPTS/ELRS/crsf_session.lua
index f0aded8..0ead874 100644
--- a/src/SCRIPTS/ELRS/crsf_session.lua
+++ b/src/SCRIPTS/ELRS/crsf_session.lua
@@ -67,6 +67,7 @@ function CRSFSession.new(opts)
     -- Read-and-clear flags for the app
     fieldHiddenChanged = nil,
     v1Detected = nil,
+    unsupportedElrs = nil, -- version string of an ELRS TX too old to browse
     -- Reassembly state (crsf_params.lua manages it; rx.chunk is readable)
     rx = { chunk = 0, expect = -1 },
 
@@ -185,6 +186,22 @@ function CRSFSession:_onFrame(command, data)
   end
 end
 
+-- The one home of the minimum ExpressLRS firmware: 3.5.4. Older modules
+-- predate the spec-compliant folders of ExpressLRS #3123 and cannot be
+-- browsed, so the session latches .unsupportedElrs instead of loading
+-- garbage (Lua-Scripts #11).
+local function elrsVersionOk(info)
+  if info.vMaj >= 4 then
+    return true
+  elseif info.vMaj == 3 and info.vMin > 5 then
+    return true
+  elseif info.vMaj == 3 and info.vMin == 5 and info.vRev >= 4 then
+    return true
+  end
+
+  return false
+end
+
 function CRSFSession:_onDeviceInfo(data)
   local info = crsf:decodeDeviceInfo(data)
   if not info then
@@ -199,6 +216,9 @@ function CRSFSession:_onDeviceInfo(data)
   device.name = info.name
   device.fieldCount = info.fieldCount
   device.isElrs = info.isElrs
+  if device.isElrs and device.id == crsf.CONST.ADDRESS_TX and not elrsVersionOk(info) then
+    self.unsupportedElrs = info.vMaj .. "." .. info.vMin .. "." .. info.vRev
+  end
   if self._onDeviceUpdate then
     self._onDeviceUpdate(device, isNew)
   end
diff --git a/src/SCRIPTS/TOOLS/ExpressLRS/main.lua b/src/SCRIPTS/TOOLS/ExpressLRS/main.lua
index 2e6cd19..27c41ce 100644
--- a/src/SCRIPTS/TOOLS/ExpressLRS/main.lua
+++ b/src/SCRIPTS/TOOLS/ExpressLRS/main.lua
@@ -178,8 +178,8 @@ local function run(event, touchState)
   session:drain()
   session:tick()
 
-  if session.v1Detected then
-    UI.handleUnsupported()
+  if session.v1Detected or session.unsupportedElrs then
+    UI.handleUnsupported(session.unsupportedElrs)
     return 0
   end
 
diff --git a/src/SCRIPTS/TOOLS/ExpressLRS/ui/lcd.lua b/src/SCRIPTS/TOOLS/ExpressLRS/ui/lcd.lua
index cbc0603..1f74cb4 100644
--- a/src/SCRIPTS/TOOLS/ExpressLRS/ui/lcd.lua
+++ b/src/SCRIPTS/TOOLS/ExpressLRS/ui/lcd.lua
@@ -135,10 +135,11 @@ end
 -- Interface: handleUnsupported
 -- ============================================================================
 
-function UI.handleUnsupported()
+-- oldVersion set means an ELRS module below the minimum; nil means 1.x.
+function UI.handleUnsupported(oldVersion)
   drawAlert("Unsupported Firmware", {
-    "ELRS 1.x firmware detected.",
-    "Please update to 3.x.",
+    oldVersion and ("ELRS " .. oldVersion .. " detected.") or "ELRS 1.x firmware detected.",
+    oldVersion and "Requires 3.5.4 or later." or "Please update to 3.x.",
   })
 end
 
diff --git a/src/SCRIPTS/TOOLS/ExpressLRS/ui/lvgl.lua b/src/SCRIPTS/TOOLS/ExpressLRS/ui/lvgl.lua
index ccbb7d0..3fd0720 100644
--- a/src/SCRIPTS/TOOLS/ExpressLRS/ui/lvgl.lua
+++ b/src/SCRIPTS/TOOLS/ExpressLRS/ui/lvgl.lua
@@ -367,11 +367,13 @@ end
 -- Interface: handleUnsupported
 -- ============================================================================
 
-function UI.handleUnsupported()
+-- oldVersion set means an ELRS module below the minimum; nil means 1.x.
+function UI.handleUnsupported(oldVersion)
   if not UI.uiBuilt then
     Dialogs.showMessage({
       title = "Unsupported Firmware",
-      message = "ELRS 1.x firmware detected. Please update to 3.x.",
+      message = oldVersion and ("ELRS " .. oldVersion .. " detected. Requires 3.5.4 or later.")
+        or "ELRS 1.x firmware detected. Please update to 3.x.",
     })
     UI.uiBuilt = true
   end