LS datasheet, LS circuit, LS data sheet: LSI – BIT QUADRATURE COUNTER,alldatasheet, datasheet, Datasheet search site for Electronic. LSI LS 30 available from 2 distributors. Explore LSI on Octopart: the fastest source for datasheets, pricing, specs and availability. The LSI Computer Systems LS is a CMOS, bit counter that can be programmed to operate in several View the Manufacturer’s Datasheet. Features.
|Published (Last):||2 March 2013|
|PDF File Size:||16.56 Mb|
|ePub File Size:||10.30 Mb|
|Price:||Free* [*Free Regsitration Required]|
(PDF) LS7166 Datasheet download
For more info on these features, see the datasheet. In the code below and example schematic, pins B0-B7 are used for the data bus. This c file simply loops continuously and reads values from the LS This c file contains various functions used to interface with the LS The LS communicates with a microcontroller via a bi-directional 8-bit sl7166 bus and several control bits.
Note that the code does not reset to 0 when it reaches PR. This number should be changed based on the full rotation count of the encoder in use. Note that at the end of the init function, the counter limit value is loaded into the PR register.
This is useful for motor applications, since the fixed value datashete be set to the number of pulses in a full rotation, and then whenever the count value is read, the exact position of the motor can be known no matter the amount of time that has passed since the last read.
The LS is a 24 bit quadrature counter. Since this was put in the separate function, other code won’t have to be changed, other than TRIS setups. A motor’s encoder can be connected directly to the LS, which will decode and count pulses as the encoder channels change.
The code in this document only covers divide-by-n binary quadrature mode, and for datashfet advanced features the support code will need to be modified. A chip with similar capability is the ,s7166which uses the SPI bus to communicate instead of in parallel, is discussed on separate wiki page.
LS datasheet, Pinout ,application circuits BIT QUADRATURE COUNTER
All three can be download from this zip file. The chip has several other features that can be read about in the datasheet. As mentioned above, multiple LS can be used which are connected to the same data and control lines, except for chip select, which needs to be separate for each chip. Because of this, the pic software must datashset written so that the read value of CNTR is modded by the maximum count number to find the position.
Using the LS7166 Quadrature Counter
Personal tools Log in. Dstasheet the CNTR will overflow if not reduced. Views Page Discussion View source History. The value of the PR register is loaded whenever the counter borrows downticks from 0. The LS, as mentioned above, connects to the PIC via an 8-bit data bus, 4 control bits, 2 optional control bits, and 2 optional flags.
The chip can also operate in divide-by-n mode, which loads the count register with a fixed value on rollover. There are also two pins which output flags when programmed events vatasheet, such as an overflow. For instance, if the maximum count isand Dataeheet isthen the actual position is out of Because of this, if running the motor backwards continuously counting downthe value of CNTR will always be between 0 and PR at the current position.
Note that to use thethe only steps are to setup the pins, call the init function, then call the read function to get a value. Dagasheet from ” http: The init function can be modified to utilize other special features of the chip not used here.
Using a parallel data bus, a microcontroller can simply read the current count value from the chip, allowing a project to interface with motor encoders without using any additional timers. In any motor-related application, binary counting is necessary.
The A and B inputs normally serve as quadrature inputs, like those which come catasheet a quadrature encoder like those on most motors. Note that most pins are active low, and thus must be kept at high at all times unless in use. These pins can be changed, but the data bus read and write functions will need to be changed to interface with bit lines instead of bytes. Datasheey other functions will usually not be needed unless special features are needed. Alternatively, at each read the PIC could send back the actual count value.
The following is a list of registers and the general use of each, even though they are already handled by the code written in a later section.