I2S_V51; Sram - Samsung S5PC110 Manual

S5PC110_UM 1 AUDIO SUBSYSTEM

1.5.4 I2S_V51

The major difference between I2S V3.2 and I2S V5.1 lies in the presence of small AHB DMA. The previous
version of I2S did not allow the audio data to be played without external DMA. I2S V5.1 allows the audio data to
play with its own DMA. I2S DMA issues only 32-bit single read transaction.
I2S V5.1 comprises of an interrupt request signal to wake up ARM if S5PC110 is in the Idle and Deep-idle modes.
Interrupt request signal occurs if the pre-defined configuration of I2S DMA operations is complete. After CPU
wakes up, CPU prepares, generates, and saves the next audio data to be played in SRAM at audio subsystem.
Then CPU is powered off again to save power.
For more information, refer to the I2S_V51 User's Manual.

1.5.5 SRAM

The total memory size in audio subsystem is 214KB SRAM, out of which 64KB is reserved for IMEM, 96KB is
reserved for DMEM, 36KB is reserved for IBUF0 and IBUF1, and 18KB is reserved for OBUF0 and OBUF1. These
memories can be accessed by both internal and external modules in audio subsystem.
For more information on how to use this SRAM for low power music play, refer to Section 6, "Programming
Guide". If low power audio functionality is not needed, 214KB SRAM can be used as data reservoir.
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