This is the page for the SRF08 Ultrasonic Ranger, with I2C interface. The datasheet can be found from the Rapid Electronics website, or there is a good. The SRF08 Ultrasonic Sensor is an evolutionary step up from the SRF It requires less power to operate, has a longer range (up to 6m) and it performs its own. [an error occurred while processing this directive]. SRF08 Ultra sonic range finder . Technical Specification. Communication with the SRF08 ultrasonic.
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To the programmer the SRF08 behaves in the same way as the ubiquitous 24xx series eeprom’s, except that the I2C address is different. To get at the range information quicker datasheet. Write the 3 sequence commands in the correct order followed by the address.
Try playing with different settings until you get the result you want.
See the Changing Range and Analogue Gain sections below. If you need a different range, change it once as part of your system initialization code. If the echo is weakened then it may be the following wavefront which is detected – resulting in 8. Reading from location 0 returns the SRF08 software revision.
The sequence must be sent to the command register at location 0, which means 4 separate write transactions on the I2C bus.
The flashing is terminated immediately on sending wrf08 command the SRF See the Changing Range and Analogue Gain sections below. Consumer Shop with prices incl. It is possible to reduce the time the SRF08 listens for an echo, and hence the range, by writing to the range register at location 2.
Submit Order online now EUR Location 0 is the command register and is used to start a ranging session.
SRF08 Ultra sonic range finder
To reduce this possibility, the maximum gain can be reduced to limit the modules sensitivity to the weaker distant echo, whilst sgf08 able to detect close by objects. As soon as the ranging is complete the SRF08 will again respond to the I2C bus, so just keep reading dahasheet register until its not 0xFF anymore.
The maximum gain setting is stored only in the CPU’s RAM and is adtasheet to maximum on power-up, so if you only want do a ranging every 65mS, or longer, you can ignore the Range and Gain Registers. The datasheet can be found from the Rapid Electronics website, or there is a good resources at Robot Electronics. Some modules such as the OOPic already have pull-up resistors and you do not need to add any more. By default, the ranging lasts for 65mS, but can be changed by writing to the range register at location 2.
Creates an instance of the class. You only need one pair of resistors, not a pair for every module. Therefore, if you try to read from the SRF08 we use the software revision number a location 0 then you will get 0xFF whilst ranging. You can then read the sonar data.
(PDF) SRF08 Datasheet download
However if you wish to fire srv08 SRF08 at a faster rate than 65mS, you will definitely need to reduce the gain – see next section. A potential hazard with this is that the second ranging may pick datsheet a ddatasheet echo returning from the previous “ping”, give a false result of a close by object when there is none.
They are normally located with the bus master sff08 than the slaves. Send the “Start ranging in cm” command via I2C. This library does not use a wait statement so the micro can do something else while ranging is in progress.
The wall is large, however, and there will be reflections from a large area, with reflections from the outside being slightly behind the central reflection. Registers The SRF08 appears as a set of 36 registers. If you do so, then you will datasyeet need to change the analogue gain by writing to location 1. There are up to a further 16 results indicating echo’s from more distant objects. The echo buffer is cleared at the start of each ranging. If an echo is received within a bytes time slot then it will be set to no-zero, otherwise it will be zero.
When done, you should label the sonar with its address, however if you do forget, just power it up without sending any commands.
The beam pattern of the SRF08 is conical with datasheeh width of the beam being a function of the surface area of the transducers and is fixed.
We have examples of using the SRF08 module with a wide range of popular controllers. If a location high and low bytes is 0, then there will be no further sr08 in the rest of the registers. The sequence must be sent to the command register at location 0, which means 4 separate write transactions on the I2C bus. The beam pattern of the SRF08 is conical with the width of the beam being a function of the surface area of the transducers and is fixed.
The next two locations, 2 and 3, are the 16bit unsigned result from the latest ranging – high byte first. The datashete of this value depends on the command used, and is either the range in inches, or the range in cm or the flight time in uS. In addition to the above addresses, all sonar’s on the I2C bus will respond to address 0 – the General Broadcast address.
The SRF08 is always a slave – never a bus master. The default shipped address of the SRF08 is 0xE0. The maximum gain setting is stored only in the CPU’s RAM and is initialized to maximum on power-up, so if you only want do a ranging every 65mS, or longer, you datasheef ignore the Range and Gain Registers.
By default, this is 65mS or the equivalent datasneet 11 metres of range.
The echo buffer is cleared at the start of each ranging. You can take advantage of the fact that the SRF08 will not respond to any I2C activity whilst ranging.