Motorola MPC8260 User Manual
MOTOROLA
Chapter 28. Fast Communications Controllers (FCCs)
28-1
Chapter 28
Fast Communications Controllers
(FCCs)
Fast Communications Controllers
(FCCs)
280
280
The MPC8260Õs fast communications controllers (FCCs) are serial communications
controllers (SCCs) optimized for synchronous high-rate protocols. FCC key features
include the following:
controllers (SCCs) optimized for synchronous high-rate protocols. FCC key features
include the following:
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Supports HDLC/SDLC and totally transparent protocols
¥
FCC clocks can be derived from a baud-rate generator or an external signal.
¥
Supports RTS, CTS, and CD modem control signals
¥
Use of bursts to improve bus usage
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Multibuffer data structure for receive and transmit, external buffer descriptors (BDs)
anywhere in system memory
anywhere in system memory
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192-byte FIFO buffers
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Full-duplex operation
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Fully transparent option for one half of an FCC (receiver/transmitter) while HDLC/
SDLC protocol executes on the other half (transmitter/receiver)
SDLC protocol executes on the other half (transmitter/receiver)
¥
Echo and local loopback modes for testing
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Assuming a 100-MHz CPM clock, the FCCs support the following:
Ñ Full 10/100-Mbps Ethernet/IEEE 802.3x through an MII
Ñ Full 155-Mbps ATM segmentation and reassembly (SAR) through UTOPIA (on
FCC1 and FCC2 only)
Ñ 45-Mbps (DS-3/E3 rates) HDLC and/or transparent data rates supported on each
FCC
FCCs differ from SCCs as follows:
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No DPLL support.
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No BISYNC, UART, or AppleTalk/LocalTalk support.
¥
No HDLC bus.
¥
Ethernet support only through an MII.