Datasheet

SPI
Intel
®
Quark™ microcontroller D2000
January 2016 Datasheet
Document Number: 333577-002EN 233
Bits Access
Type
Default Description PowerWell ResetSignal
9:8 RW/L 2'h0 Transfer Mode (TMOD)
Transfer Mode. Selects the
mode of transfer for serial
communication. This field
does not affect the transfer
duplicity. Only indicates
whether the receive or
transmit data are valid. In
transmit-only mode, data
received from the external
device is not valid and is not
stored in the receive FIFO
memory; it is overwritten on
the next transfer. In receive-
only mode, transmitted data
are not valid. After the first
write to the transmit FIFO,
the same word is
retransmitted for the
duration of the transfer. In
transmit-and-receive mode,
both transmit and receive
data are valid. The transfer
continues until the transmit
FIFO is empty. Data received
from the external device are
stored into the receive FIFO
memory, where it can be
accessed by the host
processor. In eeprom-read
mode, receive data is not
valid while control data is
being transmitted. When all
control data is sent to the
EEPROM, receive data
becomes valid and transmit
data becomes invalid. All
data in the transmit FIFO is
considered control data in
this mode. This transfer
mode is only valid when the
SPI Controller is configured
as a master device.
00 - Transmit & Receive
01 - Transmit Only
10 - Receive Only
11 - EEPROM Read