The ST16C654 *1 is a universal asynchronous receiver and transmitter (UART) with a dual foot print interface compatible with the ST16C554 and ST68C554. The 654 is an enhanced UART with 64 byte FIFOs, automatic hardware/software flow control, and data rates up to 1.5Mbps. Onboard status registers provide the user with error indications and operational status, modem interface control. System interrupts may be tailored to meet user requirements. An internal loopback capability allows onboard diagnostics. The 654 is available in 64 pin TQFP, 68 pin PLCC, and 100 pin QFP packages. The 64 pin package offers the 16 interface mode which is compatible with the industry standard ST16C554. The 68 and 100 pin packages offer an additional 68 mode which allows easy integration with Motorola, and other popular microprocessors. The ST16C654CQ64 (64 pin) offers three state interrupt control while the ST16C654DCQ64 provides constant active interrupt outputs. The 64 pin devices do not offer TXRDY/RXRDY outputs or the default clock select option (CLKSEL). The 100 pin packages offer faster channel status access by providing separate outputs for TXRDY and RXRDY, offer separate Infrared TX outputs and a musical instrument clock input (MIDICLK). The 654 combines the package interface modes of the 16C454/ 554 and 68/C454/554 series on a single integrated chip.