This is slightly random, but what are the fundamental differences between i2s and i2c busses? I realize i2s has three wires, but is it essentially a specialized version of i2c bus for audio applications? If so, how easy or hard do you think it would be to connect an i2s IC ADC to an i2c port of a microcontroller arm7? Of course there would have to be some modifications here and there, but as far as the difficulty, does anyone have any ideas?
Thanks, Doovieman. It would be completely pointless. The I2S but is an peer to peer unidirectional audio bus for streaming audio from a to b with no guarantees at all. The I2C bus is a bidirectional bus for moving commands and data between multiple devices with arbitration between them The I2S Bus. I2C has nothing to do with I2S. These are completely different interfaces. Find More Posts by bocka. I was laughing like hell when i read this. This is a good example of why somebody needs to do a homework even before posting a query on forum BB code is On.
Smilies are On. Forum Rules. All times are GMT. The time now is AM. Resources saved on this page: MySQL User Name. Stay logged in? Mark Forums Read.How I2C Communication Works and How To Use It with Arduino
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Quote: Originally posted by rfbrw It would be completely pointless. Send a private message to bocka. Quote: Originally posted by Doovieman It's not pointless actually. Any other thoughts? Quote: Originally posted by rfbrw If you really believe shoehorning the I2S protocol into the I2C protocol will result in a minimal solution then one can only conclude you have failed to read and understand the specifications in the links provided.
Nonetheless, every success in your endeavour. Again, the question is which is better, a or b. Snide remarks such as the one quoted above don't help and are not appreciated.
Difference between I2C and SPI ( I2C vs SPI ), you should know.
Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. It only takes a minute to sign up. As a novice electronics hobbyist, I have heard these terms and more being thrown around everywhere. At its root, I understand that they are all based on communication between devices, computers, peripherals, etc. I have a basic understanding of how all of them work, but I get confused when I see so many of them and am having difficulty understanding how they relate to each other.
What is the difference between RS and Serial? What are the core differences between all of these communication methods: reliability, cost, application, speed, hardware requirements? If you can imagine, I have all of these terms written on cards, scattered on the coffee table, and I need someone to just help me organize my understanding. Forgive me if this question is a little vague, but I really feel that is the nature of this question all together.
Serial is an umbrella word for all that is "Time Division Multiplexed", to use an expensive term. It means that the data is sent spread over time, most often one single bit after another. All the protocols you're naming are serial protocols.
It's almost as old as I am, and very simple. Most controllers have a hardware UART on board. It uses a single data line for transmitting and one for receiving data. Most often 8-bit data is transferred, as follows: 1 start bit low level8 data bits and 1 stop bit high level.
The low level start bit and high level stop bit mean that there's always a high to low transition to start the communication. That's what describes UART. No voltage level, so you can have it at 3. Note that the microcontrollers which want to communicate via UART have to agree on the transmission speed, the bit-rate, as they only have the start bits falling edge to synchronize.
That's called asynchronous communication. The data format remains the same. This can do UART, but also a synchronous protocol. In synchronous there's not only data, but also a clock transmitted. With each bit a clock pulse tells the receiver it should latch that bit. Synchronous protocols either need a higher bandwidth, like in the case of Manchester encoding, or an extra wire for the clock, like SPI and I2C.
A master sends a clock signal, and upon each clock pulse it shifts one bit out to the slave, and one bit in, coming from the slave. By using SS Slave Select signals the master can control more than one slave on the bus. There are two ways to connect multiple slave devices to one master, one is mentioned above i.
Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. It only takes a minute to sign up. The master has to provide the clock and the slave has to accept the clock. Usually, the decision is simply driven by the capabilities of the components you're trying to put together: all components are not able to be a master.
Most DACs I have seen are not able to behave as masters. MCUs are usually versatile and able to behave as both. ADCs are also, very often, able to behave as both. The reason is the following: If you need a SoC and a DAC a lot of applicationsthe SoC will typically have a complex clocking system available with fully configurable PLLs and stuffwhich makes it a good fit to be the master.
The DAC therefore don't need to be able to act as the master. This is why, typically, ADCs can also behave as masters but in that case, the clocking options are usually less flexible than with a SoC. So, to answer your question, for a typical application that uses a SoC, the SoC will be the master.
But for the other kind of devices, the same rationale can often be applied. Ideally use an external oscillator for MCLK. A MCU may not be able to derive the clock rates required without jitter . If the codec has odd audio interface modes it is often easier to configure the MCU to support them.
Difference between I2C and I2S.....
I believe in I2S there are Transmitters and Receivers. And the Master is which ever one is generating the clock. In a multiple Transmitter and Receiver scenario it gets a bit unclear. Here is what the I2S specification found here says:.
In complex systems however, there may be several transmitters and receivers, which makes it difficult to define the master. In such systems, there is usually a system master controlling digital audio data-flow between the various ICs. Transmitters then, have to generate data under the control of an external clock, and so act as a slave.I2C and SPI are both bus protocol to allow the user for short-distance, serial data transfer.
Both protocols are commonly used in electronic devices like smartphone, TV, and laptops to control the peripheral like power management chips, memory devices, input device etc.
I2C is a serial communication protocol. I2c are not only used with the single board but also used with the other external components which have connected with boards through the cables.
I2C is basically a two-wire communication protocol. It uses only two wire for the communication. In I2C, both buses are bidirectional, which means master able to send and receive the data from the slave.
The clock bus is controlled by the master but in some situations slave is also able to suppress the clock signal, but we will discuss it later. The serial peripheral interface is four wire-based full duplex communication protocol these wire generally known as MOSI master out slave inMISO master in slave outSCL a serial clock which produces by the master and SS slave select line which use to select specific slave during the communication.
