MSC8144E Reference Manual, Rev. 3
19-32
Freescale
Semiconductor
TDM Interface
1.
Verify that the active (TACT) bit of the channel is clear.
2.
Write the initialization value to the channel locations in the transmit TDM local
memory.
The transmit local memory contains 1, 2, 4, 8, 16, or 32 buffers so that each buffer
contains 8 bytes per channel. The location of channel C in buffer B is the 8 bytes that start
at (256 / (TNB + 1)
×
B + C)
×
8. (See Section 19.2.3, TDM Data Structures, on page
19-13). Initializing the transmit TDM local memory prevents invalid data from being
transmitted out.
3.
Set the TDMxTCPRC[TACT] bit (C indicates the channel number).
For example, if the SC3400 core needs to activate receive channel 2 and the number of
receive buffers is 4 (RNB[3–0] = 0011), it should write the initialization value to the
following addresses (which are offsets from the TDMx receive local memory, see
Chapter 9, Memory Map):
— 0x0010–0x0017 (the channel location in buffer 0).
— 0x0210–0x0217 (the channel location in buffer 1).
— 0x0410–0x0417 (the channel location in buffer 2).
— 0x0610–0x0617 (the channel location in buffer 3).
19.5 Loopback Support
In Loopback Test mode, the receiver receives the same data that is transmitted. The frame clock
should supply to the TDM, and the frame sync can be generated internally or supplied externally.
The receiver and transmitter share the frame sync, frame clock, and data links (RTSAL[3–2] =
0b11). The number of data links can be 1, 2, or 4 and is determined by the RTSAL[1–0] bits. All
the receive and transmit frame channels are active. The procedure for loopback is as follows:
1.
Configure the RTSAL field in the GIR register (see page 19-36) to shared data links
mode- RTSAL[3–2] = 0b11. The number of data links can be 1, 2, or 4.
2.
Configure the receive and transmit frame parameters to be the same. The configuration
of the RFP register should be identical to that of the TFP register (see page 19-48 and
page 19-51).
3.
Configure the TDMx Transmit Interface Register (TDMxTIR) and the TDMx Receive
Interface Register (TDMxRIR) according to the following instructions:
— Set the Transmit Sync Out (TSO) bit to 1. The transmit sync is generated by the TDM.
— Set the Receive Frame Sync Delay field to 0x00 and the Transmit Frame Sync Delay
field to 0x01.
— Set both the Receive Frame Sync Edge (RFSE) bit and the Transmit Frame Sync Edge
(TFSE) bits to 1. The sync samples at the negative edge.
— The value of the Receive Sync level bit should be identical to that of the Transmit Sync
Level field (RSL = TSL).
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...