Filter
Top Products
75 www.national.com
CP3BT26
Figure 18. 32-Bit Write Timing
Figure 19. 32-Bit Read Timing
An example of a 32-bit write is shown in Table 31. In this ex-
ample, the 32-bit value FFFF DC04h is written to register
address 0Ah. In cycle 1, the high word (FFFFh) is written. In
the first part of cycle 2, the CP3BT26 drives the header, R/
W bit, and register address for a read cycle. In the second
part of cycle 2, the LMX5252 drives the counter value. The
counter value is 0, which indicates one word has been writ-
ten. In cycle 3, the low word (DC04h) is written. In the first
part of cycle 4, the CP3BT26 drives the header, R/W bit,
and register address for a read cycle. In the second part of
cycle 4, the LMX5252 drives the counter value. The counter
value is 1, which indicates two words have been written.
SLE
SCLK
SDAT
DS322
D16D30A0A1A2A3A4WH0H1H2 D31 D0D14A0A1A2A3A4WH0H1H2 D15
>500 ns
SLE
SCLK
SDAT
DS323
D16D31A0A1A2A3A4RH0H1H2 D0D15A0A1A2A3A4RH0H1H2
>500 ns
Table 31 Example of 32-Bit Write with Interleaved Reads
Cycle Serial Data on SDAT Description
1
101 0 01010 1111111111111111
Write cycle driven by CP3BT26. Data is FFFFh. Address is 0Ah.
2
101 1 01010
First part of read cycle driven by CP3BT26. Address is 0Ah.
0000000000000000
Second part of read cycle driven by LMX5252. Counter value is 0.
3
101 0 01010 1101110000000100
Write cycle driven by CP3BT26. Data is DC04h. Address is 0Ah.
4
101 1 01010
First part of read cycle driven by CP3BT26. Address is 0Ah.
0000000000000001
Second part of read cycle driven by LMX5252. Counter value is 1.