MCP79401 MICROCHIP [Microchip Technology], MCP79401 Datasheet - Page 9

• Manufacturer Part Number: MCP79401
• Manufacturer: MICROCHIP [Microchip Technology]

3.1.3
Since the device will not acknowledge a Unique ID
command during an ID write cycle, this can be used to
determine when the cycle is complete. This feature can
be used to maximize bus throughput. Once the Stop
condition for a Write command has been issued from
the master, the device initiates the internally timed write
cycle. ACK polling can be initiated immediately. This
involves the master sending a Start condition, followed
by the control byte for a Write command (R/W = 0). If
the device is still busy with the write cycle, then no ACK
will be returned. If no ACK is returned, then the Start bit
and control byte must be resent. If the cycle is
complete, then the device will return the ACK, and the
master can then proceed with the next Read or Write
command. See
FIGURE 3-4:
 2011 Microchip Technology Inc.
ACKNOWLEDGE POLLING
Initiate ID Write Cycle
Figure 3-4
ID Write Command
Send Control Byte
with R/W = 0
Condition to
Acknowledge
Send Stop
Send Start
Did Device
(ACK = 0)?
Operation
ACKNOWLEDGE
POLLING FLOW
Send
Next
for the flow diagram.
YES
NO
MCP7940X
DS25009A-page 9