AN3057

Recommendations when developing the M24LRxx application software

Doc ID 16239 Rev 4

9/15

3

Recommendations when developing the M24LRxx

application software

The application software has to take into account that a command might not be executed if

the other channel (I²C or RF) is already processing a command. The application software

should therefore check the M24LRxx busy status before sending a command.

3.1

Issuing a command through the I²C channel

3.1.1

I²C request while the RF channel is busy

If the M24LRxx is processing a command from the RF channel, no command issued on the

I²C bus will be executed, therefore none of the bytes transmitted on the I²C bus will be

application’s I²C software should include a polling loop on the RF busy state (with a timeout

limit) when issuing a command on the I²C bus. In this way, the I²C command can be

completed once the RF command under process has completed.

Figure 8.

I²C polling when the RF channel is processing a command

a.

RF command

in progress

ai17342

Start condition

Device select

with RW = 0

ACK

returned

YES

NO

Data for the

Write operation

Device select

with RW = 1

Send address

and receive ACK

First byte of the

I²C command

(with RW bit= 0) is

now decoded by the

M24LR64-R

YES

NO

Start

condition

Continue the

Write operation

Continue the

Random Read operation