Datasheet

Send Byte
The send byte protocol allows the master device to send
one byte of data to the slave device (see Figure 12). The
send byte presets a register pointer address for a subse-
quent read or write. The slave sends a NACK instead of
an ACK if the master tries to send a memory address or
command code that is not allowed. If the master sends
94h or 95h, the data is ACK, because this could be the
start of the write block or read block. If the master sends
a STOP condition before the slave asserts an ACK, the
internal address pointer does not change. If the master
sends 96h, this signifies a software reboot. The send byte
procedure is the following:
1) The master sends a START condition.
2) The master sends the 7-bit slave address and a write
bit (low).
3) The addressed slave asserts an ACK on SDA.
4) The master sends an 8-bit memory address or com-
mand code.
5) The addressed slave asserts an ACK (or NACK) on
SDA.
6) The master sends a STOP condition.
Receive Byte
The receive byte protocol allows the master device to
read the register content of the MAX16046/MAX16048
(see Figure 12). The EEPROM or register address must
be preset with a send byte or write word protocol first.
Once the read is complete, the internal pointer increases
by one. Repeating the receive byte protocol reads the
contents of the next address. The receive byte procedure
follows:
1) The master sends a START condition.
2) The master sends the 7-bit slave address and a read
bit (high).
3) The addressed slave asserts an ACK on SDA.
4) The slave sends 8 data bits.
5) The master asserts a NACK on SDA.
6) The master generates a STOP condition.
Write Byte
The write byte protocol (see Figure 12) allows the master
device to write a single byte in the default page, extended
page, or EEPROM page, depending on which page is cur-
rently selected. The write byte procedure is the following:
1) The master sends a START condition.
2) The master sends the 7-bit slave address and a write
bit (low).
3) The addressed slave asserts an ACK on SDA.
4) The master sends an 8-bit memory address.
5) The addressed slave asserts an ACK on SDA.
6) The master sends an 8-bit data byte.
7) The addressed slave asserts an ACK on SDA.
8) The master sends a STOP condition.
To write a single byte, only the 8-bit memory address and
a single 8-bit data byte are sent. The data byte is written
to the addressed location if the memory address is valid.
The slave will assert a NACK at step 5 if the memory
address is not valid.
Read Byte
The read byte protocol (see Figure 12) allows the master
device to read a single byte located in the default page,
extended page, or EEPROM page depending on which
page is currently selected. The read byte procedure is
the following:
1) The master sends a START condition.
2) The master sends the 7-bit slave address and a write
bit (low).
3) The addressed slave asserts an ACK on SDA.
4) The master sends an 8-bit memory address.
5) The addressed slave asserts an ACK on SDA.
6) The master sends a REPEATED START condition.
7) The master sends the 7-bit slave address and a read
bit (high).
8) The addressed slave asserts an ACK on SDA.
9) The slave sends an 8-bit data byte.
10) The master asserts a NACK on SDA.
11) The master sends a STOP condition.
If the memory address is not valid, it is NACKed by the
slave at step 5 and the address pointer is not modified.
MAX16046/MAX16048 12-Channel/8-Channel EEPROM-Programmable
System Managers with Nonvolatile Fault Registers
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