TL16C550CFNG4

TL16C550CFNG4 1 Features

TL16C550CFNG4 2 Description

the TL16C550C andthe TL16C550CI areThe TL16C550C andfunctional upgrades of the TL16C550B asynchronouscommunications element (ACE), which in turn is afunctional upgrade of the TL16C450. Functionallyequivalent to the TL16C450 on power up (characteror TL16C450 mode),theTL16C550CI, like the TL16C550B, can be placedin an alternate FIFO mode. This relievestheCPU of excessive software overhead by bufferingreceived and transmitted characters. The receiverand transmitter FIFOs store up to 16 bytes includingthree additional bits of error status per byte for thereceiver FIFO. In the FIFO mode, there is a selectableautoflow control feature that can significantly reducesoftware overload and increase system efficiency byautomatically controlling serial data flow using RTSoutput and CTS input signals.The TL16C550C and TL16C550CI perform serial-to-parallel conversions on data received from aperipheral device or modem and parallel-to-serialconversion on data received from its CPU. TheCPU can read the ACE status at any time. TheACE includes complete modem control capabilityand a processorthat can betailored to minimize software management of thecommunications link.interrupt systemBoth the TL16C550C and the TL16C550CI ACEinclude a programmable baud rate generator capableof dividing a reference clock by divisors from 1 to65535 and producing a 16× reference clock for theinternal transmitter logic. Provisions are included touse this 16× clock for the receiver logic. The ACEaccommodates a 1-Mbaud serial rate (16-MHz inputclock) so that a bit time is 1 μs and a typical charactertime is 10 μs (start bit, 8 data bits, stop bit).Two of the TL16C450 terminal functions on theTL16C550C and the TL16C550CI have been changedto TXRDY and RXRDY, which provide signaling to aDMA controller.
• Programmable Auto-RTS and Auto-CTS
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•In Auto-CTSMode, CTS Controls TransmitterIn Auto-RTS Mode, RCV FIFO Contents andThreshold Control RTS
• Serial and Modem Control Outputs Drive a RJ11Cable Directly When Equipment Is on the SamePower Drop
• Capable of Running With All Existing TL16C450Software
• After Reset, All Registers Are Identical to theTL16C450 Register Set
• Up to 16-MHz Clock Rate for up to 1-Mbaud
•OperationIn the TL16C450 Mode, Hold and Shift RegistersEliminate the Need for Precise SynchronizationBetween the CPU and Serial Data
• Programmable Baud Rate Generator AllowsDivision of Any Input Reference Clock by 1 to (216−1) and Generates an Internal 16×Clock
• Standard Asynchronous Communication Bits(Start, Stop, and Parity) Added to or Deleted Fromthe Serial Data Stream
• 5-V and 3.3-V Operation
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• Transmit, Receive, Line Status, and Data SetIndependent Receiver Clock InputInterrupts Independently Controlled
• Fully Programmable Serial InterfaceCharacteristics:– 5-, 6-, 7-, or 8-Bit Characters– Even-, Odd-, or No-Parity Bit Generation andDetection– 1-, 1 1/2-, or 2-Stop Bit Generation– Baud Generation (dc to 1 Mbit/s)
• False-Start Bit Detection
• Complete Status Reporting Capabilities
• 3-State Output TTL Drive Capabilities forBidirectional Data Bus and Control Bus
• Line Break Generation and Detection
•Internal Diagnostic Capabilities:– Loopback Controls for Communications LinkFault Isolation– Break, Parity, Overrun, and Framing ErrorSimulation
• Fully Prioritized Interrupt System Controls
• Modem Control Functions (CTS, RTS, DSR, DTR,RI, and DCD)