AN645 S i477 X P ROGRAMMING G UIDE 1. Introduction This document provides an overview of the programming requirements for the Si477x AM/FM receiver with support for an external IBOC HD demodulator. The hardware control interface and software commands are detailed along with several examples of the required steps to configure the device for various modes of operation. Table 1 provides a programming guide cross-reference for each Si477x part released by Silicon Labs to date. This programming guide focuses on the Si477x-A20 release. Table 1. Si477x Programming Guide and Firmware Revisions Part # Si477x-A20 Part Revision FMRX Component AMRX Component Programming Guide Revision 2.0 10.1.0 9.1.0 0.2 2. Overview This family of products is programmed using commands and responses. To perform an action, the system controller writes a command byte and associated arguments, which cause the device to execute the given command. The device will, in turn, provide a response depending on the type of command that was sent. The device has a slave control interface that allows the system controller to send commands to and receive responses from the device using 2-wire mode (I2C compatible). 3. Terminology CTS—Clear to send Complete NVM—Non-volatile internal device memory Device—Refers to the AM/FM Receiver System Controller—Refers to the system microcontroller CMD—Command byte ARGn—Argument byte (n = 1 to 7) STATUS—Status byte RESPn—Response byte (n = 1 to 15) STC—Seek/Tune Rev. 0.3 8/13 Copyright © 2012 by Silicon Laboratories AN645 AN645 4. Control Interface The Si477x provides an I2C-compatible, 2-wire control interface. In powerdown mode, all circuitry is disabled except for the device control interface. The device comes out of powerdown mode when the POWER_UP command is written to the command register. Once in powerup mode, the device accepts additional commands such as tuning. The device will not accept commands while in powerdown mode, with the exception of the powerup command. If the system controller writes a command other than POWER_UP when in powerdown mode, the device does not respond, and the command is ignored. Setting the RSTB pin low places the device in reset mode. In reset mode, all circuitry is disabled including the device control interface; registers are set to their default settings, and the control bus is disabled. 4.1. 2-Wire Control Interface Figure 1 and Figure 2 show the 2-wire control interface read and write timing parameters and diagrams, respectively. Refer to the Si477x data sheet for timing parameter values. SCL 70% SDA 70% tSU:STA tHD:STA tLOW START tr:IN tHIGH tr:IN tf:IN tSP tSU:STO tBUF 30% 30% tHD:DAT tSU:DAT tf:IN, tf:OUT tPD:DAT STOP START Figure 1. I2C Control Interface Read and Write Timing Parameters SCL SDA (Write) Command 7-0 A6-A0, 0 START SDA (Read) ADDRESS + R/W ACK ADDRESS + R/W ACK Status 7-0 A6-A0, 1 START DATA Arg1 7-0 ACK DATA DATA Rev. 0.3 STOP ACK STOP Response 7-0 ACK DATA Figure 2. I2C Control Interface Read and Write Timing Diagram 2 ACK AN645 Two-wire bus mode uses the SCL and SDA pins for signaling. A transaction begins with the START condition, which occurs when SDA falls while SCL is high. Next, the system controller drives an 8-bit control word serially on SDA, which is captured by the device on rising edges of SCL. The control word consists of a seven-bit device address followed by a read/write bit (read = 1, write = 0). The device acknowledges the control word by driving SDA low on the next falling edge of SCL. For write operations, the system controller next sends a data byte on SDA, which is captured by the device on rising edges of SCL. The device acknowledges each data byte by driving SDA low for one cycle on the next falling edge of SCL. For each write transaction, the first byte is a command and the following bytes are arguments. For read operations, after the device has acknowledged the control byte, it will drive an eight-bit data byte on SDA, changing the state of SDA on the falling edges of SCL. The system controller acknowledges each data byte by driving SDA low for one cycle on the next falling edge of SCL. If a data byte is not acknowledged by the system controller, the transaction will end. For each read transaction, the first byte is the status byte and the following bytes are the response data from the receiver. A 2-wire transaction ends with the STOP condition, which occurs when SDA rises while SCL is high. Rev. 0.3 3 AN645 5. Powerup and Powerdown There are two procedures for powering up a receiver to move it from powerdown mode to the powerup mode. The first is a powerup from internal receiver memory. The second is a powerup from a firmware component patch that is stored in system controller memory. Patches can be applied to a firmware component by the system controller via a download mechanism to address field issues, errata, or adjust device behavior. Patches are encrypted and unique to a particular device firmware version, cannot be generated by customers, and can be used to replace a portion of the component (to address errata, for example) or to download an entirely new component. The user must verify that the device contains the correct base firmware to support the patch as described later in this section. It is possible to configure the receiver for operation with a crystal or an external clock. Refer to Table 2 below. Table 2. Clocking Options Frequency (MHz) Crystal External Clock 37.209375 X X 36.4 X X 37.8 X X Powerup from device memory is described in section “5.1. Powerup from Internal Memory” using a patch is described in section “5.2. Powerup from a Patch”. 4 Rev. 0.3 AN645 5.1. Powerup from Internal Memory START 1. Supply VA, VD, VIO1 and VIO2 while keeping the RSTB =0 2. After a minimum of 100uS, set RSTB = 1 3. After a minimum of 100uS, continue to the next step 4. Send the POWER_UP command for the desired function (AM, FM) 5. Commence normal operation 6. Send POWER_DOWN command 1. Supply VA, VD, VIO1 and VIO2 while keeping the RSTB=0. Power supplies may be sequenced in any order. 2. After a minimum of 100 µs, set RSTB=1. 3. After a minimum of 100 µs, continue to the next step. 4. Send the POWER_UP command for the desired function (AM, FM). Example (with crystal 36.4 MHz, FM function): Rev. 0.3 5 AN645 POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0xF7 Normal operation. ARG2 0x28 Crystal load capacitance=11.08pF ARG3 0x07 Disables CTS interrupt, crystal bias=7. ARG4 0x12 FM function, crystal frequency 36.4 MHz. ARG5 0x11 Crystal, receiver 1. STATUS →0x80 Example (with external clock 36.4 MHz, FM function): POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x00 Crystal load capacitance=0pF ARG3 0x03 Disables CTS interrupt, crystal bias = 3. ARG4 0x12 FM function, crystal frequency 36.4 MHz. ARG5 0x12 External clock, receiver. STATUS →0x80 5. The device is ready to commence normal operation and accept additional commands. Refer to Figure 3. Figure 3. Powerup Timing 6. If desired, send the POWER_DOWN command. 6 Rev. 0.3 AN645 Example: POWER_DOWN Command Action Data Description CMD 0x11 POWER_DOWN ARG1 0x00 Disable oscillator (ARG1 may be omitted with the same result) STATUS →0x80 CTS=1 7. It is now possible to move to the powerup state by returning to step 4. Rev. 0.3 7 AN645 5.2. Powerup from a Patch START A 1. Supply VA, VD, VIO1 and VIO2 while keeping the RSTB =0 4. Send the POWER_UP command for the desired function (AM, FM) 2. After a minimum of 100uS, set RSTB = 1 5. Send PART_INFO command. 3. After a minimum of 100uS, continue to the next step 6. Send POWER_DOWN command. B Verify Firmware and ROM revision? A B 7. Send the POWER_UP command with boot loader function 8. Send patch data. 9. Send the POWER_UP command for the desired function (AM, FM) 10. Commence normal operation. 11. Send POWER_DOWN command. 8 Rev. 0.3 AN645 1. Supply VA, VD, VI01 and VI02 while keeping the RSTB=0. Power supplies may be sequenced in any order. 2. After a minimum of 100 µs, set RSTB=1. 3. After a minimum of 100 µs, proceed to the next step. 4. (Optional – step 1 of 3 to verify part firmware revision and ROM revision.) Both part firmware revision and ROM revision must be compatible with a partial patch and ROM revision must be compatible with a full patch. Send the POWER_UP command for the desired function (AM, FM). Example (with crystal 36.4 MHz, FM function): POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x28 Crystal load capacitance = 11.08 pF. ARG3 0x07 Disables CTS interrupt, crystal bias=7. ARG4 0x12 FM function, crystal frequency 36.4 MHz. ARG5 0x11 Crystal, receiver 1. STATUS →0x80 Example (with external clock 36.4 MHz, FM function): POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x00 Crystal load capacitance = 0 pF. ARG3 0x03 Disables CTS interrupt, crystal bias=3. ARG4 0x12 FM function, clock frequency 36.4 MHz. ARG5 0x12 External clock, receiver 1. STATUS →0x80 5. (Optional—step 2 of 3 to verify part firmware revision and ROM revision). Verify part firmware revision and ROM revision. Send the PART_INFO command. Rev. 0.3 9 AN645 Example: PART_INFO Command Action Data Description CMD 0x02 PART_INFO STATUS →0x80 CTS=1 RESP1 →0x06 Chip revision, 6 RESP2 →0x43 Part number, Si47+ last two digits, 0x4D=77, or Si4777 RESP3 →0x02 Firmware major revision=1 RESP4 →0x00 Firmware minor revision=0 RESP5 →0x00 Firmware build version=0 RESP6 →0x00 Reserved, values will vary. RESP7 →0x00 Reserved, values will vary. RSP8 →0x04 ROM ID RESP9 →0x00 Reserved, values will vary. In this example, the part revision is 2.0.0 and the ROM