VPU 16551 UART

If you are looking for a Compact Flash UART bridge solution then the VPU16551 is the perfect choice. Compact Flash designs pose some serious challenges for the card designer, especially when you need to integrate numerous other devices into your solution. To address this the VPU16551 uses a tiny 8x8mm BGA package standing just 1.1mm (typ.) off the PCB (allowing reverse side or top side PCB mounting).

That's not the only advantage with the VPU16551...it also integrates the parallel EEPROM used for the Card Information Structure, meaning that this is truly a single chip solution. You get all the flexibility to reprogram the CIS as many times as you like, plus store any serial number or production lot data into the card while the VPU is in-circuit.

The VPU, standing for Versatile PC Card UART, implements all the required decoding and protocol logic for the host interface, integrated with an industry standard 16550 UART (Universal Asynchronous Receiver Transmitter). This allows direct connection to any asynchronous device at up to 2.5MBaud.

The VPU chip, programmed with a suitable Card Information Structure will use the default drivers from all Windows Operating Systems; that's Windows95, 98, 98SE, ME, 2000, XP, CE, PocketPC, MacOS. The VPU will also work with DOS drivers from companies like SystemSoft and Award.

The VPU also implements some novel features beyond the normal operation of the UART, to allow proprietary capabilities to be added to the card design, but without needing to write kernel device drivers.

To aid developers with the use and productionisation of their card, there is a VPU reference kit that includes chips, software tools, schematics and sample CIS data.

The VPU16551 is ideally suited to the creation of Compact Flash Cards that require a standard "COM" port type functionality, for example :

• Bluetooth radio RS232, 422, 485 interface cards
• Scanner interface
• Smart transmitters / tags
• RF modules with serial I/O
• GSM, GPRS radio modules
• CDMA radio modules
• GPS modules

 => User Guide !!

Technical Features

• 16C550 compatable UART with 16-byte TX and RX FIFOs
   for high speed and reliable communications

• Integrated parallel EEPROM, re-programmable in-circuit
   (with software un-lock mechanism)

• Ultra-thin 64 ball BGA package, just 8mm x 8mm x 1.1mm typ.

• Supports industry standard baud rates and enhanced x8 mode
   to reach up to 2.5MBaud

• Supports PCMCIA and Compact Flash interfaces

• Very simple to use, no specialized knowledge required

• "Parallel port" access to TX and RX buffers (from card side)
    for design that cannot use serial

• Built-in pull-up and pull-down resistors

• UART register activity LED driver

• Signal for RS485 auto-tristate called "TXRDY" is provided

• Support for crystal oscillator or external TTL clock drive

• Multi-function support...up to 2 VPUs in one card, or share
   with another ogical function

• Supported by standard drivers in DOS, Windows95, 98, 98SE,
   Me, 2000, XP, CE/ Pocket PC, MacOS.

• Enhanced driver for PocketPC also available to support extended
   features of the VPU (other OS support is coming soon)

• Low power consumption: Typical 5mA at 5V or 3.3V.  Support for
   reduced power sleep mode by oscillator stop, current drops to <100uA

• Software controlled power-down signal available at pin for use
   with your circuit.