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I2C Master/Slave Interface
I2C external addresses
I2C external [bus] addresses are allocated as two groups of eight addresses (0000XXX
and 1111XXX), as shown in Table 334.
The general call address is for addressing all devices connected to the I2C bus. A
device can ignore this address by not issuing an acknowledgement. The meaning of
the general call address is always specified in the second byte.
I2C command interface
The I2C module converts parallel (8-bit) data to serial data and serial data to parallel
data between the NS9750 and the I2C bus, using a set of interface registers.
The primary interface register for transmitting data is the CMD_TX_DATA_REG
(write-only).
The primary interface register for receiving data is the STATUS_RX_DATA_REG
(read-only).
Slave address R/W bit Description
0000 000 0 General call address
0000 000 1 START byte (not supported in NS9750)
0000 001 X CBUS address (not supported in NS9750)
0000 010 X Reserved for different bus format
0000 011 X Reserved
0000 1xx X hs-mode master code (not supported in NS9750)
1111 1xx X Reserved
1111 0xx X 10-bit slave address
Table 334: Reserved slave addresses