33784 Datasheet, PDF (21/30 Pages) Freescale Semiconductor, Inc – DSI 2.02 Sensor Interface

FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Data
Address
Command
– – – – – – – – A3 A2 A1 A0 0 1 0 1
A3 A2 A1 A0 0 1 0 1
– – A3 A2 A1 A0 0 1 0 1
Word Type
LW & ELW
SW & ESW (8-bit)
ESW (10-bit)
Response
A3 A2 A1 A0 0 0 0 0 B9 B8 B7 B6 B5 B4 B3 B2
B9 B8 B7 B6 B5 B4 B3 B2
B9 B8 B7 B6 B5 B4 B3 B2 B1 B0
Legend
A [3:0] = Address bits. The address of the selected device.
An address value of 0000 is ignored by all devices.
“–” = Don’t care bit. Can be 0 or 1.
B [9:0] = Measured value.
Figure 13. Request AN1 Command and Response Format
Word Type
LW & ELW
SW & ESW (8-bit)
ESW (10-bit)
I / O CONTROL COMMAND AND RESPONSE
This command can be used to configure the direction of
the I/O pins, and force their states if configured as outputs.
Refer to Figure 14 for the command and response format.
The response is sent during the next message following a
valid I/O Control command to the addressed device. Because
this is a long-word only command, there is no short word
response.
The direction (DR) bits are used to specify the direction
(input or output) of each pin independently. If the DR bit for a
specific I/O pin is set to 1, then that I/O pin will be an output
and the state of the level (Lx) bit will determine whether the
pin is driven high or low. If the DR bit for a specific I/O pin is
set to 0, then that pin will be an input and the Lx bit in the
command will have no affect on the state of the pin.
In the response to the I/O Control Command, the DR bits
will show the direction that the pins were programmed. The
Lx bits will have the values that were set in the command.
These values may not reflect the actual states of the pins. To
obtain the accurate states of the pins, the Request Status
Command should be used.
The 33784 will only act on the I/O Control Command if the
address bits in the command match with the address that the
device was initialized. If the addresses do not match, the
device will do nothing and no response will be generated.
Address ‘0000’ is a global command. All slaves in the
signal path will configure their I/O pins according to the state
of the data bits. No response results from the I/O control
global command.
Analog Integrated Circuit Device Data
Freescale Semiconductor
33784
21