ID is 4. Ensure that partial patches received from Silicon Labs are intended for use with the part firmware revision and ROM, and that full patches are intended for use with the ROM ID as shown in Table 3. It is possible to verify the FM and AM component firmware revisions with the FUNC_INFO command, however, this is not necessary because there is always a unique mapping of component revision to part revision. Table 3. Si477x Firmware and ROM Compatibility Part # Si477x-A20 Firmware Revision ROM ID 2.0 5 FM Revision 10.1.0 AM Revision 9.1.0 6. (Optional—step 3 of 3 to verify part firmware revision and ROM revision.) Send the POWER_DOWN command. This step is required before proceeding with the patching procedure if steps 4 and 5 have been followed. Example POWER_DOWN Command Action Data Description CMD 0x11 POWER_DOWN ARG1 0x00 Disable oscillator (ARG1 may be omitted with the same result) STATUS →0x80 CTS=1 7. Send the POWER_UP command for boot loader function. Example (with crystal 36.4 MHz, boot loader function): 10 Rev. 0.3 AN645 POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x28 Crystal load capacitance = 11.08 pF. ARG3 0x07 Disables CTS interrupt, crystal bias=7. ARG4 0x02 Boot loader function, crystal frequency 36.4 MHz. ARG5 0x11 Crystal, receiver 1. STATUS →0x80 Example (with external clock 36.4 MHz, boot loader function): POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x00 Crystal load capacitance = 0 pF. ARG3 0x03 Disables CTS interrupt, crystal bias=3. ARG4 0x02 Boot loader function, clock frequency 36.4 MHz. ARG5 0x12 External clock, receiver 1. STATUS →0x80 8. Send the patch data. The patch file provided by Silicon Labs typically has a .csg extension. The system controller must send each line of 8 bytes, wait for a CTS, then send the next line of 8 bytes, etc., until the entire patch has been sent. An example showing the first few lines and final line of a patch file is shown below. Note that the “#” character indicates a comment and the patch file indicates the required ROM ID for a partial or full download. If the checksum fails, the part issues an error code, ERR (bit 6 of the STATUS byte received after each 8-byte transfer), and halts. The part must be reset to recover from this error condition. The following is an example of a patch file: # COPYRIGHT=2011 Silicon Laboratories, Inc. # GENERATED=13:53 May 23 2011 # ROMID=0x04 # PATCHID=0x228C # REQUIRES=NONE # SIZE=8272 # FUNCTION=FMRX # MAJOR=8 # MINOR=0 # BUILD=8 Rev. 0.3 11 AN645 # CRCT=0x81CF # CRCM=0x0A6C # CRCP=0xEC8D # CRCX=0x66EE # CRCY=0x6381 # CRCZ=0xA805 0x04,0x11,0x81,0xCF,0x00,0x00,0x0D,0xC6 0x05,0xAE,0xE1,0xBD,0xB4,0x90,0x07,0x33 0x06,0xD9,0x3D,0x11,0xF7,0x25,0xCB,0x06 0x17,0x7A,0xF8,0xD0,0x71,0x10,0x3F,0xB7 0x1F,0xBF,0xFF,0x7E,0x42,0xE7,0x53,0x05 … [Additional Lines] … 0x08,0x21,0xAB,0xB5,0xF1,0x7A,0xD6,0x5A 0x08,0x10,0x0E,0x9E,0x3B,0xD1,0x01,0xF4 0x08,0xBF,0x8D,0x94,0xB0,0x2D,0xCF,0xFF 0x05,0x8D,0xB1,0x22,0xF2,0x8D,0x22,0x8C # END 12 Rev. 0.3 AN645 Example: First line of the patch file example Action Data CMD 0x04 ARG1 0x11 ARG2 0x81 ARG3 0xCF ARG4 0x00 ARG5 0x00 ARG6 0x0D ARG7 0xC6 STATUS →0x80 Description Second line of the patch file example CMD 0x05 ARG1 0xAE ARG2 0xE1 ARG3 0xBD ARG4 0xB4 ARG5 0x90 ARG6 0x07 ARG7 0x33 STATUS →0x80 9. Send the POWER_UP command for the desired function (AM, FM). Example (with crystal 36.4 MHz, FM function): POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x28 Crystal load capacitance = 11.08 pF. ARG3 0x07 Disables CTS interrupt, crystal bias=3. ARG4 0x12 FM function, crystal frequency 36.4 Hz. ARG5 0x11 Crystal, receiver 1. STATUS →0x80 Example (with external clock 36.4 MHz, FM function): Rev. 0.3 13 AN645 POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x00 Crystal load capacitance = 0 pF. ARG3 0x03 Disables CTS interrupt, crystal bias=3. ARG4 0x12 FM function, crystal frequency 36.4 MHz. ARG5 0x12 External clock, receiver 1. STATUS →0x80 10. The device is ready to commence normal operation and accept additional commands. 11. If desired, send the POWER_DOWN command. Example: POWER_DOWN Command Action Data Description CMD 0x11 POWER_DOWN ARG1 0x00 Disable oscillator (ARG1 may be omitted with the same result) STATUS →0x80 CTS=1 12. It is now possible to move to the powerup state by returning to step 7. 14 Rev. 0.3 AN645 6. Digital Audio Interface The digital audio interface operates in slave mode and supports 5 different audio data formats: 2 I S Audio Left-Justified Audio Right-Justified Audio DSP Audio DSP Left-Justified Audio In I2S mode, the MSB is captured on the second rising edge of DCLK following each DFS transition. The remaining bits of the word are sent in order down to the LSB. The Left Channel is transferred first when the DFS is low, and the Right Channel is transferred when the DFS is high. In left-justified mode, the MSB is captured on the first rising edge of DCLK following each DFS transition. The remaining bits of the word are sent in order down to the LSB. The Left Channel is transferred first when the DFS is high, and the Right Channel is transferred when the DFS is low. In right-justified format, by default, the LSB is captured on the last rising edge of DCLK in each valid DFS interval. The left channel is transferred first when the DFS is high, and the right channel is transferred when the DFS is low. In DSP format, the DFS becomes a pulse with a width of one DCLK period. The left channel is transferred first, followed right away by the right channel. There are two options in transferring the digital audio data in DSP format; the MSB of the left channel can be transferred on the first rising edge of DCLK following the DFS pulse (leftjustified DSP format) or on the second rising edge. In all audio formats, depending on the word size, DCLK frequency, and sample rates, there may be unused DCLK cycles after the LSB of each word before the next DFS transition and MSB of the next word. In addition, the user can configure the MSB to be captured on the falling edge of DCLK via properties. The number of audio bits can be configured for 8, 16, 20, or 24 bits. Rev. 0.3 15 AN645 DCLK LEFT CHANNEL DFS RIGHT CHANNEL I2S 1 DCLK DOUT 1 1 DCLK 2 n-2 3 n-1 MSB n 1 LSB MSB 2 n-2 3 n-1 n LSB Figure 4. I2S Audio Format DCLK DFS DOUT LEFT CHANNEL 1 2 3 n-2 RIGHT CHANNEL n-1 MSB n 1 LSB MSB 2 n-2 3 n-1 n LSB Figure 5. Left-Justified Audio Format DCLK DFS DOUT LEFT CHANNEL 1 MSB 2 3 RIGHT CHANNEL n-2 n-1 n 1 LSB MSB Figure 6. Right-Justified Audio Format 16 Rev. 0.3 2 3 n-2 n-1 n LSB AN645 DCLK DFS LEFT CHANNEL 1 DCLK DOUT (MSB at 2nd rising edge) 1 2 3 n-2 RIGHT CHANNEL n-1 MSB n 1 LSB MSB 2 3 n-2 n-1 n LSB Figure 7. DSP Audio Format DCLK DFS RIGHT CHANNEL LEFT CHANNEL DOUT (MSB at 1st rising edge) 1 MSB 2 3 n-2 n-1 n 1 LSB MSB 2 3 n-2 n-1 n LSB Figure 8. DSP Left-Justified Audio Format Rev. 0.3 17 AN645 7. Digital ZIF I/Q Interface The digital ZIF I/Q output can provide the down converted channelized AM/FM signal at baseband to a third-party processor for AM/FM HD radio processor for IBOC signal processing (Si4777 only). The Si4777 provide a 500 kHz BW signal for FM IBOC signal processing and a 30 kHz BW signal for AM IBOC signal processing. The ZIF I/Q 4pin interface consists of two data serial lines containing I and Q data, a bit clock, and a word frame for each data sample. The interface operates in master mode and supports five different data formats: I2S ZIF Left-Justified ZIF Right-Justified ZIF DSP ZIF DSP Left-Justified ZIF Table 4. ZIF I/Q Interface Description Pin Description IOUT 16-bit baseband I word QOUT 16-bit baseband Q word IQFS Word frame sync for I and Q words IQCLK Bit clock for I and Q data 7.1. ZIF I/Q Data Formats In I2S format, by default, the MSB is captured on the second rising edge of IQCLK following each IQFS transition. The remaining bits of the word are sent in order, down to the LSB. In Left-Justified format, by default, the MSB is captured on the first rising edge of IQCLK following each IQFS transition. The remaining bits of the word are sent in order, down to the LSB. In Right-Justified format, by default, the LSB is captured on the last rising edge of IQCLK in each valid IQFS interval. In DSP format, the IQFS becomes a pulse with a width of 1 IQCLK period. There are two options in transferring the digital baseband I/Q data in DSP format: the MSB of I and Q data can be transferred on the first rising edge of IQCLK following the IQFS pulse (left-justified DSP format) or on the second rising edge. In all data formats, depending on the word size, IQCLK frequency, and sample rates, there may be unused IQCLK cycles after the LSB of each word before the next IQFS transition and MSB of the next word. In addition, if preferred, the user can configure the MSB to be captured on the falling edge of IQCLK via properties. The number of baseband I/Q bits is configured for 16 bits. 18 Rev. 0.3 AN645 IQCLK Sample n IQFS Sample n+1 1 IQCLK 1 IQCLK 1 IOUT 2 n-2 3 n-1 MSB QOUT 1 2 n-2 3 n 1 LSB MSB n 1 LSB MSB n-1 MSB 2 n-2 3 n-1 n LSB 2 n-2 3 n-1 n LSB Figure 9. I2S ZIF Format IQCLK IQFS IOUT Sample n 1 2 3 Sample n+1 n-2 n-1 MSB QOUT 1 2 3 n-2 n-1 MSB n 1 LSB MSB n 1 LSB MSB 2 n-2 3 n-1 n LSB 2 n-2 3 n-1 n LSB Figure 10. Left-Justified ZIF Format IQCLK IQFS IOUT Sample n 1 2 3 Sample n+1 n-2 n-1 MSB QOUT 1 MSB 2 3 n-2 n-1 n 1 LSB MSB n 1 LSB MSB 2 3 n-2 n-1 n LSB 2 3 n-2 n-1 n LSB Figure 11. Right-Justified ZIF Format Rev. 0.3 19 AN645 IQCLK IQFS Sample n 1 IQCLK IOUT (MSB at 2nd rising edge) 1 2 3 Sample n+1 n-2 n-1 MSB n 1 LSB MSB 2 3 QOUT (MSB at 