Datasheet

MAX9880A Evaluation Kit
Evaluates: MAX9880A
20 _____________________________________________________________________________________
Figure 17. Line Input and Output Enable Blocks
Save/Load Settings
Register configurations can be saved/loaded by select-
ing the Save Settings CTRL+S or Load Settings
CTRL+O menu item from the File menu bar. The save
operation saves the state of the U1 device registers,
S/PDIF transceiver (U11) registers, and a few general-
purpose input-output (GPIO) settings to a configura-
tion file. The load operation configures the U1 and U11
device registers and sets/clears specific GPIO pins
based on the data and settings contained in the con-
figuration file.
A Configuration 1.ax27 file is included in the MAX9880A
software directory and contains the data and settings
that result from performing the procedure in the Quick
Start section. The default and recommended file exten-
sion is .ax27.
Advanced User Interface
The Advanced User Interface window can also be used
to communicate with the U1 and U11 devices. Use the
Tools | Interface (Advanced Users) F1 menu item to
open the interface window, which can be used for SPI
communication, I
2
C/SMBus™ communication, and to
control the MAXQ2000 GPIOs that the EV kit utilizes.
This window consists of four main tabs: Connection, Bit
Set/Clear, 2-wire Interface, and 3-wire Interface (see
Figure 18). The interface utility only accepts and outputs
hexadecimal number format.
Connect
The Connection tab is used to establish a connection
with the MAXQ2000 interface included on the EV kit.
Bit Set/Clear
The Bit Set/Clear tab provides control of the MAXQ2000’s
available GPIO pins. The only GPIO pins utilized by the
EV kit are listed in Table 12, along with their functionality.
2-Wire Interface
The 2-wire interface tab’s General commands tab
(Figure 19) allows general-purpose 2-wire commands to
be sent using the Command (SMBus Protocols, Raw
Block Read/Write, EEPROM Read/Write) drop-down
list and the Execute button. The read/write commands
to use with the U1 device are SMBusWriteByte and
SMBusReadByte. The SMBusWriteByte transmits the
device address, command, and 1 byte of data. The
SMBusReadByte transmits the device address, a com-
mand, and then retransmits the device address and
reads 1 byte of data.
The device address used by the commands is the
value displayed in the Target Device Address drop-
down list, which is generated by pressing the Hunt for
active listeners button. This button scans the entire
2-wire address space, reporting each address that is
acknowledged. For both a read and write operation,
the Command Byte is the register address. The data to
write to the target device should be entered in the Data
Out field and the data that is read is reported in the Data
In field. The SCL frequency can also be configured by
selecting the Low Level commands tab and using the
speed buttons and/or edit fields to set the operating
frequency.
SMBus is a trademark of Intel Corp.