docs: Note some BL-Touch clones do not support touch_mode in BLTouch.md

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 16 insertions, 4 deletions

diff --git a/docs/BLTouch.md b/docs/BLTouch.md
index e7b2f9b5..4445a6a5 100644
--- a/docs/BLTouch.md
+++ b/docs/BLTouch.md
@@ -64,9 +64,10 @@ run `BLTOUCH_DEBUG COMMAND=touch_mode`, run `QUERY_PROBE`, and verify
 that command reports "probe: open". Then while gently pushing the pin
 up slightly with the nail of your finger run `QUERY_PROBE` again.
 Verify the command reports "probe: TRIGGERED". If either query does
-not report the correct message then check your wiring and
-configuration again. At the completion of this test run `BLTOUCH_DEBUG
-COMMAND=pin_up` and verify that the pin moves up.
+not report the correct message then it usually indicates an incorrect
+wiring or configuration (though some [clones](#bl-touch-clones) may
+require special handling). At the completion of this test run
+`BLTOUCH_DEBUG COMMAND=pin_up` and verify that the pin moves up.
 
 After completing the BL-Touch control pin and sensor pin tests, it is
 now time to test probing, but with a twist. Instead of letting the
@@ -106,7 +107,8 @@ commands to achieve this.
 ## BL-Touch "clones"
 
 Many BL-Touch "clone" devices work correctly with Klipper using the
-default configuration. However, some "clone" devices may require
+default configuration. However, some "clone" devices may not support
+the `QUERY_PROBE` command and some "clone" devices may require
 configuration of `pin_up_reports_not_triggered` or
 `pin_up_touch_mode_reports_triggered`.
 
@@ -116,6 +118,16 @@ these directions. Do not configure either of these to False on a
 genuine BL-Touch. Incorrectly setting these to False can increase
 probing time and can increase the risk of damaging the printer.
 
+Some "clone" devices do not support `touch_mode` and as a result the
+`QUERY_PROBE` command does not work. Despite this, it may still be
+possible to perform probing and homing with these devices. On these
+devices the `QUERY_PROBE` command during the
+[initial tests](#initial-tests) will not succeed, however the
+subsequent `G28` (or `PROBE`) test does succeed. It may be possible to
+use these "clone" devices with Klipper if one does not utilize the
+`QUERY_PROBE` command and one does not enable the
+`probe_with_touch_mode` feature.
+
 Some "clone" devices are unable to perform Klipper's internal sensor
 verification test. On these devices, attempts to home or probe can
 result in Klipper reporting a "BLTouch failed to verify sensor state"