The TL16C552 is an enhanced dual channel version of the popular TL16C550 asynchronous communications element (ACE). The device serves two serial input/output interfaces simultaneously in microcomputer or microprocessor-based systems. Each channel performs serial-to-parallel conversion on data characters received from peripheral devices or modems and parallel-to-serial conversion on data characters transmitted by the CPU. The complete status of each channel of the dual ACE can be read at any time during functional operation by the CPU. The information obtained includes the type and condition of the transfer operations being performed and the error conditions.

In addition to its dual communications interface capabilities, the TL16C552 provides the user with a fully bidirectional parallel data port that fully supports the parallel Centronics-type printer. The parallel port and the two serial ports provide IBM PC/AT-compatible computers with a single device to serve the three system ports.

A programmable baud rate generator is included that can divide the timing reference clock input by a divisor between 1 and (216 - 1).

The TL16C552 is housed in a 68-pin plastic leaded chip carrier.

• IBM PC/ATTM Compatible
• Two TL16C550 ACEs
• Enhanced Bidirectional Printer Port
• 16-Byte FIFOs Reduce CPU Interrupts
• Independent Control of Transmit, Receive, Line Status, and Data Set Interrupts on Each Channel
• Individual Modem Control Signals for Each Channel
• Programmable Serial Interface Characteristics for Each Channel:
  • 5-, 6-, 7-, or 8-bit Characters
  • Even-, Odd-, or No-Parity Bit Generation and Detection
  • 1-, 1 1/2-, or 2-Stop Bit Generation
• 3-State TTL Drive for the Data and Control Bus on Each Channel
• Hardware and Software Compatible With TL16C452

  IBM PC/AT is a trademark of International Business Machines Corporation.