FTDI Vinculum-II VNC2-32L1B, Manual

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Copyright © Future Technology Devices International Limited
Datasheet
Vinculum-II Embedded Dual USB Host Controller IC
Version 1.6
Document No.: FT_000138 Clearance No.: FTDI# 143
The command and status formats for this mode can be seen in
Figure
6.7 below with a description of
each field in Table 6.6 :
Command:
Status:
Figure 6.7 SPI Command and Status Structure
Field Description
A2:A0
Address of slave being used in a multi-slave environment. This would typically be used in the
scenario where a shared data bus is used.
R/W# Set to ‘1’ for a read and ‘0’ for a write.
Z Tri-stated.
TXE
Transmit Empty.
When ‘1’ the Slave transmit buffer has no new data to transmit.
When ‘0’ the Slave transmit buffer does have new data.
RXF
Receive Full.
When ‘1’ the Slave receive buffer has new data which has not been read yet.
When ‘0’ the Slave receive buffer is empty and can be safely written to.
ACK Set to ‘1’ when a Slave has correctly decoded its address.
Table 6.6 SPI Command and Status Fields
A2 A1 A0 R/W# Z Z Z Z
Z Z Z Z TXE RXF ACK Z