Description of Operation
16-8
ADSP-BF50x Blackfin Processor Hardware Reference
Bus Arbitration
The TWI controller initiates a master mode transmission (
MEN
) only when
the bus is idle. If the bus is idle and two masters initiate a transfer, arbitra-
tion for the bus begins. This is shown in
Figure 16-5
.
The TWI controller monitors the serial data bus (SDA) while
SCL
is high
and if SDA is determined to be an active logic 0 level while the TWI con-
troller’s data is a logic 1 level, the TWI controller has lost arbitration and
ends generation of clock and data. Note arbitration is not performed only
at serial clock edges, but also during the entire time
SCL
is high.
Start and Stop Conditions
Start and stop conditions involve serial data transitions while the serial
clock is a logic 1 level. The TWI controller generates and recognizes these
transitions. Typically start and stop conditions occur at the beginning and
at the conclusion of a transmission with the exception repeated start
“combined” transfers, as shown in
Figure 16-6
.
Figure 16-5. TWI Bus Arbitration
START
SCL (BUS)
TWI CONTROLLER
DATA
SECOND MASTER
DATA
SDA (BUS)
ARBITRATION
LOST
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 ...