SPI follows the master and slave architecture and communication is always started by the master. It is also an synchronous communication protocol because the clock is shared by master and slave. SPI is supported only multi-slave does not support multi-master and slave are selected by the slave select signal.
In SPI during the communication data is shifted out from the master and shifted into the slave vice- versa through the shift register. The course contains video lectures of Both communication protocols are the example of synchronous communication but still, both have some important difference.
I2C can be multi-master and multi-slave, which means there can be more than one master and slave attached to the I2C bus. SPI can be multi-save but does not a multi-master serial protocol, that means there can be only one master attached to SPI bus. I2C has the feature of clock stretching, that means if the slave cannot able to send fast data as fast enough then it suppresses the clock to stop the communication.
I2C is used only two wire for the communication, one wire is used for the data and the second wire is used for the clock. In I2C communication we get the acknowledgment bit after each byte. Acknowledgment bit is not supported by the SPI communication protocol.
SPI is not a multi-master communication protocol, so it does not consist the properties of arbitration. I2C is the address base bus protocol, you have to send the address of the slave for the communication.Try to learn something about everything and everything about something.
Most controllers have a hardware UART on board. It uses a single data line for transmitting and one for receiving data. Most often 8-bit data is transferred, as follows: 1 start bit low level8 data bits and 1 or 2 stop bit high level. The low level start bit and high level stop bit mean that there's always a high to low transition to start the communication.
That's what describes UART. No voltage level, so you can have it at 3. Note that the microcontrollers which want to communicate via UART have to agree on the transmission speed, the bit-rate, as they only have the start bit's falling edge to synchronize. That's called asynchronous communication. The data format remains the same. In synchronous there's not only data, but also a clock transmitted.
With each bit a clock pulse tells the receiver it should latch that bit. Synchronous protocols either need a higher bandwidth, like in the case of Manchester encoding, or an extra wire for the clock, like SPI and I2C. A master sends a clock signal, and upon each clock pulse it shifts one bit out to the slave, and one bit in, coming from the slave. By using SS Slave Select signals the master can control more than 1 slave on the bus.
There are two ways to connect multiple slave devices to one master, one is mentioned above i. That means that master and slave send data over the same wire, again controlled by the master who creates the clock signal. I2C doesn't use separate Slave Selects to select a particular device, but has addressing. After each byte receiver must send a "0" to acknowledge the reception of the byte, which the master latches with a 9th clock pulse.
If the master wants to write a byte the same process repeats: the master puts bit after bit on the bus and each time gives a clock pulse to signal that the data is ready to be read.
UART vs I2C vs SPI – Communication Protocols and Uses
If the master wants to receive data it only generates the clock pulses. The slave has to take care that the next bit is ready when the clock pulse is given.This page will help you choose.
I2C and SPI are both bus protocols that allow short-distance, serial data transfer. Both protocols are commonly used in electronic devices like smartphones, TV's and laptops to control peripherals like power management chips, input devices and DACs.
For instance, Microsoft uses I2C for the detachable keyboard on their Surface tablet. I2C allows multiple masters and slaves on the bus. On the other hand SPI can only work with one master device controlling multiple slaves. We will talk about this feature later. So with SPI, every read is also a write.
This could in theory double the speed of the bus, however, when implementing the SPI protocol we noticed that most of the time we didn't have data to send one direction. When you want to read from the device, you have to send "dummy bytes" to the device to trigger the clock signal that allows the slave to send data. Similarly, most of time the slave does not have anything to report back when you are actually sending data to the slave. With dummy packets, both protocols are essentially half-duplex.
I2C has a feature called 'clock stretching'. If the slave device cannot send the data fast enough, it can hold down the clock so data will be transfered slower.
This way, the bitrate is decreased, but the slave can keep up with the processing of the data. This feature can be very useful, since the clock rate can be high, and the slave will delay only when it needs to. The only problem is that the SoC on the Raspberry Pi has a bug in this feature.
If clock stretching is used at the wrong time, the received might be corrupt. The performance penalty is small, but as a result, all BitWizard I2C boards only work at a bus speed of kHz. The addresses on the bus are 7 bits wide. The lower bit specifies if the transaction is to be a read or a write. Write transactions have the lower bit cleared 0read transactions have the lower bit set 1. Each transaction on the bus starts with the address of the board. All BitWizard boards will ignore any transactions on the bus that do not start with their own address.
The protocols allow for changing the address in case you need more modules of the same type on one bus.It is used to communicate PCM audio data between integrated circuits in an electronic device. The bit clock pulses once for each discrete bit of data on the data lines. The bit clock frequency is the product of the sample ratethe number of bits per channel and the number of channels. So, for example, CD Audio with a sample frequency of It is typically synchronized to the falling edge of the serial clock, as the data is latched on the rising edge.
Data is signedencoded as two's complement with the MSB most significant bit first. As the impedance adaptation error, associate with the different line length, can cause difference of propagation delay between the clocks line and data line, this can result in synchronization problem between the SCK, WS and data signals, mainly at high sampling frequency and bitrate.
There is no standard interconnecting cable for this application. From Wikipedia, the free encyclopedia. For the singular, see I2 disambiguation. Philips Semiconductors. June 5, Archived from the original PDF on January 2, Analog Devices, Inc. Retrieved Clock source for the delta-sigma modulators and digital filters. It is the clock that is used by the audio codec Technical and de facto standards for wired computer buses.
PC Card ExpressCard. Interfaces are listed by their speed in the roughly ascending order, so the interface at the end of each section should be the fastest. Namespaces Article Talk. Views Read Edit View history.