13. I2C Registers > Register Descriptions
423
Tsi578 User Manual
June 6, 2016
Integrated Device Technology
www.idt.com
A master operation is initiated by writing this register and setting the START bit to 1. The same write
should set the WRITE, SIZE, and PADDR fields as required by the transaction. Other information for
the transaction must have been pre-loaded into the
C Master Configuration Register”
.
05:07
SIZE
Number of bytes in an I
2
C operation (read or write)
000 = 0 bytes
001 = 1 bytes
010 = 2 bytes
011 = 3 bytes
100 = 4 bytes
101 = Reserved (equivalent of 0 bytes)
110 = Reserved (equivalent of 0 bytes)
111 = Reserved (equivalent of 0 bytes)
A value of 000 should not be normally used for a Read
operation, as any device put into read mode assumes at
least one byte will be read. An exception would be the
SMBus Quick Command protocol to a device that is known
to not hold the bus following the slave address phase.
R/W
000
08:15
Reserved
Reserved
R
0
16:31
PADDR
Peripheral address for master operation
If PA_SIZE in the
C Master Configuration Register”
is 10,
then all 16 bits are used, with the most significant 8 bits
placed on I
2
C bus first, followed by the least significant 8
bits.
If PA_SIZE is 01, then only least significant 8 bits are used.
If PA_SIZE is 00, this field is not used for the transaction.
R/W
0x0000
Do not change this register while a master operation is active. The effect on the transaction
cannot be determined.
(Continued)
Bits
Name
Description
Type
Reset
Value