2nd rising edge) 1 2 3 n-1 Sample n+1 n-2 n-1 MSB n 1 LSB MSB 2 n-2 3 n-1 IQCLK IQFS Sample n 1 2 3 Sample n+1 n-2 n-1 MSB n 1 LSB MSB 2 3 1 MSB 2 3 n-1 n Sample n+1 n-2 n-1 n LSB 1 2 3 MSB Figure 13. DSP Left-Justified ZIF Format 20 n-2 LSB Sample n QOUT (MSB at 1st rising edge) Rev. 0.3 n LSB Figure 12. DSP ZIF Format IOUT (MSB at 1st rising edge) n LSB Sample n 1 IQCLK n-2 n-2 n-1 n LSB AN645 7.2. ZIF I/Q Sample Rates and Clocking Requirements The device supports a number of industry-standard sampling rates including 650, 675, and 744.1875 kHz. The external crystal and/or reference clock frequency must be the following to support the following ZIF I/Q samples rates for interface to an HD radio demodulator/decoder or DSP. Table 5. Crystal/Reference Clock Frequency Requirements for the ZIF I/Q Sample Rates and Bit Clock Rates Supported RCLK/XTAL Frequency (MHz) 36.4000 37.8000 37.209375 IQFS ZIF I/Q Sample Rate (kHz) IQCLK I/Q Bit Clock (MHz) Broadcast Reception Modes 650.0000 10.4000 AM/FM HD-Radio 325.0000 5.2000 FM Analog 40.6250 2.2750 AM Analog 675.0000 10.8000 AM/FM HD-Radio 337.5000 5.4000 FM Analog 42.1875 2.3625 AM Analog 744.1875 14.88375 AM/FM HD-Radio 372.0938 7.4419 FM Analog 46.5117 1.8605 AM Analog Sample n 1 2 3 Sample n+1 n-2 n-1 MSB n 1 LSB MSB 2 MSB 2 3 n-1 n LSB Sample n 1 n-2 3 Sample n+1 n-2 n-1 n LSB Rev. 0.3 1 MSB 2 3 n-2 n-1 n LSB 21 AN645 8. Timing 8.1. Command and Property Timing When the user reads a response over the I2C bus, the first 8 bits returned are the STATUS register. Bit 7 of the STATUS register is the CTS bit (Clear to Send). When CTS is 1, it indicates that the chip is ready to receive a new command. Seek and Tune commands may take longer to complete than most other commands, so they also use the STC bit (Seek/Tune Complete) to indicate they have completed. STC is bit 0 of the STATUS register. When the user sends any command, the CTS bit will immediately reset to 0. CTS will remain 0 while the chip processes the command. When the chip is finished processing the command, the CTS bit will be set back to 1. Before sending another command, the user may poll CTS by reading the first byte of response until CTS=1. If the user has enabled the optional CTS interrupt, then the INTB pin will pulse low immediately after CTS has been set to 1, to notify the user that the previous command has completed. For information on how to enable the CTS interrupt, see the INT_CTL_ENABLE property and CTSIEN bit in the arguments for the POWER_UP command. The commands for seek and tune (FM_TUNE_FREQ, FM_SEEK_START, etc.) will cause CTS to reset to 0 for a short time, but they will set CTS back to 1 after the seek or tune has started. The seek or tune is progressing even though CTS has been set back to 1. Although the user is free to send another command at this time, it is highly recommended to wait until the STC (Seek/Tune Complete) bit has been set to 1 before sending another command. The only exception is the AM/FM/WB_RSQ_STATUS command, which may be sent at any time because it can be used to cancel the seek/tune in progress and check the status of which station seek is currently on. When the seek/tune completes, the STC bit will be set to 1. The user may poll STC by reading the first byte of response until STC=1. If the user has enabled the optional STC interrupt, then the INTB pin will pulse low immediately after STC has been set to 1, to notify the user that the seek or tune has completed. For information on how to enable the STC interrupt, see the INT_CTL_ENABLE property. After the seek or tune has completed, the user may acknowledge the completion by sending the AM/FM/ WB_RSQ_STATUS command with the STCACK bit set to 1. This will reset the STC bit back to 0. After this, the user may send another seek or tune command. Alternatively a new seek or tune command will also clear the STC bit when it begins. Figure 14 shows a seek or tune command with the optional CTS and STC interrupts enabled. The timing parameters are shown in Table 6. Control Bus Command Command FM_TUNE_FREQ FM_RSQ_STATUS CTS Bit STC Bit INTB tINT tCTS tSTC Figure 14. CTS and STC Timing Model 22 Rev. 0.3 AN645 Table 6. Command Timing Parameters for Common Commands Command tCTS tSTC tINT POWER_UP 100 ms — 3 µs POWER_DOWN <1000 ms — 3 µs FUNC_INFO <200 µs — 3 µs SET_PROPERTY <200 µs — 3 µs GET_PROPERTY <200 µs — 3 µs GET_INT_STATUS <200 µs — 3 µs AGC_STATUS <200 µs — 3 µs DIG_AUDIO_PIN_CFG <200 µs — 3 µs ZIF_PIN_CFG <200 µs — 3 µs GPIO_CTL_PIN_CFG <200 µs — 3 µs ANA_AUDIO_PIN_CFG <200 µs — 3 µs Table 7. Command Timing Parameters for FM Receiver Command tCTS tSTC tINT FM_TUNE_FREQ <200 µs 21 ms 3 µs FM_TUNE_FREQ (fast tune) <200 µs 5 ms 3 µs FM_SEEK_START <200 µs See Note below. 3 µs FM_RSQ_STATUS <200 µs — 3 µs FM_ACF_STATUS <200 µs — 3 µs FM_RDS_STATUS <200 µs — 3 µs FM_RDS_BLOCKCOUNT <200 µs — 3 µs *Note: tSTC is seek time per channel. Total seek time depends on bandwidth, channel spacing, and number of channels to next valid channel. Worst case seek time complete for FM_SEEK_START is – FM_SEEK_BAND_BOTTOM FM_SEEK_BAND_TOP ------------------------------------------------------------------------------------------------------------------------------------------------- + 1 t STC FM_SEEK_FREQ_SPACING The seek time will require an additional 26 ms for channel spacings other than 200 kHz Rev. 0.3 23 AN645 Table 8. Command Timing Parameters for AM Receiver Command tCTS tSTC tINT AM_TUNE_FREQ 100 µs 40 ms 3 µs AM_SEEK_START 100 µs See Note below. 3 µs AM_RSQ_STATUS 100 µs — 3 µs AM_ACF_STATUS 100 µs — 3 µs *Note: tSTC is seek time per channel. Total seek time depends on bandwidth, channel spacing, and number of channels to next valid channel. 8.2. Fast Tune Timing The timing diagram for fast tune is shown in Figure 15. F1 } F1 F2 F2 Audio Audio T2 T1 T1 Fast Tune command issued Fast Tune Initiated T1 ~ 0.5 ms T2 ~ 1 ms Figure 15. Fast Tune Timing Diagram 24 Rev. 0.3 AN645 9. Commands and Properties 9.1. Common Commands and Properties The following properties and commands are common to all receiver modes. Table 9. Common Receiver Command Summary Number Name Summary 0x01 POWER_UP Power-up device and mode selection. Modes include operational function (AM, FM) and audio interface configuration. 0x02 PART_INFO Returns the part information of the device. 0x11 POWER_DOWN 0x12 FUNC_INFO 0x13 SET_PROPERTY Sets the value of a property. 0x14 GET_PROPERTY Retrieve a property's value. 0x15 GET_INT_STATUS Read interrupt status bits. 0x17 AGC_STATUS 0x18 DIG_AUDIO_PIN_CFG 0x19 ZIF_PIN_CFG 0x1A GPIO_CTL_PIN_CFG 0x1B ANA_AUDIO_PIN_CFG 0x1C INTB_PIN_CFG Power-down the device. Returns the firmware revision and patch revision. Reports the status of the AGC. Configures the digital audio pins. Configures the digital I/Q pins. (Si4777 only) Configures GPIO1 and GPIO2 pins. Configures the analog audio pins. Configures behavior of INTB and A1 pins. Table 10. Common Receiver Property Summary Number Name Default 0x0000 INT_CTL_ENABLE 0x0200 DIGITAL_IO_INPUT_SAMPLE_RATE 0x0201 DIGITAL_IO_INPUT_FORMAT 0x0202 DIGITAL_IO_OUTPUT_SAMPLE_RATE 0x0203 DIGITAL_IO_OUTPUT_FORMAT 0x0000 0 Summary Interrupt enable property. 0xBB80 Sets the digital input sample rate in units of 48000 Hz. (Si4777 only) 0x3600 13824 Configures digital audio input format. (Si4777 only) 0xBB80 Sets the digital output sample rate in units of 48000 Hz. 0x3600 13824 Rev. 0.3 Configures digital audio output format. 25 AN645 Table 10. Common Receiver Property Summary (Continued) Number Name Default 0x0300 AUDIO_ANALOG_VOLUME 0x0301 AUDIO_MUTE 0x0600 ZIF_OUTPUT_CFG 0x003F 63 0x0000 0 0X0801 2049 Summary Sets the analog audio volume. Audio mute property. Enables or disables ZIF and configures ZIF interface format (Si4777only). Table 11. Status Response for the FM Receiver 26 Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Bit Name Function 7 CTS Clear to Send. 0 = Wait before sending next command. 1 = Clear to send next command. 6 ERR Error. 0 = No error. 1 = Error. 5:4 Reserved Values may vary. 3 RSQINT Received Signal Quality Interrupt. 0 = Received Signal Quality measurement has not been triggered. 1 = Received Signal Quality measurement has been triggered. 2 RDSINT Radio Data System Interrupt. 0 = Radio data system interrupt has not been triggered. 1 = Radio data system interrupt has been triggered. 1 ACFINT Automatically Controlled Features Interrupt. 0 = ACF measurement has not been triggered. 1 = ACF measurement has been triggered. 0 STCINT Seek/Tune Complete Interrupt. 0 = Tune complete has not been triggered. 1 = Tune complete has been triggered. Rev. 0.3 AN645 Table 12. Status Response for the AM Receiver Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT X ACFINT STCINT Bit Name 7 CTS Clear to Send. 0 = Wait before sending next command. 1 = Clear to send next command. 6 ERR Error 0 = No error. 1 = Error. 5:4 Reserved Values may vary. 3 RSQINT Received Signal Quality Interrupt 0 = Received Signal Quality measurement has not been triggered. 1 = Received Signal Quality measurement has been triggered. 2 Reserved Value may vary. 1 ACFINT Automatically Controlled Features Interrupt. 0 = ACF measurement has not been triggered. 1 = ACF measurement has been triggered. STCINT Seek/Tune Complete Interrupt. 0 = Tune complete has not been triggered. Do not send a new TUNE/SEEK command. 1 = Tune complete has been triggered. It is safe to send a new TUNE/ SEEK command. 