atr2434 ATMEL Corporation, atr2434 Datasheet - Page 7

• Manufacturer Part Number: atr2434
• Description: Wirelessusb 2.4-ghz Dsss Radio Soc - Atmel Corporation
• Manufacturer: ATMEL Corporation

Figure 3. SPI Single Read Sequence
Figure 4. SPI Burst Read Sequence
Figure 5. SPI Single Write Sequence
4822C–ISM–09/04
M O S I
M IS O
M O S I
M IS O
M OS I
M ISO
S C K
S C K
SCK
S S
S S
SS
c m d
D IR
D IR
c m d
cm d
DIR
0
0
1
IN C
IN C
INC
0
1
0
A 5
A 5
A5
The SPI communications interface has a burst mechanism, where the command byte
can be followed by as many data bytes as desired. A burst transaction is terminated by
deasserting the slave select (SS = 1).
The SPI communications interface single read and burst read sequences are shown in
Figure 3 and Figure 4, respectively.
The SPI communications interface single write and burst write sequences are shown in
Figure 5 and Figure 6 on page 8, respectively.
Table 1. SPI Transaction Format
A 4
Bit #
Bit Name
A 4
A4
a d d r
a d d r
addr
A 3
A 3
A3
A 2
A 2
A2
A 1
A 1
A1
A 0
A 0
A0
D 7
D 7
D7
D 6
D 6
D6
data from m cu
d a ta to m c u
d a ta to m c u
D 5
D 5
D5
D 4
D 4
D4
DIR
7
D 3
D 3
D3
D 2
D 2
D 2
Byte 1
1
D 1
D 1
D1
D 0
D 0
D 0
INC
D 7
6
ATR2434 [Preliminary]
D 6
d a ta to m c u
D 5
D 4
D 3
D 2
Address
1 + N
[5:0]
D 1
D 0
Byte 1 + N
Data
[7:0]
7