Datasheet

429
SAM3X / SAM3A [DATASHEET]
Atmel-11057C-ATARM-SAM3X-SAM3A-Datasheet_23-Mar-15
25.10.2.1 Read is Controlled by NRD (READ_MODE = 1):
Figure 25-8 shows the waveforms of a read operation of a typical asynchronous RAM. The read data is available
t
PACC
after the falling edge of NRD, and turns to ‘Z’ after the rising edge of NRD. In this case, the READ_MODE
must be set to 1 (read is controlled by NRD), to indicate that data is available with the rising edge of NRD. The
SMC samples the read data internally on the rising edge of Master Clock that generates the rising edge of NRD,
whatever the programmed waveform of NCS may be.
Figure 25-8. READ_MODE = 1: Data is sampled by SMC before the rising edge of NRD
Data Sampling
t
PACC
MCK
A[23:2]
NBS0,NBS1,
A0, A1
NCS
NRD
D[15:0]