MicroWire Interface
7-39
MPU Public Peripherals
Figure 7–18. Behavior of a X25C02 EEPROM Read Cycle
0
0
0
0
0
0
A7
D7
UWIRE.SDI
UWIRE.SDO
UWIRE.SCLK
WIRE_NCS
1
1
A6 A5 A4 A3 A2 A1 A0
D6 D5 D4
D1 D0
On the DO line, data is generated from the
µ
Wire interface on SLCK falling
edge and read by the EEPROM interface on SCLK rising edge.
On the DI line, data is generated from the EEPROM interface on SCLK falling
edge and read by the
µ
Wire interface on SCLK falling edge.
Figure 7–19. Behavior of a XL93LC66 EEPROM Read Cycle
1
1
0
D15
UWIRE_SDI
UWIRESDO
UWIRE_SCLK
WIRE_NCS
A7 A6 A5 A4 A3 A2 A1 A0
D14 D13
D1 D0
On the DO line, data is generated from the
µ
Wire interface on SLCK falling
edge and read by the EEPROM interface on SCLK rising edge.
On the DI line, data is generated from the EEPROM interface on SCLK rising
edge and read by the
µ
Wire interface on SCLK rising edge.
7.4.3
Example of Protocol Using a Serial EEPROM (XL93LC66)
Set up the interface by writing the following values in setup 1 register (SR1):
-
CS_EDGE_RD = 1
-
CS_EDGE_WR = 0
-
CSCS_LVL = 1
-
CS_FRQ = 00
-
CS_CHK = 1
In this example, only two cycles (read and write) are described.
