I have an AD9957 Evaluation Board and want to experiment with the RAM. Are there any proven RAM test patterns available?
Two of the attached files are RAM test vectors:
File #1 is a QPSK modulation pattern consisting of 256 pseudorandom symbols oversampled by a factor of 4 and pulse shaped using a 45-tap digital raised cosine filter with an alpha (bandwidth) factor of 0.35.
File #2 is a quadrature dual-tone sinusoid that produces a single-sideband suppressed-carrier output containing two tones offset from the carrier by f1 and f2 as follows:
f1 = Fs/(4096*R)
Note that Fs is the internal system clock rate of the AD9957 and R is the CCI interpolation factor.
Both files contain 1024 samples formatted as 32-bit integers. Therefore, when loading these files via the QDUC RAM Control window of the Evaluation Board software, use the "RAW Decimal" selection (see the attached AD9957RAMScreenShot.jpg file). Also, be sure to load the RAM Address Step Rate register with a value of 1 (0x0001), otherwise the RAM will play the data back at the wrong rate.
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