0 Function Rev. 0.3 27 AN645 If the ERR bit in the STATUS response is set for a command or property, the response is redefined as follows: Table 13. Response When ERR Bit is Set Bit STATUS 7 6 CTS 1 5 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT ERROR RESP1 RESP 1 28 4 Bit Name 7:0 ERROR Rev. 0.3 Function Error definitions. 0x10=Bad command. 0x11=Bad ARG1. 0x12=Bad ARG2. 0x13=Bad ARG3. 0x14=Bad ARG4. 0x18=Command busy. 0x20=Bad internal memory. 0x30=Bad patch. 0x31=Bad boot mode. 0x40=Bad property. AN645 9.1.1. Common Receiver Commands Command 0x01 POWER_UP The POWER_UP command 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. This command powers up the device with the specified function (FM Receive, AM Receive). Power-up is complete when the CTS bit is set. This is the only command that may be sent while the device is powered down. Command Bit 7 6 5 4 IBIAS7X CTSIEN INTSEL 0 XIBIASHC 0 Bit 7 XIBIAS[2:0] FREQ[3:0] 00010 ARG5 1 FASTBOOT FUNC[3:0] ARG4 ARG 1 XSTART XCLOAD[5:0] 00 ARG2 ARG3 2 0x01 CMD ARG1 3 XMODE[2:0] Name Function IBIAS7X Crystal 7x bias current. 0=All other configurations. 1=Receiver 1 in a two/three receiver configuration with 37.209375, 36.4, or 37.8 MHz crystal. 1 6:0 XSTART Oscillator Startup. 0010001=Start up multiple tuner. 1110111=Normal operation. 2 7:6 Reserved Always write 00. Selects the amount of additional on-chip capacitance to be connected between XTAL1 and gnd and between XTAL2 and gnd. One half of the capacitance value shown here is the additional load capacitance presented to the xtal. The minimum step size is 0.277 pF. The required value will be layout-dependent. Range is 0–0x3F i.e.(0–16.33 pF) The Si477x EVB sets XCLOAD=0x28. 2 5:0 XCLOAD[5] 3 7 CTSIEN CTS interrupt enable. 0=Disable. 1=Enable. 3 6 INTSEL CTS interrupt pin select. 0=A1 pin. 1=INTB pin. 3 5 FASTBOOT 3 3 XIBIASHC Speeds boot time when set. It is recommended to set this bit with all crystals. Crystal high current. 0=Single receiver configuration. 1=Multiple receiver configuration. Rev. 0.3 29 AN645 ARG Bit Name 3 2:0 XIBIAS 4 7:4 FUNC[3:0 Function Crystal bias current. 0=37.209375, 36.4, or 37.8 MHz crystal or external clock. 7=37.209375, 36.4, or 37.8 MHz crystal. Selects the boot function of the device. 0 = Boot Loader. 1 = FM Receive. 2 = AM Receive. Note: Values other than those listed may result in unpredictable behavior. 30 4 3:0 FREQ[3:0] Selects the crystal frequency. 1 = 37.209375 MHz. 2 = 36.4 MHz. 3 = 37.8 MHz. 5 4 Reserved Always write 00010. 5 2:0 XMODE[2:0] Crystal mode. 1=Crystal. 2=External clock. Rev. 0.3 AN645 Command 0x02 PART_INFO The PART_INFO command returns the chip revision, part firmware major, minor, and build revision, and ROM ID. The command is complete when the CTS bit (and optional interrupt) is set. The command may only be sent in powerup mode. Command Bit 7 6 5 4 3 2 1 0 0x02 CMD Response Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT RESP1 CHIPREV[7:0] RESP1 PART[7:0] RESP3 PMAJOR[7:0] RESP4 PMINOR[7:0] RESP5 PBUILD[7:0] RESP6 Reserved RESP7 Reserved RESP8 ROMID[7:0] RESP Bit Name Function 1 7:0 CHIPPREV Chip Revision 2 7:0 PART Part Number, last two digits of part number 3 7:0 PMAJOR Part Major Revision 4 7:0 PMINOR Part Minor Revision 5 7:0 PBUILD Part Build Version 6 7:0 Reserved Values may vary. 7 7:0 Reserved Values may vary. 8 7:0 ROMID ROM ID Rev. 0.3 31 AN645 Command 0x11 POWER_DOWN The POWER_DOWN command moves the device from powerup to powerdown mode. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent when in powerup mode. Note that only the POWER_UP command is accepted in powerdown mode. If the system controller writes a command other than POWER_UP when in powerdown mode, the device will not respond. The device will only respond when a POWER_UP command is written. It is possible to power down a device and leave the oscillator running. This may be desirable in multiple receiver applications in which the device driving the oscillator for other devices is to be placed in powerdown without affecting the other devices. Command Bit 7 6 5 4 3 2 1 0 0x11 CMD 0 ARG1 ARG Bit Name 1 7:0 Reserved 2 0 XOSC XOSC Function Always write 0. 0=Full powerdown. 1=Powerdown and leave oscillator running. Response Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11). See Table 12 for status bits for AM Receive mode. 32 Rev. 0.3 AN645 Command 0x12 FUNC_INFO The FUNC_INFO command returns the firmware revision and patch revision for currently-loaded functional mode firmware (AM, FM). The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command Bit 7 6 5 4 3 2 1 0 0x12 CMD Response Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT RESP1 FWMAJOR[7:0] RESP2 FWMINOR1[7:0] RESP3 FWMINOR2[7:0] RESP4 PATCHH[7:0] RESP5 PATCHL[7:0] RESP6 FUNC[7:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7:0 FWMAJOR[7:0] Firmware Major Revision. 2 7:0 FWMINOR1[7:0] Firmware Minor1 Revision. 3 7:0 FWMINOR2[7:0] Firmware Minor2 Revision. 4 7:0 PATCHH[7:0] Patch ID High Byte (HEX). 5 7:0 PATCHL[7:0] Patch ID Low Byte (HEX). 6 7:0 FUNC[7:0] Returns the current functional mode: 1 FM Receive 2 AM Receive Rev. 0.3 33 AN645 Command 0x13 SET_PROPERTY The SET_PROPERTY command sets the value of a property. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Bit 7 6 5 4 3 CMD 0x13 ARG1 00000000 ARG2 PROPH[7:0] ARG3 PROPL[7:0] ARG4 PROPDH[7:0] ARG5 PROPDL[7:0] 2 1 0 ARG Bit Name Function 1 7:0 Reserved 2 7:0 PROPH [7:0] Property Address High Byte This byte, in combination with PROPL, is used to specify the property to modify. 3 7:0 PROPL [7:0] Property Address Low Byte This byte, in combination with PROPH, is used to specify the property to modify. 4 7:4 PROPDH [7:0] Property Value High Byte This byte, in combination with PROPDL, is used to set the property value. 5 7:0 PROPDL [7:0] Property Value Low Byte This byte, in combination with PROPDH, is used to set the property value. Always write to 0. Response Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. 34 Rev. 0.3 AN645 Command 0x14 GET_PROPERTY The GET_PROPERTY command retrieves a property's value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode Command Bit 7 6 5 4 3 CMD 0x14 ARG1 00000000 ARG2 PROPH[7:0] ARG3 PROPL[7:0] ARG Bit Name 1 7:0 Reserved 2 1 0 Function Always write 0. 2 7:0 PROPH[7:0] Property Address High Byte. This byte, in combination with PROPL, is used to specify the property to get. 3 7:0 PROPL[7:0] Property Address Low Byte. This byte, in combination with PROPH, is used to specify the property to get. Response Bit 7 6 5 STATUS CTS ERR 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT RESP1 XXXXXXXX RESP2 PROPDH[7:0] RESP3 PROPDL[7:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7:0 Reserved 2 7:0 PROPDH[7:0] Property Value High Byte. This byte, in combination with PROPDL, represents the requested property value. 3 7:0 PROPDL[7:0] Property Value Low Byte. This byte, in combination with PROPDH, represents Response values may vary. the requested property value. Rev. 0.3 35 AN645 Command 0x15 GET_INT_STATUS The GET_INT_STATUS command updates the bits of the status byte. This command should be called after any command that sets the STCINT, ACFINT, RDSINT, ASQINT, or RSQINT bits. When polling, this command should be periodically called to monitor the STATUS byte, and, when using interrupts, this command should be called after the interrupt is set to update the STATUS byte. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be set in powerup mode. Command Bit 7 6 5 4 3 2 1 0 0x15 CMD Response Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. Command 0x17 AGC_STATUS The AGC_STATUS command reports the current status of the AGC for FM mode. The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent when in powerup mode. Bit 7 6 5 4 2 1 0 3 2 1 0 RSQINT RDSINT ACFINT STCINT LNAHI LNALO X X 0x17 CMD RESP 7 6 STATUS CTS ERR RESP1 3 XX 5 4 XX MIXHI MXLO RESP2 FMAGC1 RESP3 FMAGC2 RESP4 PGAGAIN RESP5 FMLNAG Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. 36 Rev. 0.3 AN645 RESP Bit Name 1 7:6 Reserved 1 5 MXHI 0 = FM Mixer PD high threshold is not tripped. 1 = FM Mixer PD high threshold is tripped. 1 4 MXLO 0 = FM Mixer PD low threshold is not tripped. 1 = FM Mixer PD low threshold is tripped. 1 3 LNAHI 0 = FM LNA PD high threshold is not tripped. 1 = FM LNA PD high threshold is tripped. 1 2 LNALO 0 = FM LNA PD low threshold is not tripped. 1 = FM LNA PD low threshold is tripped. 1 1:0 Reserved Values may vary. FMAGC1 The parallel combination of these resistors indicates the current FMAGC1 attenuator resistance. The total resistance value at the pin is 800/FMAGC1. 0 = 10 k—no attenuation 1 = 800 2 = 400 4 = 200 8 = 100 16 = 50 32 = 25 64 = 12.5 128 = 6.25 2 7:0 Function Values may vary. 3 7:0 FMAGC2 The parallel combination of these resistors indicates the current FMAGC2 attenuator resistance. The total resistance value at the pin is 800/FMAGC2. 0 = 10 k—no attenuation 1 = 800 2 = 400 4 = 200 8 = 100 16 = 50 32 = 25 64 = 12.5 128 = 6.25 4 7:0 PGAGAIN PGA gain in dB Range: 8–33 5 7:0 FMLNAG FM LNA Gain in dB Range: 2–14 Rev. 0.3 37 AN645 Command 0x18 DIG_AUDIO_PIN_CFG The DIG_AUDIO_PIN_CFG command configures the digital audio pins. Ensure that DCLK and DFS are stable before this command is sent. Writing an argument byte to a non-zero value will change the state of a pin. Writing an argument byte to 0 will not change the state of the pin and is useful when using this command to query the state of the pins. The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command Bit 7 6 5 4 2 1 0 0x18 CMD ARG1 0 DCLK[6:0] ARG2 0 DFS[6:0] ARG3 0 DOUT[6:0] ARG4 0 BLEND[6:0] ARG Bit Name 1 7 Reserved Always write 0. Function 1 6:0 DCLK[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 10 = Configure this pin as part of the digital audio interface in slave mode. 2 7 Reserved Always write 0. 