DS90UR907Q_10 Datasheet, PDF (19/26 Pages) National Semiconductor (TI) – 5 - 65 MHz 24-bit Color FPD-Link to FPD-Link II Converter

The third pin is the ID[X] pin. This pin sets one of four possible
device addresses. Two different connections are possible.
The pin may be pulled to V_DD (1.8V, NOT V_DDIO)) with a 10
kΩ resistor. Or a 10 kΩ pull up resistor (to V_DD 1.8V, NOT
V_DDIO)) and a pull down resistor of the recommended value
to set other three possible addresses may be used. See Table
4.
The Serial Bus protocol is controlled by START, START-Re-
peated, and STOP phases. A START occurs when SCL
transitions Low while SDA is High. A STOP occurs when SDA
transition High while SCL is also HIGH. See Figure 22
FIGURE 22. START and STOP Conditions
30105051
To communicate with a remote device, the host controller
(master) sends the slave address and listens for a response
from the slave. This response is referred to as an acknowl-
edge bit (ACK). If a slave on the bus is addressed correctly,
it Acknowledges (ACKs) the master by driving the SDA bus
low. If the address doesn't match a device's slave address, it
Not-acknowledges (NACKs) the master by letting SDA be
pulled High. ACKs also occur on the bus when data is being
transmitted. When the master is writing data, the slave ACKs
after every data byte is successfully received. When the mas-
ter is reading data, the master ACKs after every data byte is
received to let the slave know it wants to receive another data
byte. When the master wants to stop reading, it NACKs after
the last data byte and creates a stop condition on the bus. All
communication on the bus begins with either a Start condition
or a Repeated Start condition. All communication on the bus
ends with a Stop condition. A READ is shown in Figure 23
and a WRITE is shown in Figure 24.
If the Serial Bus is not required, the three pins may be left
open (NC).
TABLE 4. ID[x] Resistor Value – DS90UR907Q
Resistor
RID kΩ
Address
7'b
Address
8'b
0 appended
(WRITE)
0.47
7b' 110 1001 (h'69) 8b' 1101 0010 (h'D2)
2.7
7b' 110 1010 (h'6A) 8b' 1101 0100 (h'D4)
8.2
7b' 110 1011 (h'6B) 8b' 1101 0110 (h'D6)
Open 7b' 110 1110 (h'6E) 8b' 1101 1100 (h'DC)
FIGURE 23. Serial Control Bus — READ
30105038
FIGURE 24. Serial Control Bus — WRITE
30105039
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