MAX5423 MAXIM [Maxim Integrated Products], MAX5423 Datasheet - Page 6

• Manufacturer Part Number: MAX5423
• Description: Evaluation Kit
• Manufacturer: MAXIM [Maxim Integrated Products]

MAX5422 Evaluation Kit
The Data Sent indicator in the Interface group box dis-
plays the last data sent from the master (software) to
the MAX5422. The Data Sent indicator displays the last
data sent for the write to VREG (0x00) command and
the write to NVREG (0x10) command. Since the
VREGxNVREG (0x20) and the NVREGxVREG (0x30)
commands do not send any new data to the MAX5422,
the Data Sent indicator is hidden when these two com-
mands are executed.
The MAX5422 IC uses an 8-bit (MSBs, D7–D0) data
byte to set the wiper position. Refer to the MAX5422/
MAX5423/MAX5424 IC data sheet for additional
information.
Press the Tab key to select each GUI control. The
selected control is indicated by a dotted outline. Using
Shift + Tab moves the selection to the previously select-
ed control. Buttons respond to the keyboard’s space
bar and some controls respond to the keyboard’s up
and down arrow keys. Activate the program’s menu bar
by pressing the F10 key and then press the letter of the
desired menu item. Most menu items have one letter
underlined, indicating their shortcut key.
When a number is entered into the volatile or non-
volatile text boxes, it can be sent to the device by
pressing the Enter key. It is also sent when Tab or Shift
+ Tab is pressed.
There are two methods for communicating with the
MAX5422 EV kit, through the normal user-interface
panel (Figure 1) or through the SPI commands avail-
able by selecting the 3-Wire Interface (Figure 3) utility
from the main program’s Options | Interface
(Advanced Users) main menu. A window is displayed
that allows SPI send/receive data operations.
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Simple SPI Commands
Keyboard Navigation
Data Sent Indicator
The Connection group box allows the user to define the
hardware connections of the interface. For the
MAX5422 EV kit, select K10 from the Clock (SCK)
(SCLK) drop-down list, K12 from the Data from master
to slave (MOSI) (DIN) drop-down list, K11 from the
Data from slave to master (MISO) (DOUT) drop-down
list, K9 from the Chip-select (CS) for data framing
drop-down list, and uncheck the Use standard connec-
tions for high-speed SPI checkbox (see Figure 3).
The Configuration group box allows the user to config-
ure the logic level and data rate. For the MAX5422 EV
kit, check the Send & Receive MSB first and the
CPOL=1 (clock idle high) checkboxes (see Figure 3).
The Send and Receive Data group box allows the user
to send and receive data to and from the MAX5422.
The Data bytes to be written edit box is data to be
sent from the master (microcontroller) to the device
(MAX5422). Eight-bit hexadecimal numbers should be
comma delimited. Press the Send Now button to trans-
mit the data from the master to the device. Data
appearing in the Data bytes received edit box is data
read from the device. The Data bytes received edit
box in the MAX5422 EV kit software always shows a
default value of 0xFF since the MAX5422 does not
send data back to the master.
Note: The SPI dialog boxes accept numeric data in
hexadecimal format. Hexadecimal numbers must be
prefixed by $ or 0x. See Figure 3 for an example of
this tool. Figure 3 shows a simple SPI write-byte oper-
ation using the included 3-wire interface diagnostics
tool. In this example, the software is sending a com-
mand 0x00 (write to volatile memory), and a data
0x7F. The data sequence sets the MAX5422 wiper
position to 128.