M4T28-BR12SH ST Microelectronics, M4T28-BR12SH Datasheet - Page 14

• Manufacturer Part Number: M4T28-BR12SH
• Description: TIMEKEEPER SNAPHAT Battery & Crystal
• Manufacturer: ST Microelectronics

M41ST85Y, M41ST85W
Figure 15. Alternate READ Mode Sequence
WRITE Mode
In this mode the master transmitter transmits to
the M41ST85Y/W slave receiver. Bus protocol is
shown in Figure 16, page 14. Following the
START condition and slave address, a logic '0' (R/
W=0) is placed on the bus and indicates to the ad-
dressed device that word address An will follow
and is to be written to the on-chip address pointer.
The data word to be written to the memory is
Figure 16. WRITE Mode Sequence
14/33
BUS ACTIVITY:
MASTER
SDA LINE
BUS ACTIVITY:
BUS ACTIVITY:
MASTER
SDA LINE
BUS ACTIVITY:
S
ADDRESS
SLAVE
S
ADDRESS
SLAVE
ADDRESS (An)
WORD
DATA n
strobed in next and the internal address pointer is
incremented to the next memory location within
the RAM on the reception of an acknowledge
clock. The M41ST85Y/W slave receiver will send
an acknowledge clock to the master transmitter af-
ter it has received the slave address (see Figure
13, page 13) and again after it has received the
word address and each data byte.
DATA n
DATA n+1
DATA n+1
DATA n+X
DATA n+X
AI00895
AI00591
P
P