Ds1307 Bascom Program For Rf Software I2C And

The module comes fully assembled and pre-programmed with the current time (OK, so its MST current time).

The included Lithium coin cell battery (CR1225 41mAh) will run the module for a minimum of 9 years (17 years typical) without external 5V power.

Ds1307 Bascom Program For Rf Software I2C And

This test-bed code should give you some insight on how to interface the module to any micro-controller using our example software I2C and BCD routines.

The I2C (TWI) lines can be up to 80cm (400KHz) without any problem when the Terminator is at the end of the lines.

The IC bus and the SMBus are essentially compatible with each other.

Normally devices, both masters and slaves, are freely interchangeable between both buses.

Both buses feature addressable slaves (although specific address allocations can vary between the two).

In standard applications hardware and timing are often the same.

The way data is treated on the IC bus is to be defined by the manufacturer of the IC master and slave chips.

The difference between master and slave is that the master generates the clock pulse.

For bus timing it is important that the slowest slave should still be able to follow the masters clock.

A stop condition is a low-to-high transition of the SDA line while SCL remains high.

The length of data sent over IC is always 8 bit this includes a readwrite direction bit, so you can effectively send 7 bits every time.

A chip that acknowledges must pull down the SDA line during the acknowledge clock pulse in such a way that the SDA line is stable LOW during the HIGH period of the acknowledge related clock pulse.

The master sends a not acknowledge if data was not received correctly or if the master wishes the stop receiving.

The function of that command or word address can be found in the data sheet of the slave addressed.

After this we send the Slave address of the device we want to send a byte to.

Now you can start to send a byte (or more bytes) to this Slave address.

This because when the first AVR chips were introduced, there was no TWI yet.

With the I2CTWI lib you can use the TWI which has advantages as it require less code.

We give NACK if the last byte is read Finally we print Print Temperature:; Str ( i2ctemp ); degrees; Chr ( 13 ); Waitms 25 Loop End.

While you can use any pin for software mode I2C, when a micro has TWI hardware build in, it is advised to use the TWI hardware.

With the additional TWI slave library you can make your own slave chips.

Use 4,7k or 10 k pull up How long can the SCL, SDA line be when used with pull ups etc, etc.

Here is a Schematic for an active Termination of I2C and TWI.

We have used this Schematic for over 10 years, and have had no problems with it.