T440 User’s manual Flat panel part © JED Micro Pty Ltd Page 8
Hisense RC5-code LCD TV via IR – Code AC
These panels are controlled via an IR emitter. It has the default address for a TV of “00”. A typical TV model is 24F33
and family. Unfortunately Hisense do not seem to know which IR codes apply to which model, and insist that this
model uses a completely different NEC-format IR protocol, which they supplied. We have verified the RC5 protocol
works with the 24F33 model.
An IR code is provided to access the “Source” menu and subsequent presses roll through available sources. Stopping on
the selected on automatically selects that one after about a 2 second delay. No OK button or arrow keys are needed for
selection. A Code 1 keyboard works well with this (Off, Source/On, Vol. Up, Vol Down). The LED associated with this
key blinks OFF momentarily as the function executes.
IR command codes:
SourceFunctionCode := $0038;
On a T440, Code 1 keyboard, the Volume Up and Volume Down keys send a burst of 5 signals, so the volume steps up
or down in groups of 5.
The red and green LEDs follow the current state of the projector. If the projector gets out of step with the controller (eg
by the projector being ON when the red OFF led is showing), pressing the ON button will get it back into step, and then
pressing OFF once will send the “POWER” IR message twice, with a 1-second separation, leaving both OFF.
Because there is no feedback serial path to the controller, OPT7 status read-back is not possible. (Freeze and mute are
not supported. Two-button-mute mode is not supported either.)
Wiring: The IR transmitting bug is wired to the IR output socket
J2 with the shield of the cable connected to the ground pin and
the centre conductor to the “+IR” pin. The signal is current
limited (24mA pulses), so no series resistors are needed in the
cable.
As the IR bug wire is only 2M long it will usually be extended,
and CAT5 cable is OK for this, but it must be via its own twisted
pair (colour plus colour-with-white). (We have successfully
tested this with 50M of CAT5E cable.)
If the CAT5 connector and cable is used runs from CAT5
connector J6, the IR signal runs
via a twisted pair of wires via this cable, but link L1 must be
moved from Tx (it’s position
in RS232 mode) to IR (as needed for IR mode).
T430: If using a T430, the keyboard has an ON/Source key and no Volume keys. The IR functions allow power On/Off
and source change only. Operation is the same as above.
If OPT4 is OFF, no source changes occur (for a V1 keyboard).
If OPT4 is ON, then a “source” command is sent with each press of the On / Source key. (V3 keyboard.)
(Note: the IR connector has to be requested at ordering time… it is not part of a normal T430 build.)
