FUNCTIONAL DEVICE OPERATION
DSI COMMANDS AND RESPONSES
addressable device and would be immune to any inadvertent
future NVM programming sequences.
Reads and writes are long-word commands only. The
command format is found in Table 21.
Table 21. Read/Write NVM Command Format
Data
Address
Command
CRC
1 1 1 1 PA3 PA2 PA1 PA0 A3 A2 A1 A0 1 0 0 1 X3 X2 X1 X0
Legend
A[3:0] = Address bits. These bits are the address of the device PA[3:0] = Program Address bits. These bits are the address that is to be
previously sent with the Initialization command. They must match programmed into the slave.
the address in the PA[3:0] field and the address stored in the
device address register.
X[3:0] = Cyclic Redundancy Check (CRC). The CRC as calculated by the
master.
READ/WRITE NVM RESPONSE
This response message is sent during the next message
following a valid Read/Write NVM command to the addressed
device. The response format is found in Table 22. The high
byte is omitted during the short-word response. No response
is generated if the command address field was $0.
Table 22. Read/Write NVM Response Format
High Byte
A3 A2 A1 A0 0 0 0 0 1 1
Legend
A[3:0] = Address bits. The slave address.
PA[3:0] = Programmed Address bits. The address that was
programmed into the NVM address bits of the slave.
Low Byte
CRC
1 1 PA3 PA2 PA1 PA0 X3 X2 X1 X0
X[3:0] = Cyclic Redundancy Check (CRC). The CRC as calculated by the
slave.
CLEAR LOGIC OUT COMMAND
The Clear Logic Out command sets the Logic Out pin to a
logic low. The compliment to this command is the Set Logic
Out. The Logic Out is also cleared at power-up or following a
Clear command. The format of the Clear Logic Out command
is shown in Table 23.
Table 23. Clear Logic Out Command Format
Data
Address
Command
CRC
–
–
–
–
–
–
–
–- A3
Legend
A[3:0] = Address bits. The address of the selected device.
A2 A1 A0 1
1
0
0 X3 X2 X1 X0
X[3:0] = Cyclic Redundancy Check (CRC). The CRC as calculated by the
master.
CLEAR LOGIC OUT RESPONSE
This response message is sent during the next message
following a valid Clear Logic Out command to the addressed
device. The response is shown in Table 24. No response is
generated if the command address field was $0.
Table 24. Clear Logic Out Response Format
High Byte
Low Byte
CRC
A3 A2 A1 A0 0 0 0 0 NV
Legend
A[3:0] = Address bits. The slave address.
BS = Bus Switch Position (1=closed).
LO = Logic out driven level.
IO[3:0] = Values at logic I/Os.
U
LO BS IO3 IO2 IO1 IO0 X3 X2 X1 X0
NV = Nonvolatile Memory Write. The value of the NV bit in the slave.
U = Undervoltage indicated true by a “1”.
X[3:0] = Cyclic Redundancy Check (CRC). The CRC as calculated by the
slave.
Analog Integrated Circuit Device Data
Freescale Semiconductor
33793
19