VNC1L-1A-REEL Datasheet, PDF (13/32 Pages) Future Technology Devices International Ltd. – Future Technology Devices International Ltd.

Document Reference No.: FT_000030
Vinculum VNC1L Embedded USB Host Controller IC Datasheet Version 2.02
Clearance No.: FTDI# 50
which allows VNC1L to be programmed using this method. The TEST pin is used in manufacturing to
enhance the testability of the various internal blocks and should be tied to GND.
DMA Controller 1 and 2 - The twin DMA controllers in VNC1L greatly enhance performance by allowing
data from the two USB SIE controllers, UART, FIFO and SPI interfaces to be transferred between each
other via the data SRAM with minimal MCU intervention.
Data SRAM - This 4k x 8bit block acts as the data (variable) memory for the Vinculum MCU, though it
can also be accessed transparently to the MCU by the twin DMA controllers.
NPU (Numeric Co-processor) – Operations which extensively utilise 32-bit arithmetic, such as
calculations relating to the FAT file system, are enhanced by the 32-bit co-processor block.
UART Prescaler - This block provides the master transmit/receive clock for the UART block. By varying
the prescaler value, the baud rate of the UART can be adjusted over a range of 300baud to 1Mbaud.
System Timer - The system timer provides a regular interrupt to VNC1L firmware.
Vinculum MCU Core – Processor core based on FTDI‟s proprietary 8-bit embedded MCU architecture.
VMCU has a Harvard architecture i.e. separate code and data space. It supports 64k bytes of program
code, 64k bytes of (paged) data space and 256 bytes of I/O space and uses “enhanced CISC” technology.
Typically VMCU instructions replace several lines of code in conventional CISC or RISC processors giving
RISC like performance in CISC architecture with the advantage over both of excellent code compression
in the program ROM space.
E-FLASH Program ROM - The VNCL1L has 64k bytes of embedded Flash (E-FLASH) memory. No special
programming voltages are necessary for programming the onboard E-FLASH as these are provided
internally on-chip. VNC1L devices are supplied blank and require to be initially programmed using the
Bootstrap Loader.
Bootstrap Loader ROM - This is a small block of hard-coded ROM (512 x 8 bits) which bypasses the
main E-FLASH memory when PROG# is pulled low. This provides a means of programming the entire E-
FLASH memory via the UART interface. A blank device must be programmed with the Bootstrap Loader
via the UART interface. A device already programmed may be upgraded via either the UART interface or
the USB interface.
UART and FIFO Logic - Optional serial and parallel interfaces to VNC1L that are equivalent to the
interfaces on FTDI‟s FT232 and FT245 ICs.
GPIO Blocks - General purpose I/O pins. Not all I/O pins are available to the user for a particular
configuration. Restrictions on use are shown in Table 3.4.
4.3 Programming VNC1L
The VNC1L is shipped as a blank device. It must be programmed (when in bootloader mode) with
firmware before use. It can be programmed either pre-assembly, using the VPROG-1 stand alone
programmer or programmed in-circuit via the UART interface.
The VNC1L bootloader uses the UART interface to load new firmware into the Vinculum Flash memory. To
enable the bootloader, the PROG# pin must be driven low and VNC1L must then be reset by driving the
RESET# pin low then high. Run mode can be enabled by driving the PROG# pin high and then resetting
VNC1L by driving the RESET# pin low then high.
When VNC1L firmware is updated via a microcontroller with a UART, the microcontroller must be capable
of at least 115200 baud.
The firmware can be upgraded in to the Flash memory via the UART interface or via a USB interface.
Examples of how to connect VNC1L in each of these modes is given in http://www.ftdichip.com
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