Datasheet

Evaluates: MAX9257A/MAX9258A
15) Exercise different pixel clocks by selecting different
options in the Change PCLK_IN/HSYNC_IN/
VSYNC_IN group box. The selected pixel clock
should be in the range of the configured PRATE
range, and the following relationship formula must
be met:
Serial Word Length x Pixel Clock = Serial
Data Rate ≤ 840Mbps
It is preferred to select the pixel clock frequency
before the clock is enabled.
16) To select a different UART speed, change the cam-
era UART speed first and then go to the ECU
Control tab sheet to change ECU UART speed
accordingly. Ensure that t
STO
and t
ETO
values are
set correctly in order for the UART speed to work
properly. The MAX9258A REG07 FAST bit and
MAX9257A REG08 FAST bit should be configured
correctly before choosing a different UART speed.
17) Press the Disable PCLK_IN/HSYNC_IN/VSYNC_IN
button to disable the video clock inputs to the
MAX9257A. Check that the D1 green LED is turned
off (MAX9258A LOCK pin stays low) and that the
control channel is available indefinitely (MAX9258A
CCEN pin stays high).
18) During any step above, the user can navigate to the
Deserializer MAX9258A or Serializer MAX9257A
tab sheets and perform read or write operations
because INTEN is reset to 0 after every operation.
I
2
C Mode
If the camera uses an I
2
C interface, both the
MAX9257A and MAX9258A should be configured to
use the I
2
C interface. Because the on-board emulated
camera uses the default UART interface, the camera
must first be switched from the UART interface to an
I
2
C interface. Follow the steps below to evaluate the
SerDes link in base mode when the I
2
C interface is
enabled:
1) Start the program or press the Reset the EVKIT
button on the ECU Control tab sheet (Figure 3).
2) If MAX9257A REM is set to high (JU25 shunt is set
across pins 1-2), then press the ECU Wakes Up
MAX9257A button on the ECU Control tab sheet. If
MAX9257A REM is set to low (JU25 shunt is set
across pins 2-3), then skip this step.
3) Navigate to the Deserializer MAX9258A tab sheet
(Figure 4). Press the Read MAX9258A & 9257A
button to refresh the current register values on the
GUI.
4) Keep the four Write Both 9258A&9257A checkbox-
es checked.
5) Set t
CTO
on both the MAX9257A and MAX9258A to
64.
6) Navigate to the Camera Control tab sheet (Figure
6) and press the Exit UART Mode → Enter I
2
C
Mode button (this button is available only when
CTO is not equal to 0).
7) Follow the reminder message by moving the shunts
from JU26 and JU27 (pins 1-2) to pins 2-3. Press
the OK button.
8) Now the camera and the SerDes use an I
2
C inter-
face. Navigate to any tab sheet and exercise the
features of the SerDes.
9) The I
2
C interface on the emulated camera can oper-
ate at speeds up to 4.25MHz. This is the same as
the MAX9257A and MAX9258A. Before changing
the ECU UART baud rate, the bit rates of the
MAX9257A and MAX9258A must be configured
properly.
Detailed Description of Hardware
The MAX9257A/MAX9258A EV kit is a complete SerDes
pair evaluation system for the MAX9257A serializer and
MAX9258A deserializer. Check the schematic for
detailed EV kit hardware. The following is a brief
description of the EV kit design.
Deserializer Side
(Right Side of the EV Kit Board)
Figure 7a shows the schematic for the MAX9258A.
Figure 7b shows the schematic for the power supplies,
a clock generator, and a microcontroller that communi-
cates with the PC. The microcontroller, together with an
FPGA, emulates an ECU.
Figure 7c shows the FPGA, which implements a high-
speed UART interface for the emulated ECU.
Serializer Side
(Left Side of the EV Kit Board)
Figure 7d shows the schematic for the MAX9257A.
Figure 7e shows the schematic for the power supplies,
a clock generator, and a microcontroller that, together
with an FPGA, emulate a camera.
Figure 7f shows the FPGA, which implements a high-
speed UART and a high-speed I
2
C interface for the
emulated camera. The FPGA also generates PCLK_IN,
HSYNC_IN, and VSYNC_IN for the emulated camera.
MAX9257A/MAX9258A Evaluation Kit
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