TLC34076 Datasheet, PDF (16/68 Pages) Texas Instruments – Video Interface Palette

1.5 Terminal Functions (TLC34076C and TLC34076M) (Continued)
TERMINAL
I/O
NAME
NO.{
NO.}
DESCRIPTION
VGA0 – VGA7 65 – 72
M6, L6, M5,
L5, M4, L4,
M3, M2
I VGA pass-through bus. The VGAn bus can be selected as the pixel
bus for the VGA pass-through mode. It does not allow for any
multiplexing.
VREF
53
M12
Voltage reference for DACs. An internal voltage reference of
nominally 1.235 V is supplied. A 0.1-µF ceramic capacitor between
VREF and GND is recommended for noise filtering using either the
internal or an external reference voltage. The internal reference
voltage can be overridden by an externally supplied voltage. The
typical connection is shown in Appendix B.
WR
30
A11
I Write strobe input. A low on WR initiates a write to the TLC34076
register map. Write transfers are asynchronous. The data written to
the register map is latched on the rising edge of WR (see
Figure 3–1).
8/6
64
L7
I DAC resolution selection. The 8/6 terminal selects the data bus
width (8 or 6 bits) for the DACs and is provided to maintain
compatibility with the INMOS IMSG176/8 color palette. When this
terminal is high, 8-bit bus transfers are used, with D7 being the MSB
and D0 the LSB. For 6-bit bus operation, while the color palette still
has the 8-bit information, D5 shifts to the bit 7 position, D0 shifts to
the bit 2 position, and the two LSBs are filled with zeros at the output
MUX to the DAC. When read in the 6-bit mode, the palette holding
register zeros the two MSBs.
{ Terminal numbers shown are for the FN package.
} Terminal numbers shown are for the GA package.
NOTES: 1. Although leaving unused terminals floating does not adversely affect device operation, tying unused
terminals to ground lowers power consumption, thus is recommended.
2. All digital inputs and outputs are TTL compatible, unless otherwise noted.
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