Chipset is GL843.

unsupported/hp-scanjet-4850.html

@@ -32,13 +32,18 @@
     </p>
     <h2>Chipset</h2>
     <p>
-      GL841
+      GL843
     </p>
     <h2>Comments</h2>
     <p>
       These devices could be supported by the genesys backed later. Both
       scanners have the same USB id.
     </p>
+    <p>
+      It looks like a GL841 chipset to sane-find-scanner, but it's actually a
+      GL843. (It's viewable from outside when the carriage is not in the parking
+      position.)
+    </p>
     <h2>Output of /proc/bus/usb/devices or sane-find-scanner -v -v or lsusb -vv</h2>
     <pre>
 4850: