Datasheet

36
MSL2021 [DATASHEET]
42062A–LED–02/2013
Figure 14-11. I
2
C Broadcast Writing a Data Byte
There is no broadcast read. However, a broadcast write may be used to set up the internal register pointers of all the
MSL2021s in a system to speed up the subsequent individual reading of, for example, all the status registers. Figure 14-
12 illustrates a broadcast write that sets all the register pointers, and issues a STOP.
Figure 14-12. I
2
C Broadcast Writing a Register Pointer
SDA
00000000 A 00A D0 A
ACKNOWLEDGE
FROM MSL202x
START STOP
BROADCAST WRITE
SLAVE ADDRESS
MSL202x BROADCAST ID
SETS ALL REGISTER
POINTERS TO X
DATA WRITES TO ALL
REGISTER Xs
D7100001
ALL REGISTER POINTERS NOW POINT TO X + 1; THE FIRST SUBSEQUENT READ
ACCESS OF EACH MSL202x READS FROM REGISTER ADDRESS X + 1
ACKNOWLEDGE
FROM MSL202x
......
D0 AD7
......
ACKNOWLEDGE
FROM MSL202x
ACKNOWLEDGE
FROM MSL202x
SDA
00000000 A 00A D0 A
ACKNOWLEDGE
FROM MSL202x
START STOP
BROADCAST WRITE
SLAVE ADDRESS
MSL202x BROADCAST ID
SETS ALL REGISTER
POINTERS TO X
D7100001
ALL REGISTER POINTERS NOW POINT TO X; THE FIRST SUBSEQUENT READ ACCESS
OF EACH MSL202x BEGINS READING FROM REGISTER ADDRESS X
......
ACKNOWLEDGE
FROM MSL202x
ACKNOWLEDGE
FROM MSL202x