2 6:0 DFS[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 10 = Configure this pin as part of the digital audio interface in slave mode. 3 7 Reserved Always write 0. 3 6:0 DOUT[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 12 = Configure this pin as digital out on I2S port 1. 13 = Configure this pin as digital in on I2S port 1. (Si4777 only) 4 7 Reserved Always write 0. 4 38 3 6:0 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. BLEND[6:0] 13 = Configure this pin as digital in on I2S port 1. (Si4777 only) 23 = Configure this pin as the input that selects the mode of the I2S audio combiner (analog or HD) (Si4777 only). Rev. 0.3 AN645 Response Bit 7 6 5 4 STATUS CTS ERR RESP1 Reserved DCLK[6:0] RESP2 Reserved DFS[6:0] RESP3 Reserved DOUT[6:0] RESP4 Reserved BLEND[6:0] XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7 Reserved Values may vary. 1 6:0 DCLK[6:0] 1 = Disabled. 10 = Configured as part of the digital audio interface in slave mode. 2 7 Reserved Values may vary. 2 6:0 DFS[6:0] 1 = Disabled. 10 = Configured as part of the digital audio interface in slave mode. 3 7 Reserved Values may vary. 3 6:0 DOUT[6:0] 1 = Disabled. 12 = Configured as digital out on I2S port 1. 13 = Configured as digital in on I2S port 1. (Si4777 only) 4 7 Reserved Values may vary. 4 6:0 BLEND[6:0] 1 = Disabled. 13 = Configured as digital in on I2S port 1. 23 = Configured as the input that selects the mode of the I2S audio combiner (analog or HD). (Si4777 only) Rev. 0.3 39 AN645 Command 0x19 ZIF_PIN_CFG (Si4777 Only) The ZIF_PIN_CFG command configures the digital I/Q pins. Writing an argument byte to a non-zero value will change the state of a pin. Writing an argument byte to 0 will not change the state of the pin and is useful when using this command to query the state of the pins.The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command Bit 7 6 5 4 2 1 0 0x19 CMD ARG1 0 IQCLK[6:0] ARG2 0 IQFS[6:0] ARG3 0 IOUT[6:0] ARG4 0 QOUT[6:0] ARG Bit Name 1 7 Reserved Function Always write 0. 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 21 = Configure this pin as part of the I/Q interface in master mode. 1 6:0 IQCLK[6:0] 2 7 Reserved Always write 0. 2 6:0 IQFS[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 21 = Configure this pin as part of the I/Q interface in master mode. 3 7 Reserved Always write 0. 3 6:0 IOUT[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 22 = Configure this pin as I out. 4 7 Reserved Always write 0. QOUT[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 22 = Configure this pin as Q out. 4 40 3 6:0 Rev. 0.3 AN645 Response Bit 7 6 5 4 STATUS CTS ERR RESP1 Reserved IQCLK[6:0] RESP2 Reserved IQFS[6:0] RESP3 Reserved IOUT[6:0] RESP4 Reserved QOUT[6:0] XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7 Reserved 1 6:0 IQCLK[6:0] 2 7 Reserved Values may vary. 2 6:0 IQFS[6:0] 1 = Disabled. 21 = Configured as part of the I/Q interface in master mode. 3 7 Reserved Values may vary. 3 6:0 IOUT[6:0] 1 = Disabled. 22 = Configured I out. 4 7 Reserved Values may vary. 4 6:0 QOUT[6:0] 1 = Disabled. 22 = Configured Q out. Values may vary. 1 = Disabled. 21 = Configured as part of the I/Q interface in master mode. Rev. 0.3 41 AN645 Command 0x1A GPIO_CTL_PIN_CFG Configures the state (high or low) of GPO1 and GPO2 pins. The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command Bit 7 6 5 4 2 1 0 0x1A CMD ARG1 Reserved ICIN [6:0] ARG2 Reserved ICIP [6:0] ARG3 Reserved ICON[6:0] ARG4 Reserved ICOP[6:0] ARG Bit Name 1 7 Reserved Always write 0. Function 1 6:0 ICIN [6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down in enabled. 2 = Configure this pin as an output (GPO1) and drive it low. 3 = Configure this pin as an output (GPO1) and drive it high. 2 7 Reserved Always write 0. 2 6:0 ICIP [6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down in enabled. 2 = Configure this pin as an output (GPO2) and drive it low. 3 = Configure this pin as an output (GPO2) and drive it high. 3 7 Reserved Always write 0. 3 6:0 ICON[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down in enabled. 10 = Configure this pin as part of the digital audio interface in slave mode (DCLK). (Si4777 only). 4 7 Reserved Always write 0. ICOP[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down in enabled. 14 = Configure this pin as part of the digital audio interface in slave mode (DOUT). (Si4777 only). 4 42 3 6:0 Rev. 0.3 AN645 Response Bit 7 6 5 4 STATUS CTS ERR RESP1 Reserved ICIN[6:0] RESP2 Reserved ICIP[6:0] RESP3 Reserved ICON[6:0] RESP4 Reserved ICOP[6:0] XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7 Reserved Values may vary. 1 6:0 ICIN[6:0] 1 = Disabled. 2 = GPO1 output, Driving low. 3 = GPO1 output, Driving high. 2 7 Reserved Values may vary. 2 6:0 ICIP[6:0] 1 = Disabled. 2 = GPO2 output, Driving low. 3 = GPO2 output, Driving high. 3 7 Reserved Values may vary. 3 6:0 ICON[6:0] 1 = Disabled. 10 = Configured as part of the digital audio interface in slave mode on I2S port 2. (DCLK). (Si4777 only) 4 7 Reserved Values may vary. 4 6:0 ICOP[6:0] 1 = Disabled. 14 = Configured as digital out on I2S port 2 (DOUT). (Si47777 only). Rev. 0.3 43 AN645 Command 0x1B ANA_AUDIO_PIN_CFG The ANA_AUDIO_PIN_CFG command configures the analog audio pins. Writing an argument byte to 0 will not change the state of the pin and is useful when using this command to query the state of the pins. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Bit 7 6 5 4 2 1 0 0x1B CMD ARG1 0 ARG Bit Name 1 7 Reserved 1 3 LROUT[6:0] 6:0 Function Always write 0. LROUT[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable the output drivers, so the pins are completely inactive and can be left floating. 2 = Configure the LOUT/ROUT pins to output audio. 3 = Configure LOUT for MPX and disable ROUT. 4 = Configure LOUT/ROUT for HD Split mode: ROUT = Analog out; LOUT = HD out. Response Bit 7 6 STATUS CTS ERR RESP1 X 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT LROUT[6:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name 1 7 Reserved 1 44 6:0 LROUT[6:0] Function Values may vary. 1 = The output drivers are disabled, so the pins are completely inactive and can be left floating. 2 = LOUT/ROUT pins configured to output audio. 3 = LOUT is configured for MPX out and ROUT is disabled. Rev. 0.3 AN645 Command 0x1C INTB_PIN_CFG The INTB_PIN_CFG command configures INTB and A1 pins. Writing an argument byte to 0 will not change the state of the pin and is useful when using this command to query the state of the pins. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Bit 7 6 5 4 3 2 1 0 0x1C CMD ARG1 Reserved INTB[6:0] ARG2 Reserved A1[6:0] ARG Bit Name Function 1 7 Reserved Always write to 0. 1 6:0 INTB[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive and can be left floating. 10 = Configure this pin as part of the digital audio interface in slave mode. 40 = Configure this pin as the interrupt. 2 7 Reserved Always write to 0. 2 6:0 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive and can be left floating. 40 = Configure this pin as the interrupt. A1[6:0] Response Bit 7 6 5 4 Status CTS ERR RESP1 Reserved INTB[6:0] RESP 2 Reserved A1[6:0] XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. Rev. 0.3 45 AN645 46 RESP Bit Name Function 1 7 Reserved Values may vary. 1 6:0 INTB[6:0] 1 = Disabled. 10 = Configured as part of the digital audio interface in slave mode. 40 = Configured as the interrupt. 2 7 Reserved Values may vary. 2 6:0 A1[6:0] 1 = Disabled. 40 = Configured as the interrupt. Rev. 0.3 AN645 9.1.2. Common Receiver Properties Property 0x0000 INT_CTL_ENABLE The INT_CTL_ENABLE property enables top-level interrupt sources. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 INT_CTL_ENABLE 15:13 12 11 10 9 000 ASQREP RSQREP RDSREP ACFREP 000 0 0 0 0 8 7 6 STCREP CTSIEN ERRIEN 0 0 0 5 4 3 2 1 0 0 ASQIEN RSQIEN RDSIEN ACFIEN STCIEN 0 0 0 0 0 0 Bit Name Function 15:13 Reserved Always write 0. 12 ASQREP Repeat interrupt pulse when ASQINT is set, even if a previous interrupt was generated but not acknowledged. 11 RSQREP Repeat interrupt pulse when RSQINT is set, even if a previous interrupt was generated but not acknowledged. 10 RDSREP Repeat interrupt pulse when RDSINT is set, even if a previous interrupt was generated but not acknowledged. 9 ACFREP Repeat interrupt pulse when ACFINT is set, even if a previous interrupt was generated but not acknowledged. 8 STCREP Repeat interrupt pulse when STCIEN is set, even if a previous interrupt was generated but not acknowledged. 7 CTSIEN Interrupt when CTS is set. 6 ERRIEN Interrupt when ERR is set. 5 Reserved Always write 0. 4 ASQIEN Interrupt when ASQINT is set. 3 RSQIEN Interrupt when RSQIEN is set. 2 RDSIEN Interrupt when RDSINT is set. 1 ACFIEN Interrupt when ACFINT is set. 0 STCIEN Interrupt when STCIEN is set. Rev. 0.3 47 AN645 Property 0x0200 DIGITAL_IO_INPUT_SAMPLE_RATE (Si4777 only) The DIGITAL_IO_INPUT_SAMPLE_RATE property sets the digital input sample rate in units of Hz. Set the sample rate to 0 to disable digital audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 48000 Units: Hz DIGITAL_IO_INPUT_SAMPLE_RATE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 INPUT_SAMPLE_RATE[15:0] 0xBB80 48 Bit Name Function 15:0 INPUT_SAMPLE_RATE[15:0] Sets the digital input sample rate in units of Hz. Default is 48000. Range is 32000–48000. Rev. 0.3 AN645 Property 0x0201 DIGITAL_IO_INPUT_FORMAT (Si4777 only) The DIGITAL_IO_INPUT_FORMAT property configures digital audio input format. