AMI Semiconductor, Inc.
READ Operations
N64S0818HDA/N64S0830HDA
Advance Information
The serial SRAM READ is selected by enabling CS low. First, the 8-bit READ instruction is transmitted to
the device followed by the 16-bit address with the 3 MSBs being don’t care. After the READ instruction
and addresses are sent, the data stored at that address in memory is shifted out on the SO pin after the
output valid time from the clock edge.
If operating in page mode, after the initial word of data is shifted out, the data stored at the next memory
location on the page can be read sequentially by continuing to provide clock pulses. The internal address
pointer is automatically incremented to the next higher address on the page after each word of data is read
out. This can be continued for the entire page length of 32 words long. At the end of the page, the
addresses pointer will be wrapped to the 0 word address within the page and the operation can be
continuously looped over the 32 words of the same page.
If operating in burst mode, after the initial word of data is shifted out, the data stored at the next memory
location can be read sequentially by continuing to provide clock pulses. The internal address pointer is
automatically incremented to the next higher address after each word of data is read out. This can be
continued for the entire array and when the highest address is reached (1FFFh), the address counter
wraps to the address 0000h. This allows the burst read cycle to be continued indefinitely.
All READ operations are terminated by pulling CS high.
Word READ Sequence
CS
SCK
0
1
2
3
4
5
6
7
8
9
10
11
21
22
23
24
25
26
27
28
29
30
31
Instruction
SI
0
0
0
0
0
0
1
1
15
14
16-bit address
13
12
2
1
0
Data Out
SO
High-Z
7
6
5
4
3
2
1
0
7
This is a developmental specification and is subject to change without notice.
AMI [ AMI SEMICONDUCTOR ]
