Preliminary

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FIGURE 9. Unidirectional Serializer and Deserializer

FIGURE 10. Multiple Units, Unidirectional Signals in Each Direction

Figure 10 shows a half duplex connectivity diagram. This

connectivity allows for two unidirectional data streams to

be sent across a single pair of SerDes devices. Data will be

sent on a frame by frame basis. For this mode of operation

to work there needs to be some synchronization between

when the Camera sends its data frame and when the LCD

sends its data. One option for this is to have the LCD send

data during the camera blanking period. External logic may

need to be provided in order for this mode of operation to

work.

Devices will alternate frames of data controlled by a direc-

tion control and a direction sense. When DIRI, on the right-

hand FIN24A is HIGH, data will be sent from the Camera to

the Camera interface at the base. When DIRI, on the right-

hand FIN24A goes LOW data will be sent from the base-

band process to the LCD. The direction is then changed at

DIRO on the right-hand FIN24A indicating to the left-hand

FIN24A to change direction. Data will be sent from the

Base LCD Unit to the LCD. The DIRO pin on the left-hand

FIN24A is used to indicate to the base control unit that the

signals are changing direction and the LCD is now avail-

able to be sent data. DIRI on the right-hand FIN24A could

typically use a timing reference signal such as VSYNC

from the camera interface to indicate direction change. A

derivative of this signal may be required in order to make

sure that no data is lost on the final data transfer.