TDM Basics
MSC8113 Reference Manual, Rev. 0
Freescale Semiconductor
20-13
Table 20-3 describes the maximum TDM bit rate when the system bus clock works at its typical
value of 133 MHz.
20.2.3 TDM Data Structures
TDM data structures are stored in transmit and receive local memory, as follows:
TDM receive local memory. Received data is stored in 256 8-byte entries located in
addresses between 0x0000–0x07FF, which is offset from the TDMx receive local memory
(see Chapter 8, Memory Map). This memory contains 1, 2, 4, 8, 16, or 32 indexed buffers
starting at 0. Each buffer contains multiple frames. The number of buffers used to store the
received data is indicated in the RNB field of the TDMx Receive Number of Buffers
Register (TDMxRNB) (discussed on page 20-64). Channel C in buffer B is the 8 bytes
starting at (256/(RNB + 1)
×
B + C)
×
8.
TDM transmit local memory. Transmit data is located in the TDM local memory before it
is transmitted externally. The data is stored in 256 8-byte entries in addresses between
0x1800– 0x1FFF, which is offset from the TDMx receive local memory (see Chapter 8,
Memory Map). This memory can contain 1, 2, 4, 8, 16, or 32 indexed buffers starting at 0.
Each buffer contains multiple frames. The number of buffers used to store the transmitted
data is indicated in the TNB field of the TDMx Transmitter Number of Buffers Register
(TDMxTNB). Channel C in buffer B is the 8 bytes starting at (256/(TNB + 1)
×
B + C)
×
8.
Figure 20-15 shows an example of TDM local memory that contains four transmit buffers and
one receive buffer. Up to 32 transmit bytes of channel 2 are located in four buffers (TNB = 3).
Only 8 receive bytes of channel 2 are located in one buffer (RNB = 0). Each buffer contains 8
bytes per channel.
Table 20-2. Factors Affecting Maximum Bit Rate
Channel Width (Bits)
1 Active Link
2 Active Links
4 Active Links
2
BUSES_CLOCK/8
BUSES_CLOCK/12 BUSES_CLOCK/20
4
BUSES_CLOCK/4
BUSES_CLOCK/6 BUSES_CLOCK/10
8
BUSES_CLOCK/2 BUSES_CLOCK/3 BUSES_CLOCK/5
16
BUSES_CLOCK/2 BUSES_CLOCK/2 BUSES_CLOCK/2.5
Table 20-3. Maximum Bit Rate When the System Bus Clock Runs at 133 MHz
Channel Width (Bits)
1 Active Link
2 Active Links
4 Active Links
2
16.63 Mbps
11.08 Mbps
6.65 Mbps
4
33.25 Mbps
22.17 Mbps
13.3 Mbps
8
66.5 Mbps
44.3 Mbps
26.6 Mbps
16
66.5 Mbps
66.5 Mbps
53.2 Mbps
Summary of Contents for MSC8113
Page 1: ...MSC8113 Reference Manual Tri Core 16 Bit Digital Signal Processor MSC8113RM Rev 0 May 2008 ...
Page 20: ...MSC8113 Reference Manual Rev 0 xx Freescale Semiconductor Contents ...
Page 28: ...MSC8113 Reference Manual Rev 0 xxviii Freescale Semiconductor ...
Page 56: ...MSC8113 Reference Manual Rev 0 1 28 Freescale Semiconductor MSC8113 Overview ...
Page 76: ...MSC8113 Reference Manual Rev 0 2 20 Freescale Semiconductor SC140 Core Overview ...
Page 134: ...MSC8113 Reference Manual Rev 0 4 30 Freescale Semiconductor System Interface Unit SIU ...
Page 168: ...MSC8113 Reference Manual Rev 0 6 18 Freescale Semiconductor Boot Program ...
Page 180: ...MSC8113 Reference Manual Rev 0 7 12 Freescale Semiconductor Clocks ...
Page 260: ...MSC8113 Reference Manual Rev 0 8 80 Freescale Semiconductor Memory Map ...
Page 300: ...MSC8113 Reference Manual Rev 0 9 40 Freescale Semiconductor Extended Core ...
Page 304: ...MSC8113 Reference Manual Rev 0 10 4 Freescale Semiconductor MQBus and M2 Memory ...
Page 308: ...MSC8113 Reference Manual Rev 0 11 4 Freescale Semiconductor SQBus ...
Page 590: ...MSC8113 Reference Manual Rev 0 17 46 Freescale Semiconductor Interrupt Processing ...
Page 614: ...MSC8113 Reference Manual Rev 0 18 24 Freescale Semiconductor Debugging ...
Page 622: ...MSC8113 Reference Manual Rev 0 19 8 Freescale Semiconductor Internal Peripheral Bus IPBus ...
Page 724: ...MSC8113 Reference Manual Rev 0 21 32 Freescale Semiconductor UART ...
Page 920: ...MSC8113 Reference Manual Rev 0 25 150 Freescale Semiconductor Ethernet Controller ...
Page 1171: ...MSC8113 Reference Manual Rev 0 Freescale Semiconductor C 61 EF wait_rts P 01077FFC 9F rts 71 ...
Page 1172: ...MSC8113 Reference Manual Rev 0 C 62 Freescale Semiconductor MSC8113 Boot Code ...
Page 1202: ...MSC8113 Reference Manual Rev 0 Index 30 Freescale Semiconductor Index ...