ADV7150LS135 AD [Analog Devices], ADV7150LS135 Datasheet - Page 20

• Manufacturer Part Number: ADV7150LS135
• Description: CMOS 220 MHz True-Color Graphics Triple 10-Bit Video RAM-DAC
• Manufacturer: AD [Analog Devices]

ADV7150
Power-On Reset
On power-up of the ADV7150 executes a power-on reset opera-
tion. This initializes the pixel port such that the pixel sequence
ABCD starts at A. The Mode Register (MR17–MR10), Com-
mand Register 2 (CR27–CR20) and Command Register 3
(CR37–CR30) have all bits set to a Logic “1.” Command Regis-
ter 1 (CR17–CR10) has all bits set to a Logic “0.”
The output clocking signals are also set during this reset period.
The power-on reset is activated when V
5 V. This reset is active for 1 s. The ADV7150 should not be
accessed during this reset period. The pixel clock should be
applied at power-up.
MODE REGISTER MR1 (MR19–MR10)
The mode register is a 10-bit wide register. However for pro-
gramming purposes, it may be considered as an 8-bit wide regis-
ter (MR18 and MR19 are both reserved). It is denoted as
MR17–MR10 for simplification purposes.
The diagram shows the various operations under the control of
the mode register. This register can be read from as well written
to. In read mode, if MR18 and MR19 are read back, they are
both returned as zeros.
Mode Register (MR17–MR10) Bit Description
Reset Control (MR10)
This bit is used to reset the pixel port sampling sequence. This
ensures that the pixel sequence ABCD starts at A. It is reset by
writing a “1” followed by a “0” followed by a “1.” This bit must
be run through this cycle during the initialization sequence.
RAM-DAC Resolution Control (MR11)
When this is programmed with a “1,” the RAM is 30 bits deep
(10 bits each for red, green and blue) and each of the three
DACs is configured for 10-bit resolution. When MR11 is
PRGCKOUT = CLOCK/32
LOADOUT = CLOCK/4
* THESE BITS ARE READ-ONLY RESERVED BITS.
A READ CYCLE WILL RETURN ZEROS "00."
RESERVED*
MR19
MATCH BITS CONTROL
MR16
MR17
PALETTE SELECT
MR18
PS0
PS1
MR17
MR14
AA
OPERATIONAL MODE CONTROL
0
0
1
1
goes from 0 V to
MR13
MR16
Mode Register 1 (MR1) (MR19–MR10)
0
1
0
1
MR15
CALIBRATE
LOADIN
RESERVED
RESERVED
RESERVED
NORMAL OPERATION
MR15
–20–
MR14
REGISTER PROGRAMMING
The following section describes each register, including Address
Register, Mode Register and each of the nine Control Registers
in terms of its configuration.
Address Register (A7–A0)
As illustrated in the previous tables, the C0 and C1 control in-
puts, in conjunction with this address register specify which
control register, or color palette location is accessed by the
MPU port. The address register is 8-bits wide and can be read
from as well as written to. When writing to or reading from the
color palette on a sequential basis, only the start address needs
to be written. After a red, green and blue write sequence, the
address register is automatically incremented.
programmed with a “0,” the RAM is 24-bits deep (8 bits each
for red, green and blue) and the DACs are configured for 8-bit
resolution. The two LSBs of the 10-bit DACs are pulled down
to zero in 8-bit RAM-DAC mode.
MPU Databus Width (MR12)
This bit determines the width of the MPU port. It is configured
as either a 10-bit wide (D9–D0) or 8-bit wide (D7–D0) bus.
10-bit data can be written to the device when configured in
8-bit wide mode. The 8 MSBs are first written on D7–D0, then
the two LSBs are written over D1–D0. Bits D9–D8 are zeros in
8-bit mode.
Operational Mode Control (MR14–MR13)
When MR14 is “0” and MR13 is “1,” the part operates in
normal mode.
Calibrate LOADIN (MR15)
This bit automatically calibrates the onboard LOADIN/
LOADOUT synchronization circuit. A “0” to “1” transition
initiates calibration. This bit is set to “0” in normal operation.
See “Pipeline Delay and Calibration” section. This bit must be
run through this cycle during the initialization sequence.
MR12
MPU DATA BUS WIDTH
0
1
MR13
8-BIT (D7–D0)
10-BIT (D9–D0)
RESOLUTION CONTROL
MR11
0
1
MR12
RAM-DAC
8-BIT
10-BIT
MR11
MR10
RESET CONTROL
MR10
REV. A