SLG47503 datasheet(117/191 Pages) DIALOG

117 / 191 page

Datasheet

16-Jul-2021

CFR0011-120-00

Revision 2.0

117 of 191

SLG47502/03

Low Voltage GreenPAK Programmable

Mixed-Signal Matrix

Preliminary

00h) after valid Byte Write Command. If the next command received by the device is not a Byte Write Command, the effect of the

bit masking function will be aborted, and the I2C Byte Write Mask Register will be reset with no effect. Figure 106 shows an

example of this function.

15.4.10 Writing a New Value to the Shift Register via I2C

The new value can be written to the Shift Register if low logic level presents at the CLK input of the macrocell. Otherwise, if the

logic level at CLK input is high, the new value will be ignored.

It’s recommended to perform the following actions to write the new value to the Shift Register:

 Read Shift Register value (Old_Value);

 Write new Shift Register value;

 Read Shift Register value (New_Value) and compare it with the result of the last read (Old_Value). If New_Value isn’t equal to

the Old_Value, the writing procedure was successful. Otherwise, if New_Value is equal to the Old_Value, the content of the

Shift Register hasn’t been updated (the logic level at the CLK input is high). I2C master should perform the following steps:

 Connect the CLK input of the Shift Register to the GND (connect the corresponding matrix output to the matrix input x00);

 Analyze the LSB, if the new value to be written to the Shift Register, for example xxxx xxx(y). y is the LSB of the 8-bit value

to be written to the Shift Register.

Figure 106: Example of I2C Byte Write Bit Masking

User Actions

 Byte Write Command, Address = F6h, Data = 11110000b [sets mask bits]

 Byte Write Command, Address = 74h, Data = 10101010b [writes data with mask]

Memory Address 74h (original contents)

Memory Address 74h (new data in write command)

Memory Address F6h (mask register)

Memory Address 74h (new contents after write command)

Mask to choose bit from new

write command

Bit from original register

contents

Bit from new write command

Mask to choose bit from

original register contents

SLG47503 Datasheet(PDF) 117 Page - Dialog Semiconductor