AN332
Rev. 0.8
129
5.3.1. AM/SW/LW Receiver Commands
Command 0x01. POWER_UP
Initiates the boot process to move the device from powerdown to powerup mode. The boot can occur from internal
device memory or a system controller downloaded patch. To confirm that the patch is compatible with the internal
device library revision, the library revision should be confirmed by issuing the POWER_UP command with
FUNC = 15 (query library ID). The device returns the response, including the library revision, and then moves into
powerdown mode. The device can then be placed in powerup mode by issuing the POWER_UP command with
FUNC = 1 (AM/SW/LW Receive) and the patch may be applied. See Section "7.2. Powerup from a Component
Patch" on page 234 for more information.
The POWER_UP command configures the state of ROUT (pin 13) and LOUT (pin 14) for analog audio mode and
GPO2/INT (pin 18) for interrupt operation. For the Si4731/35/37, the POWER_UP command also configures the
state of GPO3/DCLK (pin 17), DFS (pin 16), and DOUT (pin 15) for digital audio mode. The command configures
GPO2/INT interrupts (GPO2OEN) and CTS interrupts (CTSIEN). If both are enabled, GPO2/INT is driven high
during normal operation and low for a minimum of 1 µs during the interrupt. The CTSIEN bit is duplicated in the
GPO_IEN property. The command is complete when the CTS bit (and optional interrupt) is set.
Note:
To change function (e.g. AM/SW/LW RX to FM RX), issue POWER_DOWN command to stop current function; then,
issue POWER_UP to start new function.
Available in: All
Command Arguments: Two
Response Bytes: None (FUNC = 1), Seven (FUNC = 15)
Command
Bit
D7
D6
D5
D4
D3
D2
D1
D0
CMD
0
0
0
0
0
0
0
1
ARG1
CTSIEN GPO2OEN
PATCH
XOSCEN
FUNC[3:0]
ARG2
OPMODE[7:0]
ARG
Bit
Name
Function
1
7
CTSIEN
CTS Interrupt Enable.
0 = CTS interrupt disabled.
1 = CTS interrupt enabled.
1
6
GPO2OEN
GPO2 Output Enable.
0 = GPO2 output disabled (Hi-Z).
1 = GPO2 output enabled.
1
5
PATCH
Patch Enable.
0 = Boot normally
1 = Copy NVM to RAM, but do not boot. After CTS has been set, RAM may be
patched.