CS4349
6.3.2
SPI Read
To read from the device, follow the procedure below while adhering to the values specified in
1.
Bring CS low.
2. The address byte on the CDIN pin must then be 10011111 (R/W = 1).
3. CDOUT pin will then output the data from the register pointed to by the MAP, which is set during the
SPI write operation.
4. If the INCR bit (see
is set to 1, keep CS low and continue providing clocks on CCLK to
read from multiple consecutive registers. Bring CS high when reading is complete.
5. If the INCR bit is set to 0 and further SPI reads from other registers are desired, it is necessary to bring
CS high, and follow the procedure detailed from step 1. If no further reads from other registers are
desired, bring CS high.
CS
CCLK
C H IP
ADDRESS
CDIN
1001111
R/W
MAP
MSB
b y te 1
CDOUT
High Impedance
DATA
LSB
b y te n
MSB
LSB MSB
LSB
C H IP
ADDRESS
1001111
R/W
MAP = Memory Address Pointer, 8 bits, MSB first
Figure 19. Control Port Timing, SPI Mode
6.4
Memory Address Pointer (MAP)
7
INCR
0
6
Reserved
0
5
Reserved
0
4
Reserved
0
3
MAP3
0
2
MAP2
0
1
MAP1
0
0
MAP0
0
6.4.1
INCR (Auto Map Increment Enable)
Default = ‘0’
0 - Disabled
1 - Enabled
6.4.2
MAP (Memory Address Pointer)
Default = ‘0000’
DS782F1
27
CIRRUS [ CIRRUS LOGIC ]
