Figure 3.2.1
The DNT90M SPI port can run at three clock rates in master mode - 125, 250 or 500 kbps. There are two message
sources available to a DNT90M SPI master, a protocol-formatted
RxData
message or a stored command. The DNT90M
master will clock a message from either source into its slave and return the bytes clocked out as a protocol-formatted
TxData
message. The DNT90M event timer triggers sending the stored command to the DNT90M’s slave. The stored
command can be up to 16 bytes in length. Figure 3.2.1 shows the required SPI master mode-signal connections, and Fig-
ure 3.2.2 shows the SPI master-mode timing.
Figure 3.2.2
In SPI slave mode, the host can stream data into DNT90M at up to 250 kbps, provided the host suspends clocking within
10 bytes following a low-to-high transition on /HOST_CTS. The host can clock data into the DNT90M at up to 4 Mbps for
data bursts of up to 50 bytes, provided the interval from the end of one burst to the start of the next burst is at least 2 ms,
and the host suspends clocking on a low-to-high transition on /HOST_CTS. See Figure 3.2.4.
©2012 by Murata Electronics N.A., Inc.
DNT90M Integration Guide (2012/09/17)
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