Hi,
As you know, AHCLKX0 & AHCLKX2 are pinmuxed on the C6747 device, but the AC characteristics of McASP0 Timing Requirements says,
tc(AHCLKRX) min = 25ns
But, "McASP2 Timing Requirements" says,
tc(AHCLKRX) min = 15ns
I'm curious that, the reason why those are different. Or is it any typo of the specification ?
best regards,
Hirofumi Fujita
Fujita-san,
I think the data mentioned in the datasheet is correct because McASP2 on C6747 has DIT mode capability while McASP0/1 can only supports TDM or I2S modes. For DIT mode, the the internal bit clock needs to runs two times faster than the equivalent bit clock required for I2S or TDM mode, due to the need to generate Biphase Mark Encoded Data. Hence the higher clock rate on McASP2.
Regards,
Rahul
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In addition to what Rahul provided, talking to the McASP expert, from a chip physical design/placement perspective the McASP2 IP block is really closer to the actual IO pins/pads compared to McASP0 and 1 blocks, giving it the for McASP2 to run lot faster that the the other two.
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