MC33596_10 Datasheet, PDF (31/70 Pages) Freescale Semiconductor, Inc – PLL Tuned UHF Receiver for Data Transfer Applications

Configuration Switching
15.1.1 Direct Switch Control
The conditions to enter direct switch control are:
• Strobe pin = V_CC
• SOE bit = 0
By simply writing BANKA and BANKB, the active bank will be defined:
BANKA
X
0
1
BANKB
0 Bank A is active
1 Bank B is active
1 Not allowed in direct switch control
The defined bank is active after exiting the configuration mode, in other words, CONFB line goes high.
The direct switch control should be used when:
• When the strobe oscillator cannot be used to define the switch timing (for example, not periodic)
• When strobe pin use is not possible (no sleep mode between the two configurations)
• No automatic switching is required and MCU SPI access is possible
15.1.2 Strobe Pin Switch Control
The conditions to enter strobe pin switch control are:
• Strobe pin: controlled by MCU I/O port
• SOE bit = 0
By simply writing BANKA and BANKB, the active banks will be defined.
BANKA
X
0
1
BANKB
0 Bank A is active
1 Bank B is active
1 Bank A and Bank B are both active, configuration will toggle at each wakeup
The strobe pin will control the off/on state of the MC33596. The various available sequences are described
in the following subsections.
15.1.2.1 BANKA = X, BANKB = 0
State A
OFF
State A
OFF
Strobe Pin
If strobe pin is 1, configuration is defined by Bank A, BANKS = 1.
If strobe pin is 0, MC33596 configuration is OFF.
If a message is received during State A, current state remains State A up to end of message.
MC33596 Data Sheet, Rev. 4
Freescale Semiconductor
31