Description of Operation
12-22
ADSP-BF537 Blackfin Processor Hardware Reference
increments of 8; the default value of 0 corresponds to a minimum active
window size of 8 channels. To calculate the active window size from the
WSIZE
register, use this equation:
Number of words in active window = 8 x (WSIZE + 1)
Since the DMA buffer size is always fixed, it is possible to define a smaller
window size (for example, 32 words), resulting in a smaller DMA buffer
size (in this example, 32 words instead of 128 words) to save DMA band-
width. The window size cannot be changed while the SPORT is enabled.
Multichannel select bits that are enabled but fall outside the window
selected are ignored.
Window Offset
The window offset (
WOFF[9:0]
) specifies where in the 1024-channel range
to place the start of the active window. A value of 0 specifies no offset and
896 is the largest value that permits using all 128 channels. As an example,
a program could define an active window with a window size of 8
(
WSIZE = 0
) and an offset of 93 (
WOFF = 93
). This 8-channel window
would reside in the range from 93 to 100. Neither the window offset nor
the window size can be changed while the SPORT is enabled.
If the combination of the window size and the window offset would place
any portion of the window outside of the range of the channel counter,
none of the out-of-range channels in the frame are enabled.
Other Multichannel Fields in SPORTx_MCMC2
The
FSDR
bit in the
SPORTx_MCMC2
register changes the timing relationship
between the frame sync and the clock received. This change enables the
SPORT to comply with the H.100 protocol.
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...