Description of Operation
9-12
ADSP-BF50x Blackfin Processor Hardware Reference
Performance/Throughput
The
PFx
,
PGx
, and
PHx
pins are synchronized to the system clock (
SCLK
).
When configured as outputs, the GPIOs can transition once every system
clock cycle.
When configured as inputs, the overall system design should take into
account the potential latency between the core and system clocks. Changes
in the state of port pins have a latency of 3
SCLK
cycles before being detect-
able by the processor. When configured for level-sensitive interrupt
generation, there is a minimum latency of 4
SCLK
cycles between the time
the signal is asserted on the pin and the time that program flow is inter-
rupted. When configured for edge-sensitive interrupt generation, an
additional
SCLK
cycle of latency is introduced, giving a total latency of 5
SCLK
cycles between the time the edge is asserted and the time that the
core program flow is interrupted.
Description of Operation
The operation of the general-purpose ports is described in the following
sections.
Operation
The GPIO pins on port F, port G, and port H can be controlled individu-
ally by the function enable registers (
PORTx_FER
). With a control bit in
these registers cleared, the peripheral function is fully decoupled from the
pin. It functions as a GPIO pin only. To drive the pin in GPIO output
mode, set the respective direction bit in the
PORTxIO_DIR
register. To
make the pin a digital input or interrupt input, enable its input driver in
the
PORTxIO_INEN
register.
Summary of Contents for EZ-KIT Lite ADSP-BF506F
Page 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Page 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...