13. I2C Registers > Register Descriptions
460
Tsi578 User Manual
June 6, 2016
Integrated Device Technology
www.idt.com
13.2.21
Externally Visible I
2
C Outgoing Mailbox Register
This register is the outgoing mailbox, allowing the processor to communicate data to an external I
2
C
master. The register is R/W from the register bus, and read-only from the I
2
C bus through the slave
interface.
This register corresponds to the I
2
C peripheral addresses 0x90 through 0x93.
Register name: EXI2C_MBOX_OUT
Reset value: 0x0000_0000
Register offset: 0x1D290
Bits
0
1
2
3
4
5
6
7
00:07
DATA
08:15
DATA
16:23
DATA
24:31
DATA
Bits
Name
Description
Type
Reset
Value
0:31
DATA
Mailbox data to be transferred to an external I
2
C master.
Every write to this register by software sets the OMB_FLAG
bit in the
, indicating data is available in the outgoing
mailbox. When this register is read by an external master,
the OMB_FLAG bit is cleared, and an OMB_EMPTY
interrupt is asserted if the OMB_FLAG bit was set.
This register is read-only through the I
2
C slave interface.
Note
: A read is considered complete when the STOP
condition is seen on the I
2
C bus, and one or more bytes in
this register were read by the external master since the
preceding START condition.
R/W
0