FreeRTOS+UDP was removed from the FreeRTOS kernel download from
FreeRTOS V10.1.0. See the FreeRTOS+TCP stack, which can be
configured for UDP only use, as an alternative.
xNetworkBufferDescriptor_t *pxNetworkBufferGet( size_t xRequestedSizeBytes,
TickType_t xBlockTimeTicks );
Obtains from the IP stack a free
network buffer descriptor
that (optionally) references a free Ethernet buffer.
pxNetworkBufferGet() must not be called from an interrupt service routine (ISR).
The size of the Ethernet buffer to obtain and reference
from the returned network buffer descriptor. The size
is specified in bytes.
If xRequestedSizeBytes is zero then the returned network
buffer descriptor will not reference an Ethernet buffer
(the reference is set to NULL).
If a network buffer is not available then the calling task
will be held in the Blocked state (so other tasks can
execute) until either a network buffer becomes available
or the specified block time expires.
The block time is specified in RTOS ticks. To convert
a time specified in milliseconds to a time specified in
RTOS ticks divide the time specified in milliseconds by
Successful calls return a pointer to the obtained network buffer
descriptor. Unsuccessful calls return NULL.
Examples are provided on the
Porting FreeRTOS to a Different Microcontroller
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