ADSP-BF50x Blackfin Processor Hardware Reference
19-27
SPORT Controller
RFS
pulse (when the frame sync is internally generated). This enables a
frame sync to initiate periodic transfers. The counting of serial clock
cycles applies to either internally or externally generated serial clocks.
The formula for the number of cycles between frame sync pulses is:
# of transmit serial clocks between frame sync assertions =
TFSDIV
+ 1
# of receive serial clocks between frame sync assertions =
RFSDIV
+ 1
Use the following equations to determine the correct value of
TFSDIV
or
RFSDIV
, given the serial clock frequency and desired frame sync frequency:
SPORT TFS frequency = (
TSCLK
frequency)/(
SPORT_TFSDIV
+ 1)
SPORT RFS frequency = (
RSCLK
frequency)/(
SPORT_RFSDIV
+ 1)
The frame sync would thus be continuously active (for transmit if
TFSDIV
= 0 or for receive if
RFSDIV
= 0). However, the value of
TFSDIV
(or
RFSDIV
) should not be less than the serial word length minus 1 (the value
of the
SLEN
field in
SPORT_TCR2
or
SPORT_RCR2
). A smaller value could
cause an external device to abort the current operation or have other
unpredictable results. If a SPORT is not being used, the
TFSDIV
(or
RFSDIV
) divisor can be used as a counter for dividing an external clock or
for generating a periodic pulse or periodic interrupt. The SPORT must be
enabled for this mode of operation to work.
Maximum Clock Rate Restrictions
Externally generated late transmit frame syncs also experience a delay from
arrival to data output, and this can limit the maximum serial clock speed.
See
ADSP-BF504, ADSP-BF504F, ADSP-BF506F Embedded Processor
Data Sheet
for exact timing specifications.
Содержание EZ-KIT Lite ADSP-BF506F
Страница 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 132: ...Unique Information for the ADSP BF50x Processor 4 22 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 342: ...Unique Information for the ADSP BF50x Processor 7 106 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 484: ...Unique Information for the ADSP BF50x Processor 10 60 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 493: ...ADSP BF50x Blackfin Processor Hardware Reference 11 9 Core Timer Unique Information for the ADSP BF50x Processor None ...
Страница 494: ...Unique Information for the ADSP BF50x Processor 11 10 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 506: ...Unique Information for the ADSP BF50x Processor 12 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 544: ...Unique Information for the ADSP BF50x Processor 13 38 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 712: ...Unique Information for the ADSP BF50x Processor 16 62 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 972: ...Unique Information for the ADSP BF50x Processor 20 38 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...