mc33596 Freescale Semiconductor, Inc, mc33596 Datasheet - Page 12

• Manufacturer Part Number: mc33596
• Description: Pll Tuned Uhf Receiver For Data Transfer Applications
• Manufacturer: Freescale Semiconductor, Inc

Register Access through SPI
10.3.1 Bit Definition
Two sets of configuration registers are available. They are grouped in two different banks: Bank A and
Bank B. Two bits are used to define which bank represents the state of the component.
At any time, it is possible to know what is the active bank by reading the status bit BANKS.
10.3.2 Bank Access and Register Mapping
Registers are physically mapped following a byte organization. The possible address space is 32 bytes. The
base address is specified in the command byte. This is then incremented internally to address each register,
up to the number of registers specified by N[1:0], also specified by this command byte. All registers can
then be scanned, whatever the type of transmission (read or write); however, writing to read-only bits or
registers has no effect. When the last implemented address is reached, the internal address counter
automatically loops back to the first mapped address ($00).
At any time, it is possible to write or read the content of any register of Bank A and Bank B. Register access
is defined as follows:
12
R/W
R
RR
R [A]
RR [A]
Bit Name
BANKA
Bit Name
BANKS
BANKA
BANKB
X
0
1
RESET
RSSIx
LDVS
SOE
OLS
Bit
BANKB
Direction
0
1
1
Direction
Bit can be read and written.
Bit can be read. Write has no effect on bit value.
Bit can be read. Read or write resets the value.
Bit can be read, this returns the same value as Bank A.
Bit can be read, this returns the same value as Bank A. Read or write resets the value.
R
Bank
A, B
A, B
A, B
A, B
R/W
R/W
A
Bank A is active
Bank B is active
Bank A and Bank B are active and will be used one after the other
Location
CONFIG1
CONFIG3
CONFIG3
CONFIG2
A & B
RSSI
Byte
Actions
Location
Bank A
Bank B
Bank status: indicates which register bank is active.
This bit, available in Bank A and Bank B, returns the same value.
Table 7. Access to Specific Bits
MC33596 Data Sheet, Rev. 3
RR-RR[A}
R/W-R[A}
Access
R-R[A]
R-R[A}
R/W
Comment
Available in BANKA.
Bit value is the real time status of the PLL, BANKA,
and BANKB access reflect the same value.
Bit value is the latched value of the low-voltage
detector. Read or write from any bank resets value.
SOE can be modified in BANKA. Access from BANKB
reflects BANKA value.
RSSI value is directly read from RSSI converter.
Reflected value is the same whatever the active byte.
Comment
Freescale Semiconductor