Datasheet

 2008-2013 Microchip Technology Inc. DS22096B-page 53
MCP453X/455X/463X/465X
7.2 Data Byte
Only the Read Command and the Write Command
have Data Byte(s).
The Write command concatenates the 8-bits of the
Data Byte with the one data bit (D8) contained in the
Command Byte to form 9-bits of data (D8:D0). The
Command Byte format supports up to 9-bits of data so
that the 8-bit resistor network can be set to Full-Scale
(100h or greater). This allows wiper connections to
Terminal A and to Terminal B. The D9 bit is currently
unused.
7.3 Error Condition
If the four address bits received (AD3:AD0) and the two
command bits received (C1:C0) are a valid combina-
tion, the MCP4XXX will Acknowledge the I
2
C bus.
If the address bits and command bits are an invalid
combination, then the MCP4XXX will Not Acknowledge
the I
2
C bus.
Once an error condition has occurred, any following
commands are ignored until the I
2
C bus is reset with a
Start Condition.
7.3.1 ABORTING A TRANSMISSION
A Restart or Stop condition in the expected data bit
position will abort the current command sequence and
data will not be written to the MCP4XXX.
TABLE 7-3: COMMANDS
Command Name # of Bits
High
Voltage
(V
IHH
) on
HVC pin?
Write Data 29 —
Read Data 29 —
Increment Wiper 20 —
Decrement Wiper 20 —
High Voltage Write Data 29 Yes
High Voltage Read Data 29 Yes
High Voltage Increment Wiper 20 Yes
High Voltage Decrement Wiper 20 Yes