TM1100 Preliminary Data Book
Philips Semiconductors
6-2
PRELIMINARY INFORMATION
File: vin.fm5, modified 7/24/99
6.1.2
Diagnostic Mode
The Video-In logic can be set to operate in diagnostic
mode, which connects the inputs of VI to the outputs of
Video Out. This mode provides boot diagnostics with the
ability to verify major operational aspects of the chip be-
fore handing control to an operating system.
Diagnostic mode is entered by writing a control word with
a ‘1’ in the DIAGMODE bit position to the VI_CTL register
a clock before starting DIAGMODE. After a Video-In soft-
ware reset, the DIAGMODE bit has to be set back to ‘1’.
In diagnostic mode, the Video In signals are exactly as
shown in
Figure 6-2, except that the inputs come from
the on-chip Video Out unit. Note that the inputs are truly
taken from the TM1100 Video-Out external pins, i.e. if an
external (board level) source is driving Video Out pins,
diagnostic mode is not capable of testing Video-Out.
Note that the diagnostic mode only controls an input mul-
tiplexer. VI can be programmed and operated in all usual
modes. The
raw modes are particularly attractive for di-
agnostics purposes, since they allow VI to operate al-
most as an on-chip logic analyzer.
6.1.3
Power Down
The Video In logic participates in global TM1100 chip
power down, unless the SLEEPLESS bit in the VI_CTL
register is asserted.
6.1.4
Hardware and Software Reset
Video In is reset by a TM1100 hardware reset (pin
TRI_RESET#) or by a Video In software reset. The latter
is accomplished by writing a control word of 0x00080000
to the VI_CTL register. After a software reset, allow for 5
video clock cycles delay before enabling Video In cap-
ture. Upon hardware or software reset, the VI_CTL,
VI_STATUS, and VI_CLOCK registers are set to all ze-
ros. The state of the other registers after RESET is unde-
fined. Note that the Video-In clock has to be present
while applying the software reset.
Table 6-2. Video In Interface Pins
VI_CLK
I/O-5
If congured as input (power up
default): A positive transition on this
incoming video clock pin samples
all other VI_DATA input signals
below if VI_DVALID is HIGH. If
VI_DVALID is LOW, VI_DATA is
ignored. Clock and data rates of up
to 54 MHz are supported.
If congured as output: Program-
mable output clock to drive an
external video A/D converter. Can
be programmed to emit integral
dividers of DSPCPU_CLK.
See section
6.2 for clock program-
ming details.
VI_DVALID
IN-5
VI_DVALID indicates that valid data is
present on the VI_DATA lines. If HIGH,
VI_DATA will be accepted on the next
VI_CLK positive edge. If LOW, no
VI_DATA will be sampled.
VI_DATA[7:0]
IN-5
CCIR656 style YUV 4:2:2 data from a
digital camera, or general purpose
high speed data input pins. Sampled
on positive transitions of VI_CLK if
VI_DVALID HIGH.
VI_DATA[9:8]
IN-5
Extension high speed data input bits to
allow use of 10 bit video A/D convert-
ers in raw10 modes. VI_DATA[8]
serves as START and VI_DATA[9] as
END message input in message pass-
ing mode.Sampled on positive transi-
tions of VI_CLK if VI_DVALID HIGH.
DATA[7:0]
CLOCK
SDA, SCL
GND
Cable
Connector
VI_DATA[7:0]
VI_DVALID
VI_CLK
VSS
SDA, SCL
TM1100
logic ‘1’
VI_DATA[9:8]
GND
Termination &
Receivers
I2C bus
2
Figure 6-1. Video In connected to an 8-bit CCIR656 digital camera.