Rainbow Electronics DAB-IMU-C01 - Manual (Page 12)

ADIS16250/ADIS16255
Rev. B | Page 12 of 20
DATA OUTPUT REGISTER ACCESS
The ADIS16250/ADIS16255 provide access to calibrated
rotation measurements, relative angle estimates, power supply
measurements, temperature measurements, and an auxiliary
12-bit ADC channel. This output data is continuously updating
internally, regardless of user read rates. The following bit map
describes the structure of all output data registers, except
ENDURANCE, in the ADIS16250/ADIS16255.
Table 5. Register Bit Map
MSB LSB
ND EA D13 D12 D11 D10 D9 D8
D7 D6 D5 D4 D3 D2 D1 D0
The MSB holds the new data (ND) indicator. When the output
registers are updated with new data, the ND bit goes to a 1 state.
After the output data is read, it returns to a 0 state. The EA bit is
used to indicate a system error or an alarm condition that can
result from a number of conditions, such as a power supply that
is out of the specified operating range. See the Status and
Diagnostics section for more details. The output data is either
12 bits or 14 bits in length. For all of the 12-bit output data,
Bit D13 and Bit D12 are assigned don’t care status.
The output data register map is located in Table 6 and provides
all of the necessary details for accessing each register’s data.
Table 7 displays the output coding for the GYRO_OUT register.
Figure 22 provides an example SPI read cycle for this register.
Table 6. Data Output Register Information
Name Function Address Resolution (Bits) Data Format Scale Factor (per LSB)
ENDURANCE Flash Memory Write Counter 0x01, 0x00 16 Binary 1 count
SUPPLY_OUT Power Supply Data 0x03, 0x02 12 Binary 1.8315 mV
GYRO_OUT Gyroscope Data 0x05, 0x04 14 Twos Complement 0.07326°/sec 1
AUX_ADC Auxiliary Analog Input Data 0x0B, 0x0A 12 Binary 0.6105 mV
TEMP_OUT Sensor Temperature Data 0x0D, 0x0C 12 Twos Complement 0.1453°C
ANGL_OUT Angle Output 0x0F, 0x0E 14 Binary 0.03663°
1 Assumes that the scaling is set to 320°/sec.
Table 7. Output Coding Example, GYRO_OUT 1 , 2
Rate of Rotation
±320°/sec Range ±160°/sec Range ±80°/sec Range Binary Output Hex Output Decimal
600°/sec 300°/sec 150°/sec 01 1111 1111 1111 0x1FFF 8191
320°/sec 160°/sec 80°/sec 01 0001 0001 0000 0x1110 4368
80°/sec 40°/sec 20°/sec 00 0100 0100 0100 0x0444 1092
40°/sec 20°/sec 10°/sec 00 0010 0010 0010 0x0222 546
0.07326°/sec 0.03663°/sec 0.018315°/sec 00 0000 0000 0001 0x0001 1
0°/sec 0°/sec 0°/sec 00 0000 0000 0000 0x0000 0
−0.07326°/sec −0.03663°/sec −0.018315°/sec 11 1111 1111 1111 0x3FFF −1
−40°/sec −20°/sec −10°/sec 11 1101 1101 1110 0x3DDE −546
−80°/sec −40°/sec −20°/sec 11 1011 1011 1100 0x3BBC −1092
−320°/sec −160°/sec −80°/sec 10 1110 1111 0000 0x2EF0 −4368
−600°/sec −300°/sec −150°/sec 10 0000 0000 0000 0x2000 −8192
1 Two MSBs have been masked off and are not considered in the coding.
2 Nominal sensitivity and zero offset null performance are assumed.
CS
SCLK
DIN
DOUT
ADDRESS = 000101
DATA = 1011 1101 1101 1110
NEW DATA, NO ALARM, GYRO_OUT = –40°/SECOND
W/R BIT = 0
0 607
0-
008
Figure 22. Example Read Cycle, ±320°/sec Setting