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GR716-DS-UM, May 2019, Version 1.29
395
www.cobham.com/gaisler
GR716
39.3.1
Table 522.
0x00 - SLVADDR - Slave address register
Slave Address Register
39.3.2
Table 523.
0x04 - CTRL - Control register
Control Register
31
30
10
9
0
TBA
RESERVED
SLVADDR
1
0
0x50
rw
r
rw
31
Ten-bit Address (TBA) - When this bit is set the core will interpret the value in the SLVADDR field
as a 10-bit address.
30 : 10
RESERVED
9:0
Slave address (SLVADDR) - Contains the slave I2C address.
31
5
4
3
2
1
0
RESERVED
RMOD TMOD
TV
TAV
EN
0
NR
NR
NR
NR
NR
r
rw
rw
rw
rw
rw
31 : 5
RESERVED
4
Receive Mode (RMOD) - Selects how the core handles writes:
‘0’: The slave accepts one byte and NAKs all other transfers until software has acknowledged the
received byte by reading the Receive register.
‘1’: The slave accepts one byte and keeps SCL low until software has acknowledged the received
byte by reading the Receive register.
3
Transmit Mode (TMOD) - Selects how the core handles reads:
‘0’: The slave transmits the same byte to all if the master requests more than one byte in the transfer.
The slave then NAKs all read requests as long as the Transmit Valid (TV) bit is unset.
‘1’: The slave transmits one byte and then keeps SCL low until software has acknowledged that the
byte has been transmitted by setting the Transmit Valid (TV) bit.
2
Transmit Valid (TV) - Software sets this bit to indicate that the data in the transmit register is valid.
The core automatically resets this bit when the byte has been transmitted. When this bit is ‘0’ the
core will either NAK or insert wait states on incoming read requests, depending on the Transmit
Mode (TMOD).
1
Transmit Always Valid (TAV) - When this bit is set, the core will not clear the Transmit Valid (TV)
bit when a byte has been transmitted.
0
Enable core (EN) - Enables core. When this bit is set to ‘1’ the core will react to requests to the
address set in the Slave address register. If this bit is ‘0’ the core will keep both SCL and SDA inputs
in Hi-Z state.