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be sent. This property may only be set or read in powerup mode. Default: 0x3600 DIGITAL_IO_INPUT_FORMAT 15 14 0x0 13 12 11 SLOT_SIZE[2:0] Bit Name 15:14 Reserved 13:11 10:8 10 SLOT_SIZE[2:0] SAMPL_SIZE[2:0] BITORDER 6 SWAP 4:1 0 CLKINV 8 7 6 5 SAMPL_SIZE[2:0] BITORDER SWAP 7 5 9 CLKINV 4 3 2 1 0 FRAMING_MODE[3:0] 0 Function Always write 0. Defines the width of the data channel. This is only used in right justified modes. 2 = 8 bits. 4 = 16 bits. 5 = 20 bits. 6 = 24 bits. Determines the number of bits in a sample. Only the specified number of bits per sample are used. The value of any bits sent over the sample size will be 0. Default is 24 bits. 2 = 8 bits. 4 = 16 bits. 5 = 20 bits. 6 = 24 bits. Determine if the MSB or LSB is transmitted first. Default is 0. 0 = Transmit MSB first. 1 = Transmit LSB first. SWAP—Swap position of the left and right channels. Default is 0. 0 = Transmit the left sample first. 1 = Transmit the right sample first. Inverts the data clock. Default is 0. 0 = The bit clock is not inverted. DFS will be captured on rising edge of DCLK. 1 = The bit clock is inverted. DFS will be captured on falling edge of DCLK. Determines when the data is transmitted relative to frame sync. 0x0 = I2S mode. 0x6 = DSP mode. FRAMING_MODE[3:0] 0x7 = Left-justified DSP mode. 0x8 = Left-justified mode. 0x9 = Right-justified mode. Reserved Always write 0. Rev. 0.3 49 AN645 Property 0x0202 DIGITAL_IO_OUTPUT_SAMPLE_RATE The DIGITAL_IO_OUTPUT_SAMPLE_RATE property sets the digital output sample rate in units of Hz. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 48000 Units: Hz DIGITAL_IO_OUTPUT_SAMPLE_RATE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 OUTPUT_SAMPLE_RATE[15:0] 0xBB80 50 Bit Name Function 15:0 OUTPUT_SAMPLE_RATE[15:0] Sets the digital output sample rate in units of Hz. Default is 48000. Range is 32000–48000. Rev. 0.3 AN645 Property 0x0203 DIGITAL_IO_OUTPUT_FORMAT The DIGITAL_IO_OUTPUT_FORMAT property configures digital audio output format. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x3600 DIGITAL_IO_OUTPUT_FORMAT 15 14 0x0 13 12 11 SLOT_SIZE[2:0] Bit Name 15:14 Reserved 13:11 10:8 10 SLOT_SIZE[2:0] SAMPL_SIZE[2:0] BITORDER 6 SWAP 4:1 0 CLKINV 8 7 6 5 SAMPL_SIZE[2:0] BITORDER SWAP 7 5 9 CLKINV 4 3 2 1 0 FRAMING_MODE[3:0] 0 Function Always write 0. Defines the width of the data channel. This is only used in right-justified modes. 2 = 8 bits. 4 = 16 bits. 5 = 20 bits. 6 = 24 bits. Determines the number of bits in a sample. Only the specified number of bits per sample are used. The value of any bits sent over the sample size will be 0. Default is 24 bits. 2 = 8 bits. 4 = 16 bits. 5 = 20 bits. 6 = 24 bits. Determine if the MSB or LSB is transmitted first. Default is 0. 0 = Transmit MSB first. 1 = Transmit LSB first. SWAP—Swap position of the left and right channels. Default is 0. 0 = Transmit the left sample first. 1 = Transmit the right sample first. Inverts the data clock. Default is 0. 0 = The bit clock is not inverted. DFS will be captured on rising edge of DCLK. 1 = The bit clock is inverted. DFS will be captured on falling edge of DCLK. Determines when the data is transmitted relative to frame sync. 0x0 = I2S mode. 0x6 = DSP mode. FRAMING_MODE[3:0] 0x7 = Left-justified DSP mode. 0x8 = Left-justified mode. 0x9 = Right-justified mode. Reserved Always write 0. Rev. 0.3 51 AN645 Property 0x0300 AUDIO_ANALOG_VOLUME The AUDIO_ANALOG_VOLUME property sets the analog audio volume. A value of 0 will mute the audio; a value of 1 applies 62 dB of attenuation, and a value of 63 applies no attenuation. Each step accounts for 1 dB of change in the output. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 63 AUDIO_ANALOG_VOLUME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 0x000 VOL[5:0] 0x000 0x3F Bit Name 15:6 Reserved Always write 0. 5:0 VOL[5:0] Sets the analog audio volume. Default is 63. Range is 0–63. 1 0 Function Property 0x0301 AUDIO_MUTE The AUDIO_MUTE property mutes/unmutes each audio output (analog left or analog right).The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 0x0000 AUDIO_MUTE 15 52 14 13 12 11 10 Bit Name 15:2 Reserved 1 RIGHTMUTE 0 LEFTMUTE 9 8 7 6 5 4 3 2 1 0 0x0000 RIGHTMUTE LEFTMUTE 0x0000 0 0 Function Always write 0. 0 = Right audio is not muted. 1 = Right audio is muted. 0 = Left audio is not muted. 1 = Left audio is muted. Rev. 0.3 AN645 Property 0x0600 ZIF_OUTPUT_CFG (Si4777 Only) The ZIF_OUTPUT_CFG property enables/disables ZIF and configures the ZIF interface format. The ZIF data rate depends on RCLK and the radio's operational mode. Changes to this property will take effect at tune time. The ZIF pins must also be configured, see ZIF_PIN_CFG on page 40. Refer to the Si477x data sheet for details on interface format and data rates. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be sent in power-up mode. Default: 0x0801 ZIF_OUTPUT_CFG 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FILL[1:0] RESERVED[7:0] FALL ZIF_FORMAT[3:0] RESERVED 0x0 0x20 0 0x0 1 Bit Name 15:14 FILL[1:0] 13:6 RESERVED[7:0] 5 FALL 4:1 ZIF_FORMAT[3:0] 0 RESERVED Function FILL[1:0]—Defines the fill value for unused data bits. Default 0. 0 = The unused bits are filled with 0s. 1 = The unused bits are filled with 1s. 2 = The unused bits are sign extended. 3 = The unused bits are filled with a random sequence. Always write as 0x20 FALL—IQCLK invert. Default 0. 0 = Output data changes concurrently with the falling edge of IQCLK. 1 = Output data changes concurrently with the rising edge of IQCLK. Default: 0x0 0x0 = I2S ZIF format (Default). 0x8 = Left-justified ZIF format. 0x9 = Right-justified ZIF format. 0xE = DSP ZIF format . 0xF = DSP Left-justified ZIF format. Always write 1. Rev. 0.3 53 AN645 9.2. Commands and Properties for FM Receiver Table 14. FM Receiver Command Summary Number Name Summary 0x30 FM_TUNE_FREQ Tunes the FM receiver to a frequency in 10 kHz steps. 0x31 FM_SEEK_START Initiates a seek for a channel that meets the validation criteria for FM. 0x32 FM_RSQ_STATUS Returns status information about the received signal quality. 0x35 FM_ACF_STATUS Returns status information about automatically-controlled features for the tuned station. 0x36 FM_RDS_STATUS Returns RDS information for current channel and reads an entry from the RDS FIFO. 0x37 FM_RDS_BLOCKCOUNT Returns RDS expected, received, and uncorrectable block statistic information. Table 15. FM Receiver Property Summary Number Name 0x0302 AUDIO_DE_EMPHASIS Default Summary 0x0000 Sets the FM Receive de-emphasis. 0 0x0008 0x0400 FM_SOFT_MUTE_MAX_ATTENUATION Sets the maximum soft mute attenuation. 8 0x0401 0x0008 FM_SOFT_MUTE_TRIGGER_ THRESHOLD Sets the SNR threshold for soft mute to start. 8 0x0000 0x0402 FM_SOFT_MUTE_END_THRESHOLD 0 0x01F4 0x0403 FM_SOFT_MUTE_RELEASE_TIME 500 Sets the SNR threshold where soft mute will stop attenuating. Sets the maximum soft mute release time in ms. 0x0078 0x0404 FM_SOFT_MUTE_ATTACK_TIME Sets the maximum soft mute attack time in ms. 120 0x0000 0x0700 FM_AGC_FE_CONFIG 0 54 Rev. 0.3 Specified the input path for RF signal and other FE configuration options. AN645 Table 15. FM Receiver Property Summary (Continued) Number Name 0x0701 FM_AGC_PD_CONFIG Default 0x0270 624 Summary Specifies the behavior of the FM peak detectors and attenuators. FM_LNA_AGC_ATTACK_MS 0x0004 Sets the number of milliseconds the wideband RF high-peak detector must be exceeded before 4 attenuating the appropriate block. 0x0703 FM_LNA_AGC_RELEASE_MS 0x0050 Sets the number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate 80 block. 0x0704 FM_LNA_AGC_PD_THRESHOLD 0x0702 0x4F05 20229 Sets the high threshold and hysteresis for the LNA peak detector. FM_MIXER_AGC_ATTACK_MS 0x0004 Sets the number of milliseconds the wideband mixer high-peak detector must be exceeded before attenuating the appropriate block. 4 0x0706 FM_MIXER_AGC_RELEASE_MS 0x0050 Sets the number of milliseconds the wideband mixer low-peak detector must not be exceeded before increasing the gain of the appropriate 80 block. 0x0707 FM_MIXER_AGC_PD_THRESHOLD 0x0705 0x5503 21763 0x0000 0x0710 FM_AGC_OVERRIDE 0 Sets the high threshold and hysteresis for the mixer peak detector. Overrides the AGC setting by disabling the AGC and forcing the gain to be maximum. 0x1100 FM_SEEK_BAND_BOTTOM 0x222E Sets the lower seek boundary of the FM band 8750 in multiples of 10 kHz. 0x1101 FM_SEEK_BAND_TOP 0x2A26 Sets the upper seek boundary for the FM band 10790 in multiples of 10 kHz. 0x1102 FM_SEEK_FREQUENCY_SPACING 0x000A Sets the frequency spacing for the FM band in multiples of 10 kHz when performing a seek. 10 0x1200 FM_RSQ_INTERRUPT_SOURCE 0x0000 Configures interrupt related to Received Signal Quality metrics (FM_RSQ_STATUS). 0 0x1201 FM_RSQ_SNR_HIGH_THRESHOLD 0x007F Sets high threshold which triggers the RSQ interrupt if the SNR is above this threshold. 127 0x1202 FM_RSQ_SNR_LOW_THRESHOLD 0xFF80 Sets low threshold which triggers the RSQ –128 interrupt if the SNR is below this threshold. Rev. 0.3 55 AN645 Table 15. FM Receiver Property Summary (Continued) Number Name 0x1203 FM_RSQ_RSSI_HIGH_THRESHOLD 0x007F Sets high threshold which triggers the RSQ interrupt if the RSSI is above this threshold. 127 0x1204 FM_RSQ_RSSI_LOW_THRESHOLD 0xFF80 Sets low threshold which triggers the RSQ –128 interrupt if the RSSI is below this threshold. 0x1207 FM_RSQ_MULTIPATH_HIGH_ THRESHOLD 0x007F Sets high threshold which triggers the RSQ interrupt if Multipath is above this threshold. 