Jameco Electronics 3000 Manual De Usuario

Figure 12-8 shows the timing relationship among 

, the external serial clock, and 

data receive. Note that RxA is sampled by the rising edge of 

.

When clocking the Rabbit externally, the maximum serial clock frequency is limited by 
the amount of time required to synchronize the external clock with the Rabbit 

.  If 

we sum the maximum number of 

 cycles required to perform clock synchroniza-

tion for each of the receive and transmit cases, then the fastest external serial clock fre-
quency would be limited to 

/6.

Valid

perclk

CLKA 

RxA

(Ext.)