4.4(Functional Description)-Self-test(自我测试)

4.4.1-Accelerometer self-test(加速器自我测试)
This feature permits to check the BMC150's accelerometer part functionality by applying electrostatic forces to the sensor core instead of external accelerations. By actually deflecting the seismic mass,the entire signal path of the sensor can be tested. Activating the self-test results in a static offset of the acceleration data; any external acceleration or gravitational force applied to the sensor during active self-test will be observed in the output as a superposition of both acceleration and self-test signal.
(此功能允许通过向传感器核心施加静电力而不是外部加速度来检查BMC150的加速度计部件功能。 通过实际偏转震动质量，可以测试传感器的整个信号路径。 激活自检导致加速度数据的静态偏移; 在活动自检期间施加到传感器的任何外部加速度或重力将在输出中被观察为加速度和自测试信号的叠加。。)
before the self test is enabled the g-range should be set to 8g. The self-test is activated individually for each axis by writing the proper value to the (0x32) self-test-axis bits ('01b' for x-axis,'10b' for y-axis ,'11b' for z-axis,'00b' to deactivate self-test). It is possible to control the direction of the deflection through bit (0x32) self-test-sign. The excitation occurs in negative (positive) direction if (0x32) self-test-sign='0b' ('1b'). The amplitude of the deflection has to be set high by writing (0x32) self-test-amp='1b'. After the self-test is enabled,the user should wait 50ms before interpreting the acceleration data.
(在启用自检前，g范围应设置为8g。 通过将适当的值写入（0x32）自测试轴位（x轴为'01b'，y轴为'10b'，z轴为'11b'）为每个轴单独激活自检 ，'00b'禁用自检）。 可以通过位（0x32）自检信号来控制偏转的方向。 如果（0x32）自测试符号='0b'（'1b'），则在负（正）方向上发生激励。 偏移的幅度必须通过写入（0x32）自测试amp ='1b'来设置得很高。 启用自检后，用户应在解释加速度数据前等待50ms。)
In order to ensure a proper interpretation of the sekf-test signal it is recommended to perform the self-test for both (positive and negative) directions and the to calculate the difference of the resulting acceleration values. Table 11 shows the minimum differences for each axis. The actually measured signal differences can be significantly larger.
(为了确保自我测试信号的正确解释，建议对（正和负）方向进行自检，并计算结果加速度值的差值。 表11显示每个轴的最小差异。 实际测量的信号差异可以显着更大。)
It is recommended to perform a reset of the device after a self-test has been performed. If the reset cannot be performed,the following sequence must be kept to prevent unwanted interrupt generation: disable interrupts,change parameters of interrupts ,wait for at least 50ms,enable d

esired interrupts.
(建议在执行自检后执行器件的复位。 如果无法执行复位，则必须保持以下顺序以防止产生不必要的中断：禁止中断，更改中断参数，等待至少50ms，启用所需的中断。)
4.4.2-Magnetometer self-test(地磁计自检)
BMC150 supports two self-tests modes for the magnetometer part: Normal self-test and advanced self-test.
(BMC150支持磁强计部分的两种自检模式：正常自检和高级自检。)
During normal self-test,the following verifications are performed:
(在正常的自检，下面进行验证：)
FlipCore signal path is verified by generating signals on-chip. These are processed through the signal path and the measuirement result is compared to known thresholds.
(通过在芯片上生成信号来验证FlipCore信号路径。 这些通过信号路径进行处理，并且将测量结果与已知临界值进行比较。)
FlipCore (X and Y) bondwires to ASIC are checked for connectivity.
(检查FlipCore（X和Y）连线到ASIC的连接。)
FlipCore (X and Y) bondwires and MEMS are checked for shorts.
(检查FlipCore（X和Y）键合线和MEMS的短路。)
Hall sensor connectivity is checked for open and shorted connections.
(检查霍尔传感器的连接是否断开和短路。)
Hall sensor signal path and hall sensor element offset are checked for overflow.
(检查霍尔传感器信号路径和霍尔传感器元件偏移是否溢出。)
To perform a self test,the sensor must first be put into sleep mode (OpMode ="11"). Self-test mode is then entered by setting the bit "Self test" (register 0X4C bit0) to "1".After performing self test, this bit is set back to "0". When self -test is successful,the corresponding self-test result bits are set to "1" ("X-Self-Test" register 0x42 bit0,"Y-Self-Test" register 0x44 bit0,"Z-Self-Test" register 0x46 bit0). if self-test fails for an axis,the corresponding result bit returns "0".
(要执行自检，传感器必须首先进入睡眠模式（OpMode =“11”）。 然后通过将“自检”位（寄存器0X4C位0）设置为“1”来进入自检模式。执行自检后，该位将设置为“0”。 当自检成功时，相应的自检结果位将设置为“1”（“X自检”寄存器0x42位0，“Y自检”寄存器0x44位0，“Z自检” 寄存器0x46位0）。 如果轴的自检失败，则相应的结果位返回“0”。)
Advanced self test(先进的自我测试)
Advanced self test performs a verification of the Z channel signal path functionality and sensitivity. An on-chip coil wound around the hall sen sor can be driven in both directions with a calibrated current to generate a positive or negative field of around 100 uT.
（高级自检执行Z通道信号路径功能和灵敏度的验证。 围绕霍尔传感器缠绕的片上线圈可以用校准电流在两个方向上驱动，以产生大约100uT的正或负场。）
Advanced self test is an option that is active in parallel to

the other operation modes. The only difference is that during the active measurement phase,the coil current is enabled . The recommended usage of advanced self test is the following:
（高级自检是与其他操作模式并行工作的选项。 唯一的区别是在有源测量阶段期间，线圈电流被使能。 高级自检的推荐用法如下：）
1.Set sleep mode
2.Disable X,Y axis
3.Set Z repetitions to desired level
4.Enable positive advanced self test current
5.Set forced mode,readout Z and R channel after measurement is finished
6.Enable negative advanced self test current
7.Set forced mode,readout Z and R channel after measurement is finished
8.Disable advanced self test current (this must be done manually)
9.Calculate difference between the two compensated field values. This difference should be around 200 uT with some margins.
10.Perform a soft reset of manually restore desired settings
（
1.设置睡眠模式
2.禁用X，Y轴
3.将Z重复设置为所需的电平
4.启动正前进自检电流
5.设置强制模式，测量完成后读出Z和R通道
6.负极高级自检电流
7.设置强制模式，测量完成后读出Z和R通道
8.禁用高级自检电流（必须手动完成）
9.计算两个补偿的字段值之间的差值。 这个差值应该在200 uT左右，有一些边距。
10.执行手动恢复所需设置的软复位
）
Please refer to the corresponding application note for the exact thresholds to evaluate advanced self-test.
（请参考相应的应用笔记，了解准确的临界值以评估高级自检。）
The BMC150 API/driver privided by Bosch Sensortec provides a comfortable way to perform both self-tests and to directly obtain the result without further calculations. It is recommended to use this as a reference.
（博世Sensortec授权的BMC150 API /驱动程序提供了一种舒适的方式来执行自我测试和直接获得结果，而无需进一步计算。 建议使用此作为参考。）