ESP32-P4 datasheet(78/93 Pages) ESPRESSIF

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4 Functional Description

– Valid signal output

– Configurable bus idle value

Pin Assignment

The pins for the parallel IO controller can be chosen from any GPIOs via the GPIO Matrix.

4.2.2.19 BitScrambler

The ESP32-P4 has an extensive amount of DMA-capable peripherals. These can move data from memory to

an external device, and vice versa, without any interference from the CPU. This only works if the external

device needs or emits the data in question in the same format as the software expects it: if not, the CPU

needs to rewrite the format of the data. Examples include a need to swap bytes, reverse bytes, and shift the

data left or right.

Since bitwise operations can be relatively CPU-intensive and DMA is designed specifically to offload such

work from the CPU, ESP32-P4 integrates two dedicated peripherals called BitScramblers. These modules are

designed to transform data formats during transfers between memory and peripherals. One BitScrambler

handles memory-to-peripheral (or memory-to-memory) transfers, while the other is dedicated to

peripheral-to-memory transfers. While BitScramblers can handle the bitwise operations mentioned earlier, they

are in fact flexible, programmable state machines capable of performing more advanced transformations as

well.

Feature List

• Two BitScramblers, one for RX (peripheral-to-memory), one for TX (memory-to-peripheral)

• Support for memory-to-memory transfers

• Processing up to 32 bits per DMA clock period

• Data path controlled by a BitScrambler program stored in instruction memory

• Input registers able to read 0, 8, 16, or 32 bits per clock cycle

• Output registers:

– Able to write 0, 8, 16, or 32 bits per clock cycle

– Data sources for output register bits: 64 bits of input data, two counters, LUT RAM data, data output

of last cycle, comparators

– With some restrictions, each of the 32 output register bits can come from any bit on the data

sources

• An 8 x 257-bit instruction memory for storing eight instructions, controlling control flow, and the data path

• 2048 bytes of lookup table (LUT) memory, configurable as various word widths

Pin Assignment

The BitScrambler does not directly interact with IOs, so it has no pins assigned.

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ESP32-P4 Series Datasheet v0.5

ESP32-P4 Datasheet(PDF) 78 Page - ESPRESSIF SYSTEMS (SHANGHAI) CO., LTD.