VNC2-48Q1B-REEL FTDI, VNC2-48Q1B-REEL Datasheet - Page 47

• 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

6.3.4 Half Duplex, 3 pin
The 3 pin half duplex mode eliminates the MISO pin from the protocol. This means that status bytes need
to be sent on the MOSI pin. Again the Master initiates a transfer by asserting SS# and sending out a
command byte. The Slave sends status back to the Master. If a write has been requested and the status
indicates that the Slave can accept data, MOSI should be changed to an output again and data will be
sent from Master to Slave.
Following this data, the Slave will send a further status byte if SS# remains active. If the status indicates
that more data can be written, the next data byte can be sent to the Slave and this process continues
until SS# is de-asserted. Figure 6-10 is an example of this:
Figure 6-10 Half Duplex 3-pin Data Master Write
Data reads are similar expect that after the command byte all data transfer is from Slave to Master.
Figure 6-11 is an example of this:
Figure 6-11 Half Duplex 3-pin Data Master Read
MOSI
MOSI
SS#
SS#
Master to Slave
Master to Slave
Copyright © 2010 Future Technology Devices International Limited
8 bit CMD
8 bit CMD
VINCULUM-II EMBEDDED DUAL USB HOST CONTROLLER IC Datasheet
Slave to Master
STATUS
STATUS
Master to Slave
W0
R0
Slave to Master
Slave to Master
STATUS
STATUS
Document No.: FT_000138
Clearance No.: FTDI#
Master to Slave
Version -
W1
R1
143
1.2
47