W681307 Datasheet, PDF (57/160 Pages) Winbond – USB1.1 CODEC Microprocessor Control Unit with 32KB Mask ROM and 4KB RAM

W681307
10.3
PCM Serial Interface
： The PCM Serial Interface
• Formats parallel PCM data to/from the Speech Processor for use by external devices
• PCM serial interface supports to convert serial pcm data of external devices to parallel pcm data of Speech Processor. PCM
highway supports 4 external devices by 4 slots pcm channels (B1 ~ B4). The internal USB ISO endpoint and the 4^th slot of PCM
highway are shared with the same PCM channel (B4). When the USB_EN bit is set to high, the internal USB ISO endpoint will
be automatically connected to the PCM channel (B4). All channels supports 8/16 bits pcm format, and IOM2 mode.
• PCM highway interface can support maste or slave modes with external devices.
• Implements a 4-bit general purpose IO port when the PCM Serial Interface function is not required
： Routing diagram as below Figure 10-2
Figure 10-2 W681307 Speech Flow Block Diagram
10.3.1
Use with Additional External Lines
The PCM serial interface block can route channels 1, 2 and 3 from the Speech Processor to PCM highway which can be used to interface
to external CODECs to provide connection to two external lines.
For this mode PcmIf enable =1 and Slave Mode =0.
PCM Serial Interface can generate a Long frame sync (for LongSync =1) or a Short frame sync (for LongSync=0).
Timing diagrams for short frame sync and long frame sync modes are given in section 9.7.
10.3.2
I/O Ports
For PCMH1_Dis =1, the Speech Interface is reset and PCM highway (pins name: PCM_OUT, PCM_IN, PCM_FSC, PCM_CLK) operate
as standard IO ports, controlled by SpeechIoD, SpeechIoIp and SpeechIoOp registers. An interrupt event will be generated if there is a
change in the value of any one of SpeechIoIp and the corresponding bit of SpeechIoMsk is set.
For PCMH1_Dis=0, the direction of PCM highway is always controlled by the PCM highway function setting. In the PCM master mode,
the PCM_OUT, PCM_FSC and PCM_CLK pins areoutput, the PCM_IN pin is input. In the PCM slave mode, the PCM_OUT pin is
output, the PCM_IN, PCM_FSC and PCM_CLK pins are output.
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Publication Release Date: May, 2007
Revision 1.3