VNC2-48Q1B-REEL FTDI, VNC2-48Q1B-REEL Datasheet - Page 46

• Manufacturer Part Number: VNC2-48Q1B-REEL
• Description: USB Interface IC Vinculum-II Dual USB Host/Dev IC QFN-48
• Manufacturer: FTDI
• Type: USB Host/Device Controllerr

Specifications of VNC2-48Q1B-REEL

• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Operating Temperature Range: - 40 C to + 85 C
• Supply Current: 25 mA
• Operating Supply Voltage: 1.8 V, 3.3V
• Package / Case: QFN-48
• Description/function: USB Vinculum-II Dual Host/Dev IC QFN-48
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: VINCULUM2

6.3.3 Half Duplex, 4 pin
In half duplex mode, the MOSI signal is shared for both Master to Slave and Slave to Master
communications. When using 4 pins, the MISO signal carries the status bits. The Master initiates data
write transfer, this by asserting SS# and then sending out a command byte. This has the same format as
that shown in Figure 6-7. The Slave sends status during this command phase and if this indicates that
the Slave can accept data the Master will follow this up with a byte of write data. If the status continues
to indicate that more data can be written, a whole stream of data can be written following one single
command. The operation completes when the Master raises SS# again. Figure 6-8 is an example of this.
Figure 6-8 Half Duplex Data Master Write
Data reads are similar, apart from the MOSI pin changing from Slave input to Slave output after the
command phase. Figure 6-9 is an example. In this diagram, the Master drives the command while the
Slave returns with status. Then the MOSI buffers are turned round and a stream of read data is sent from
the Slave to the Master on the MOSI signal.
Figure 6-9 Half Duplex Data Master Read
MOSI
MOSI
MISO
MISO
SS#
SS#
Master to Slave
Copyright © 2010 Future Technology Devices International Limited
8 bit CMD
8 bit CMD
STATUS
STATUS
VINCULUM-II EMBEDDED DUAL USB HOST CONTROLLER IC Datasheet
STATUS
STATUS
W0
R0
Slave to Master
STATUS
STATUS
W1
R1
Document No.: FT_000138
Clearance No.: FTDI#
STATUS
STATUS
W2
R2
Version -
143
1.2
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