MMA5224WR2 Freescale Semiconductor, MMA5224WR2 Datasheet - Page 49

• Manufacturer Part Number: MMA5224WR2
• Description: IC ACCELER 240G X-AXIS 16QFN
• Manufacturer: Freescale Semiconductor

Specifications of MMA5224WR2

• Sensing Axis: X
• Acceleration: 240 g
• Sensitivity: 0.5 g/LSB
• Package / Case: QFN-16
• Supply Voltage (max): 25 V
• Supply Current: 4 mA to 8 mA
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

4.5.4
Daisy Chain Mode can be programmed to operate in either “Simultaneous Sampling Mode”, or “Synchronous Sampling Mode”
by setting the LATENCY bit to the desired operating mode. In Simultaneous Sampling Mode, the most recent interpolated accel-
eration data sample is latched at t
acceleration data sample is latched at the time programmed in TIMESLOTA[9:0], relative to t
Table 14. Daisy Chain Programming Commands and Responses
Table 16. Valid Daisy Chain Addresses
Sensors
Freescale Semiconductor
D0
D1
A2
The device can be programmed to operate in Daisy Chain Mode by setting the TRANS_MD[1:0] bits to “Daisy Chain Mode”.
When programmed to operate in Daisy Chain Mode, the procedure below is followed:
#
Sensor Address
0
0
0
0
1
1
1
1
Short
Short
(SAdr)
CMD
Type
Daisy Chain Mode
A1
0
0
1
1
0
0
1
1
• On power-up, the device proceeds through normal PSI5 initialization as specified in
• Upon successful completion of Initialization Phase 3, including the 2 “Sensor Ready” or Sensor Defect”
• After receiving a valid address and completing the response, sync. pulses are blanked for t
• When the “Run Mode” command is received, the device responds to this command using the programmed daisy
• During initialization and Run Mode, the Sync pulse pull-down is enabled as specified in
defined time slot t
messages, responses to sync. pulses are terminated and the device waits for a PSI5 “Set Address” command
defined in
the blanking time expires, the device does not respond to any sync. pulses until a “Run Mode” command is
received, as defined in
chain time slot. All commands are then ignored, and sync pulses are responded to with acceleration data using
the following response format, regardless of the state of the relevant bits in the Device Configuration Registers:
A2
0
1
A0
0
1
0
1
0
1
0
1
– The Daisy Chain Programming command and response formats are defined in
– Valid Daisy Chain Addresses are defined in
– The response to the PSI5 Set Address command uses the pre-defined time slot t
Table 15. Daisy Chain Programming Response Code Definitions
SAdr
A1
0
1
Response Code
Error Checking
Global Address for Broadcast Message to all Sensors
Parameter
Baud Rate
RC = Error
Data Size
Time Slot
Table 14
RC = OK
A0
0
1
SAdr
F2
A2
Address of un-programmed sensor
0
TRIG
TIMESLOT_DCP
and
FC
F1
A1
0
(rising edge of Sync Pulse). In Synchronous Sampling Mode, the most recent interpolated
Table 14
Sensor Address 1
Sensor Address 2
Sensor Address 3
Sensor Address 4
Sensor Address 5
Sensor Address 6
Table
Description
F0
A0
0
15.
Section 3.1.4.3
Section 3.1.3.5
Section 3.1.3.7
Section 3.1.3.8
Programmed Sensor Address, prepended with 0s
Error during transmission of Command Message
.
Reference
and
Command Message Received Properly
Set Sensor Address (Daisy Chain)
Broadcast Message - “Run Mode”
Table
15.
Command
Definition
Table
Default time slot specified in
16.
Low Baud Rate: 125 kBaud
Bus Switch Control
Even Parity
10-bit data
CLOSED
CLOSED
CLOSED
OPEN
OPEN
OPEN
Value
N/A
N/A
Response (OK)
RC
OK
OK
TRIG
Table 16
(rising edge of Sync Pulse).
0x000
0x1E1
0x1E2
Varies
Value
SAdr
Section 4.4
RD1
Section
TIMESLOT_DCP
Section
Default Time Slot
DC_BLANKING
t
t
t
t
t
t
TIMESLOT_DC1
TIMESLOT_DC2
TIMESLOT_DC3
TIMESLOT_DC1
TIMESLOT_DC2
TIMESLOT_DC3
5.4.
Response (Error)
Error
Error
RC
3.1.3.3.
using a pre-
N/A
N/A
MMA52xxWR
.
. Once
ErrN
ErrN
RD1
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