127 0x1208 FM_RSQ_MULTIPATH_LOW_ THRESHOLD 0x0000 Sets low threshold which triggers the RSQ interrupt if Multipath is below this threshold. 0 0x1300 FM_ACF_INTERRUPT_SOURCE 0x1301 FM_ACF_SM_THRESHOLD 0x1302 FM_ACF_CHBW_THRESHOLD 0x0000 Sets the Channel Filter Bandwidth interrupt threshold in units of kHz. 0 0x1303 FM_ACF_HICUT_THRESHOLD 0x0000 Sets the Hi-cut interrupt threshold in units of 100 Hz. 0 0x1304 FM_ACF_HIBLEND_THRESHOLD 0x1305 FM_ACF_BLEND_THRESHOLD 0x1306 FM_ACF_CONTROL_SOURCE 0x2000 FM_VALID_MAX_TUNE_ERROR 0x2001 FM_VALID_RSSI_TIME 0x0006 Sets the amount of time in milliseconds to allow the RSSI metric to settle before evaluat6 ing. 0x2002 FM_VALID_SNR_TIME 0x0012 Sets the amount of time in milliseconds to allow the SNR metric to settle before evaluat18 ing. 0x2003 FM_VALID_SNR_THRESHOLD 0x0008 Sets the SNR threshold for a valid FM Seek/ Tune. 8 0x2004 FM_VALID_RSSI_THRESHOLD 0x000C Sets the RSSI threshold for a valid FM Seek/ Tune. 12 0x200A FM_VALID_ASSI_THRESHOLD 0x503C Sets the ASSI/ASSI200 threshold for a valid 20540 FM Seek/Tune. 56 Default 0x0000 0 0x001F 31 Summary Enables the ACF interrupt sources. Sets the softmute interrupt threshold in dB. 0x0000 Sets the Hi-blend interrupt threshold in units of 100 Hz. 0 0x0000 Sets the Stereo Blend interrupt threshold in units of % L-R gain. 0 0x0001 1 Sets the controlling metric for ACF features. 0x004B Sets the maximum frequency error in 2 ppm allowed before setting the AFCRL indicator. 75 Rev. 0.3 AN645 Table 15. FM Receiver Property Summary (Continued) Number Name Default Summary 0x2200 FM_CHBW_RSSI_MIN_MAX 0x2201 FM_CHBW_SQ_HIGH_THRESHOLD 0x000C Sets the RSSI/DEV threshold for maximum channel filter bandwidth. 12 0x2202 FM_CHBW_SQ_LOW_THRESHOLD 0xFFFC Sets the RSSI/DEV threshold for minimum channel filter bandwidth. –4 0x2203 FM_CHBW_SQ_WIDENING_TIME 0x2204 FM_CHBW_SQ_NARROWING_TIME 0x2205 FM_CHBW_ASSI_MIN_MAX 0x9623 Sets the 100 kHz blocker delta (difference between HASSI and LASSI) for maximum and 38435 minimum channel BW in units of kHz. 0x2206 FM_CHBW_ASSI_LOW_THRESHOLD 0x0007 Sets the 100kHz blocker delta (difference between HASSI and LASSI) threshold for max7 imum channel filter bandwidth. 0x2207 FM_CHBW_ASSI_HIGH_THRESHOLD 0x0014 Sets the 100kHz blocker delta (difference between HASSI and LASSI) threshold for mini20 mum channel filter bandwidth. 0x2208 FM_CHBW_ASSI_WIDENING_TIME 0x0C80 Sets the channel filter bandwidth widening time based on the 100 kHz blocker delta (difference 3200 between HASSI and LASSI). 0x2209 FM_CHBW_ASSI_NARROWING_TIME 0x0140 Sets the channel filter bandwidth narrowing time based on the 100 kHz blocker delta (dif320 ference between HASSI and LASSI). 0x220A FM_CHBW_ASSI200_MIN_MAX 0x9650 Sets the 200 kHz blocker strength maximum 38480 and minimum channel BW in units of kHz. 0x220B FM_CHBW_ASSI200_LOW_THRESHOLD 0xFFF6 Sets the 200 kHz blocker strength threshold for maximum channel filter bandwidth. –10 0x220C FM_CHBW_ASSI200_HIGH_THRESHOLD 0x000A Sets the 200 kHz blocker strength threshold for minimum channel filter bandwidth. 10 0x220D FM_CHBW_ASSI200_WIDENING_TIME 0x0C80 Sets the channel filter bandwidth widening time 3200 based on 200 kHz blocker strength. 0x220E FM_CHBW_ASSI200_NARROWING_ TIME 0x220F FM_CHBW_WEAKSIG_THR 0x9637 Sets the maximum and minimum channel BW 38455 in units of kHz based on RSSI/DEV. 0x0010 Sets the channel filter bandwidth widening time based on RSSI/DEV. 16 0x0800 Sets the channel filter bandwidth narrowing 2048 time based on RSSI/DEV. 0x140 320 Sets the channel filter bandwidth narrowing time based on 200 kHz blocker strength. 0x100D Sets the hysteresis window for the weak signal 4109 channel filter bandwidth engine. Rev. 0.3 57 AN645 Table 15. FM Receiver Property Summary (Continued) Number Name 0x2210 FM_CHBW_BLOCKER_THR 0x3105 FM_LOWCUT_MIN_FREQ 0x3106 FM_LOWCUT_MAX_FREQ 0x3300 FM_IBOC_CONTROL 0x3301 FM_IBOC_ANALOG_TO_HD_ CROSSFADE_TIME 0x03E8 Sets the crossfade time between full analog 1000 and full HD Digital audio in ms. (Si4777 only). 0x3302 FM_IBOC_HD_TO_ANALOG_ CROSSFADE_TIME 0x03E8 Sets the crossfade time from full HD Digital 1000 audio to full analog audio in ms. (Si4777 only). 0x3303 FM_IBOC_DYNAMIC_GAIN 0x007F Sets the digital audio dynamic linear scaling factor. (Si4777 only). 127 0x3304 FM_IBOC_STATIC_GAIN 0x0100 Sets the digital audio static linear gain factor. (Si4777 only). 256 0x3400 FM_MULT_EQ_CTL 0x3401 FM_MULT_EQ_NOISE_DISABLE 0xFC81 Sets the RSSI threshold below which the channel equalizer will use noise measurements to 64641 enable/disable the channel equalizer. 0x3500 FM_BLEND_RSSI_THRESHOLDS 0x3719 Sets the thresholds for the RSSI metric for the 14105 stereo blend mitigation engine. 0x3501 FM_BLEND_RSSI_STEREO_SEP 0x2D00 Set the limits for the stereo separation when driven by RSSI on the stereo blend mitigation 11520 engine. 0x3502 FM_BLEND_RSSI_ATTACK_TIME 0x3503 FM_BLEND_RSSI_RELEASE_TIME 0x3508 FM_BLEND_MULTIPATH_ THRESHOLDS 0x1E3C Sets the thresholds for the multipath metric for 7740 the stereo blend mitigation engine. 0x3509 FM_BLEND_MULTIPATH_ STEREO_SEP 0x2D00 Sets the limits for the stereo separation when driven by multipath on the stereo blend mitiga11520 tion engine. 58 Default 0x140A 5130 0x0000 0 0x0000 0 0x0000 0 0x1401 5121 0x0010 16 0x0FA0 4000 Rev. 0.3 Summary 200 kHz stereo blocker threshold control Sets the minimum LowCut cutoff frequency Sets the maximum LowCut cutoff frequency Control property for IBOC Blend (Si4777 only). Controls the multipath channel equalizer. Sets the stereo blend attack time in ms. Sets the stereo blend release time in ms. AN645 Table 15. FM Receiver Property Summary (Continued) Number Name Default 0x350A FM_BLEND_MULTIPATH_ATTACK_TIME 0x350B FM_BLEND_MULTIPATH_ RELEASE_TIME 0x3510 FM_BLEND_USN_THRESHOLDS 0x341B Set the thresholds for the USN metric for the 13339 stereo blend mitigation engine. 0x3511 FM_BLEND_USN_STEREO_SEP 0x2D00 Sets the limits for the stereo separation when driven by USN on the stereo blend mitigation 11520 engine. 0x3512 FM_BLEND_USN_ATTACK_TIME 0x3513 FM_BLEND_USN_RELEASE_TIME 0x3600 FM_HICUT_RSSI_THRESHOLDS 0x230F Sets the thresholds for the RSSI metric for the 8975 high cut mitigation engine. 0x3601 FM_HICUT_RSSI_CUTOFF_FREQ 0xB428 Sets the limits for the cutoff frequency when driven by RSSI on the high cut mitigation 46120 engine. 0x3602 FM_HICUT_RSSI_ATTACK_TIME 0x3603 FM_HICUT_RSSI_RELEASE_TIME 0x3608 FM_HICUT_ MULTIPATH_THRESHOLDS 0x3250 Sets the thresholds for the multipath metric for 12880 the high cut mitigation engine. 0x3609 FM_HICUT_ MULTIPATH_CUTOFF_FREQ 0xB428 Set the limits for the cutoff frequency when driven by multipath on the high cut mitigation 46120 engine. 0x360A FM_HICUT_ MULTIPATH_ATTACK_TIME 0x360B FM_HICUT_ MULTIPATH_RELEASE_TIME 0x3610 FM_HICUT_ USN_THRESHOLDS 0x0010 16 0x0FA0 4000 0x0010 16 0x0FA0 4000 0x0010 16 0x0FA0 4000 0x0010 16 0xFA0 4000 Summary Sets the stereo blend attack time in ms. Sets the stereo blend release time in ms. Sets the stereo blend attack time in ms. Sets the stereo blend release time in ms. Sets the high cut attack time in ms. Sets the high cut release time in ms. Sets the high cut attack time in ms. Sets the high cut release time in ms. 0x250F Sets the thresholds for the USN metric for the 9487 high cut mitigation engine. Rev. 0.3 59 AN645 Table 15. FM Receiver Property Summary (Continued) Number Name 0x3611 FM_HICUT_ USN_CUTOFF_FREQ 0x3612 FM_HICUT_USN_ATTACK_TIME 0x3613 FM_HICUT_USN_RELEASE_TIME 0x3700 FM_HIBLEND_RSSI_THRESHOLDS 0x371B Sets the thresholds for the RSSI metric for the 14107 high blend mitigation engine. 0x3701 FM_HIBLEND_RSSI_CUTOFF_FREQ 0xB41E Sets the limits for the cutoff frequency when driven by RSSI on the high blend mitigation 46110 engine. 0x3702 FM_HIBLEND_RSSI_ATTACK_TIME 0x3703 FM_HIBLEND_RSSI_RELEASE_TIME 0x3708 FM_HIBLEND_MULTIPATH_ THRESHOLDS 0x193C Sets the thresholds for the multipath metric for 6460 the high blend mitigation engine. 0x3709 FM_HIBLEND_MULTIPATH_ CUTOFF_FREQ 0xB41E Sets the limits for the cutoff frequency when driven by multipath on the Hi-blend mitigation 46110 engine. 0x370A FM_HIBLEND_MULTIPATH_ ATTACK_TIME 0x0004 0x370B FM_HIBLEND_MULTIPATH_ RELEASE_TIME 0x1F40 0x3710 FM_HIBLEND_USN_ THRESHOLDS 0x3711 FM_HIBLEND_USN_CUTOFF_FREQ 0x3712 FM_HIBLEND_USN_ATTACK_TIME 0x3713 FM_HIBLEND_USN_RELEASE_TIME 0x4000 FM_RDS_INTERRUPT_SOURCE 60 Default Summary 0xB428 Sets the limits for the cutoff frequency when driven by USN on the high cut mitigation 46120 engine. 0x0010 16 0x0FA0 4000 0x0004 4 0x1F40 8000 4 8000 Sets the high cut attack time in ms. Sets the high cut release time in ms. Sets the high blend attack time in ms. Sets the high blend cut release time in ms. Sets the high blend attack time in ms. Sets the high blend release time in ms. 0x371E Sets the thresholds for the USN metric for the 14110 high blend mitigation engine. 0xB41E Sets the limits for the cutoff frequency when driven by USN on the high blend mitigation 46110 engine. 0x0004 4 0x1F40 8000 0x0000 0 Rev. 0.3 Sets the high blend attack time in ms. Sets the high blend release time in ms. Configures interrupt related to RDS. AN645 Table 15. FM Receiver Property Summary (Continued) Number Name Default Summary 0x4001 FM_RDS_INTERRUPT_FIFO_COUNT 0x0000 Sets the minimum number of RDS groups stored in the RDS FIFO before RDSRECV is 0 set. 0x4002 FM_RDS_CONFIG 0x0000 Configures RDS settings to enable RDS processing (RDSEN) and set RDS block error 0 thresholds. 