VNC2-48L1B FTDI, VNC2-48L1B Datasheet - Page 62

• Manufacturer Part Number: VNC2-48L1B
• Description: CONTROLLER, USB, VINCULUM II, 48LQFP
• Manufacturer: FTDI

Specifications of VNC2-48L1B

• Usb Type: Host Controller
• Usb Version: 2.0
• Data Rate: 12Mbps
• No. Of Ports: 2
• Supply Voltage Range: 1.62V To 1.98V, 2.97V To 3.63V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case: RoHS Compliant

Document No.: FT_000138
VINCULUM-II EMBEDDED DUAL USB HOST CONTROLLER IC Datasheet
1.2
Version -
143
Clearance No.: FTDI#
6.6.2 Read / Write Transaction Asynchronous FIFO Mode
When in Asynchronous FIFO interface mode, the timing of read and write operations on the FIFO
interface are shown in Figure 6-22 and Table 29.
In asynchronous mode an external device can control data transfer driving FIFO_WR# and FIFO_RD#
inputs. In contrast to synchronous mode, in asynchronous mode the 245 FIFO module generates the
output enable EN# signal. EN# signal is effectively the read signal RD#.
Current byte is available to be read when FIFO_RD# goes low. When FIFO_RD# goes high, FIFO_RXF#
output will also go high. It will only become low again when there is another byte to read.
When FIFO_WR# goes low FIFO_TXE# flag will always go high. FIFO_TXE# goes low again only when
there is still space for data to be written in to the module.
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