PI2Media 502HTA
Hardware Reference Manual – P3 - 8/31/2017
PAGE 7
4
ON-BOARD FUNCTIONS
4.1
OVERVIEW
The 502HTA interfaces to the RPi via the 40-Pin GPIO Connector. This section
describes in detail the functionality located on the 502HTA.
4.2
PCM5102A 24-BIT 192KHZ DAC
At the core of the 502HTA is the Texas Instruments PCM5102A 24-Bit 192Khz DAC.
This device interfaces to the Raspberry Pi via the I2S. The signals used to interface with
the PCM5102A are shown in the following table.
PCM5102A
Signal
RPi
Signal
Description
MCLK
-
Grounded at PCM5102A
BCLK
BCLK
I2S Bit Clock from Pi
LRCLK
LRCLK
I2S Word Clock from Pi
SDIN
SDOUT
I2S Serial Audio Data from Pi
DEMP
GPIO13
Pulled High to Enable De-Emphasis, Drive Low
to Disable
FILT
GPIO6
Pulled High to Enable Digital Filter, Drive Low to
Disable
*MUTE
GPIO5
Pulled Low to Mute, Drive High to Enable
Table 2 – RPi to PCM5102A Connections
4.2.1
PCM5102A 24-BIT 192KHZ DAC NOTES
1. The PCM5102A is not populated on the 502HTA-SA.
2. The 502HTA is designed for the Raspberry Pi to operate in master mode,
supplying the Bit Clock, Word Clock and Audio Data to the PCM5102A. In
this mode the PCM5102A derives its master clock from an internal PLL
using the Raspberry Pi Bit Clock (BCLK) as the source. The PCM5102A
automatically detects the incoming frequency of BCLK and adjust its PLL
accordingly.
3. The PCM5102A is Hardware controlled and thus has no direct SW visible
functionality. But, three GPIO’s (5, 6, and 13) are connected in order to
