Figure 4-2. DACA Tab With NCO settings
The GUI comes with two default NCO setting configuration files. One called
"EXT_CLK_6400M_NCOA_1_4_100_400MHz.cfg" which sets the first 4 DAC NCOs to 100 MHz, 200 MHz,
300 MHz, and 400 MHz. With a 6.4-GHz external clock provided to the EVM and this configuration file loaded,
the user can select any one of these four NCOs to be sent to the CHA output. The GUI box labeled SPI NCOA
bank select determines which NCO is used.
The second configuration file called "LMK_100M_LMX_6400M_NCOA_1_4_100_400MHz" loads the same
parameters but is used with the EVM setup in onboard clock mode.
The digital input data is not used in the NCO mode. The TSW14DL3200EVM is not required.
To enter the desired NCO frequency and phase settings, the user must first enter the DAC sample rate in the
box labeled as F_DACA(MHz). The value entered is in megahertz.
The user then selects which NCOs they plan on using and enter the NCO frequency in megahertz in the first
column. After entering the value, clicking anywhere in the GUI or pressing enter on the keyboard will load the
required registers and update the second column with the actual register setting used to generate this frequency.
The same instructions apply for setting the NCO phase. The value to be entered for phase is in radians. The
valid entries are from –3.1416 to 3.1416. The equation for this setting can be found in the device data sheet.
Other Modes of Operation
SBAU374 – MAY 2021
DAC12DL3200 Evaluation Module
19
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