User manual

4D SYSTEMS Armadillo-43(T) – Linux based Computer Display Module
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Armadillo-43(T) – Linux based Computer Display Module
Connecting J2 between pins 1 and 2 will allow the on board Audio Amplifier to be enabled and any audio that
is generated on the PGIO41 PWM signal (PWM1) will be amplified and played on the on-board speaker.
Connecting J2 between pins 2 and 3 will allow the GPIO34 pin to control the on Board Audio Amplifier’s
shutdown pin. This will allow a User to write a script or piece of software to enable or disable the on board
audio amplifier as required. This can be useful for many reasons, such as power saving, muting the audio, or for
using the PWM signal for another reason – such as motor control. If the on board Audio Amplifier is disabled
the PWM signal can be utilised by the User for other applications, other than Audio.
Removing the jumper entirely (or placing it over 1 pin only for safe storage) will force the on board Amplifier to
disable. This can be useful for many reasons, as per connecting between pins 2 and 3, however with the added
benefit that GPIO34 is also freed up to be used as a GPIO for other purposes. This can be helpful if you wish to
use the PWM1 signal for something other than Audio, and also require the GPIO34 signal for something other
than Audio Enable.
The JTAG header is used in the factory to program the bootloader into the BCM2835 SoC. It can also be used to
connect to a compatible JTAG debugger, however should only be utilised by Advanced users who know what
they are doing. This header makes for good mechanical support when adding a Daughter Board onto the
Armadillo-43T, if nothing else.
Currently there is no information available that can be provided in order to utilise this JTAG header, such as
which JTAG debugger can be utilised by a User or what software is required.
NOTE: Do not electrically connect anything to this header unless you know what you are doing.
J2 Jumper Header
Pin
Symbol
Description
1
+3.3V
Pull Up to 3.3V
2
SHDN
Shutdown pin of the on board Audio Amplifier
3
GPIO34
GPIO34 Connection, to allow GPIO control of the on board Amplifier Audio Enable
JTAG Header
Pin
Symbol
Description
1
GND
Ground Pin, System Ground
2
TCK
Test Clock Signal
3
GND
Ground Pin, System Ground
4
TMD / TMS
Test Mode Select Signal
5
GND
Ground Pin, System Ground
6
TDO
Test Data Out Signal
7
GND
Ground Pin, System Ground
8
TDI
Test Data In Signal
9
GND
Ground Pin, System Ground
10
TRST_N
Test Reset Signal