Themis NanoPAK, User Manual

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A-6
Themis Computer
NanoPAK
®
User Manual Version 1.0
A.2 Signal Descriptions
There are provisions for variations in the pinouts to allow for General Purpose Inputs
and Outputs to share pins with the serial port signals. This frees up pins that are
made available for systems which need SATA outputs.
Table A-2 lists signal descriptions for those signals which remain the same within
systems irrespective of SATA or NON-SATA capability. Table A-3 lists signal
descriptions for systems with SATA capability where GPIO and Serial port signals
must share pins to make available pins for SATA signals.
Table A-4 lists signal
descriptions for GPIO and Serial port signals for systems with no SATA capability
where these signals do not share pins.
Table A-2. Signal Descriptions
Signal Name Description In/O u t
VGA_RED
VGA_GRN
VGA_BLU
VGA_HSYNC
VGA_VSYNC
VGA_PWR
These are the analog video signals. The VGA power is protected
by a 0.75A fuse on the carrier. It can be set to either 3.3V or 5V thru
solder bead. The default factory setting is 5V.
Out
RED_Return
GRN_Return
BLU_Return
HV_Return
Video return path: All connected to DGND. In
SCLK
Serial clock line of one of the three I
2
C buses available on the car-
rier. These buses are:
- the DDC bus for the VGA monitor
- the SMBus
- the I
2
C bus where the carrier FRU is attached.
The choice between one of these I
2
C buses is done thru solder
beads / 0 ohm resistor.
The selected I
2
C bus is buffered on the SBC carrier by a
PCA9515A I
2
C buffer. The voltage level on this bus is 3.3V.The de-
fault setting is for DDC.
I/O
SDAT
Serial data line of one of the three I
2
C buses available on the car-
rier. See above
I/O