0x4003 FM_RDS_CONFIDENCE 0x1111 Sets the confidence level requirement for each 4369 RDS block. Rev. 0.3 61 AN645 9.2.1. FM Receiver Commands Command 0x30 FM_TUNE_FREQ The FM_TUNE_FREQ command sets the FM Receiver to tune to a frequency between 64 and 108 MHz in 10 kHz units. The CTS bit (and optional interrupt) is set when it is safe to send the next command. The ERR bit (and optional interrupt) is set if an invalid argument is sent. Note that only a single interrupt occurs if both the CTS and ERR bits are set. The optional STC interrupt is set when the command completes. This command may only be sent in powerup mode. The command clears the STC bit if it is already set. Command Bit 7 6 5 4 3 0 HD TUNEMODE[1:0] 0 ARG2 FREQH[7:0] ARG3 FREQL[7:0] ARG Bit Name 1 7 Reserved 1 6 HD 0 SMOOTHMETRICS 0 Function Always write 0. Places the part in the HD mode. 0 = Normal Bandwidth. 1 = Wide-Bandwidth/HD Mode. Sets the desired tuning mode. 0 = Validated normal tune: Unconditionally stay on the new channel after tune, tune status is valid. 1 = Invalidated fast tune: Unconditionally stay on the new channel after tune, tune status invalid. 1 5:4 TUNEMODE[1:0] 1 3 Reserved Always write 0. 1 2 SMOOTHMETRICS Smoothly transition audio state after tune. 0 = Initialize audio state to match this new channel. 1 = Transition audio state from previous channel values to the new channel values. 1 1:0 Reserved Always write 0. 2 3 62 1 0x30 CMD ARG1 2 7:0 7:0 FREQH[7:0] Tune Frequency High Byte. This byte in combination with FREQL selects the tune frequency in units of 10 kHz. In FM mode the valid range is from 6400 to 10800 (64–108 MHz). FREQL[7:0] Tune Frequency Low Byte. This byte in combination with FREQH selects the tune frequency in units of 10 kHz. In FM mode, the valid range is from 6400 to 10800 (64–108 MHz). Rev. 0.3 AN645 Response Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT Command 0x31 FM_SEEK_START The FM_SEEK_START command begins searching for a valid station. In order for a station to be considered valid, each of the following thresholds must be met: FM_VALID_SNR_THRESHOLD and FM_VALID_RSSI_THRESHOLD and FM_VALID_MAX_TUNE_ERROR. Clears any pending STCINT, RSQINT, or RDSINT interrupt status. Seek can be cancelled through setting the CANCEL bit in the FM_RSQ_STATUS command. The CTS bit (and optional interrupt) is set when it is safe to send the next command. The ERR bit (and optional interrupt) is set if an invalid argument is sent. Note that only a single interrupt occurs if both the CTS and ERR bits are set. The optional STC interrupt is set when the command completes. This command may only be sent in powerup mode. The command clears the STCINT bit if it is already set. Command Bit 7 6 5 4 3 2 SEEKUP WRAP 1 0 0x31 CMD 0000 ARG1 00 ARG Bit Name Function 1 7:4 Reserved Always write 0. 1 3 SEEKUP Seek Up/Down. Determines the direction of the search, either UP = 1, or DOWN = 0. 1 2 WRAP 1 1:0 Reserved Wrap/Halt. Determines whether the seek should Wrap = 1, or Halt = 0 when it hits the band limit. Always write 0. Response Bit 7 6 STATUS CTS ERR 5 4 XX Rev. 0.3 3 2 1 0 RSQINT RDSINT ACFINT STCINT 63 AN645 Command 0x32 FM_RSQ_STATUS The FM_RSQ_STATUS command returns status information about the received signal quality. This command returns the Received Signal Strength Indicator (RSSI), Signal to Noise Ratio (SNR), Adjacent Channel Strength for 200 kHz (ASSI), Adjacent Channel Strength for 100 kHz (LASSI and HASSI), frequency offset (FREQOFF), Multipath (MULT) and Ultrasonic Noise (USN) associated with the desired channel. It also indicates valid channel (VALID) and AFC rail status (AFCRL). This command can be used to check if the received signal is above the RSSI high threshold as reported by RSSIHINT or below the RSSI low threshold as reported by RSSILINT. It can also be used to check if the signal is above the SNR high threshold as reported by SNRHINT or below the SNR low threshold as reported by SNRLINT. It can be used to check if the detected multipath is above the Multipath high threshold as reported by MULTHINT or below the Multipath low threshold as reported by MULTLINT. The command clears the RSQINT, BLENDINT, SNRHINT, SNRLINT, RSSIHINT, RSSILINT, MULTHINT, and MULTLINT interrupt bits when the RSQACK bit of ARG1 is set. If the condition is still true after the interrupt is cleared, another interrupt will fire assuming that bit is enabled in FM_RSQ_INTERRUPT_SOURCE. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent when in powerup mode. FM_RSQ_ STATUS Command 7 6 5 4 CMD 2 1 0 RSQACK ATTUNE CANCEL STCACK 0x32 ARG1 64 3 000 0 ARG Bit Name Function 1 7:5 Reserved Always write 0. 1 4 Reserved Always write 0. 1 3 RSQACK Clears RSQINT, SNRHINT, SNRLINT, RSSIHINT, RSSILINT, BLENDINT, MULTHINT, and MULTLINT if set. 1 2 ATTUNE Returns the values of metrics as of tune time. When the AT_TUNE bit is set, values returned for RSQ_STATUS are the values calculated at tune and do not change unless another FM_TUNE_FREQ command is called. This feature can be used to determine why seek stopped at the current station. 1 1 CANCEL Aborts a seek or tune currently in progress. 0 = Don't abort. 1 = Abort. 1 0 STCACK Clears the STC interrupt status indicator if set. Rev. 0.3 AN645 Response Bit 7 6 STATUS CTS ERR RESP1 RESP 2 MULTHINT MULTLINT BLTF X 5 4 XX X X 3 2 1 0 RSQINT RDSINT ACFINT STCINT SNRHINT SNRLINT RSSIHINT RSSILINT SNRREADY RSSIREADY X RESP 3 READFREQ[15:8] RESP 4 READFREQ[7:0] RESP 5 FREQOFF[7:0] RESP 6 RSSI[7:0] RESP 7 SNR[7:0] RESP 8 XXXXXXXX RESP 9 LASSI[7:0] RESP 10 HASSI[7:0] RESP 11 MULT[7:0] RESP 12 DEV[7:0] RESP 13 XX RESP 14 XX RESP 15 ASSI200[7:0] RESP 16 USN[7:0] RESP 17 PILOTDEV[7:0] RESP 18 RDSDEV[7:0] RESP 19 ASSI200DEV[7:0] RESP 20 STRONGDEV[7:0] RESP 21 RDSPI[15:8] RESP 22 RDSPI[7:0] Rev. 0.3 X AFCRL VALID 65 AN645 RESP Bit Name 1 7 MULTHINT Function Multipath Detect High. 0 = Indicates that multipath value has not exceeded the Multipath high threshold set by FM_RSQ_MULTIPATH_HIGH_THRESHOLD. 1 = Indicates that multipath value has exceeded the Multipath high threshold set by FM_RSQ_MULTIPATH_HIGH_THRESHOLD. 1 6 MULTLINT Multipath Detect Low. 0 = Indicates that multipath value has not fallen below the Multipath low threshold set by FM_RSQ_MULTIPATH_LOW_THRESHOLD. 1 = Indicates that multipath value has fallen below the Multipath low threshold set by FM_RSQ_MULTIPATH_LOW_THRESHOLD. 1 5:4 Reserved Values may vary. 1 3 SNRHINT SNR Detect High. 0 = Indicates that the received signal SNR has not exceeded the SNR high threshold set by FM_RSQ_SNR_HIGH_THRESHOLD 1 = Indicates that the received signal SNR has exceeded the SNR high threshold set by FM_RSQ_SNR_HIGH_THRESHOLD. 1 2 SNRLINT SNR Detect Low. 0 = Indicates that the received signal SNR has not fallen below the SNR low threshold set by FM_RSQ_SNR_LOW_THRESHOLD. 1 = Indicates that the received signal SNR has fallen below the SNR low threshold set by FM_RSQ_SNR_LOW_THRESHOLD. 1 1 RSSIHINT RSSI Detect High. 0 = Indicates that the received signal RSSI has not exceeded the RSSI high threshold set by FM_RSQ_RSSI_HIGH_THRESHOLD. 1 = Indicates that the received signal RSSI has exceeded the RSSI high threshold set by FM_RSQ_RSSI_HIGH_THRESHOLD. 1 0 RSSILINT RSSI Detect Low. 0 = Indicates that the received signal RSSI has not fallen below the RSSI low threshold set by FM_RSQ_RSSI_LOW_THRESHOLD. 1 = Indicates that the received signal RSSI has fallen below the RSSI low threshold set by FM_RSQ_RSSI_LOW_THRESHOLD. 66 Rev. 0.3 AN645 RESP Bit Name Function 2 7 BLTF 2 6 Reserved 2 5 SNR READY The SNRREADY and RSSIREADY bits indicate that the RSSI/SNR have been read as a result of a tune command. If either one of these bits are 0 this indicates that either the metric is being measured (because a tune is in progress) or that the metric was not measured during tune because the station was invalidated before the metric could be measured. In the case where a metric was not measured during tune, the tune time RSQ status will read back as 0 for the unmeasured metric. The normal running time status for these metrics is not affected and will report normally. 0 = SNR measurement in progress (tune in progress) or not taken (tune completed). 1 = SNR measurement ready. 2 4 RSSIREADY The SNRREADY and RSSIREADY bits indicate that the RSSI/SNR have been read as a result of a tune command. If either one of these bits are 0 this indicates that either the metric is being measured (because a tune is in progress) or that the metric was not measured during tune because the station was invalidated before the metric could be measured. In the case where a metric was not measured during tune, the tune time RSQ status will read back as 0 for the unmeasured metric. The normal running time status for these metrics is not affected and will report normally. 0 = RSSI measurement in progress (tune in progress) or not taken (tune completed). 1 = RSSI measurement ready. 2 3:2 Reserved 2 1 AFCRL Set if the AFC rails. AFC gets railed if FREQOFF > MAX_TUNE_ERROR. 2 0 VALID Reports if the channel is valid based on the settings of FM_VALID_RSSI_THRESHOLD, FM_VALID_SNR_THRESHOLD, FM_VALID_MAX_TUNE_ERROR 3,4 15:0 READFREQ[15:0] 5 7:0 FREQOFF[7:0] 6 7:0 RSSI[7:0] Received Signal Strength indicator in dBµV (–128 to 127) 7 7:0 SNR[7:0] RF SNR indicator in dB (–128 to 127). 8 7:0 Reserved Values may vary. Band Limit. Reports if a seek hits the band limit (WRAP = 0 in FM_START_SEEK) or wrapped to the original frequency (WRAP = 1). Values may vary. Values may vary. Returns the currently tuned frequency. Signed frequency offset in units of 2 ppm (–128 to 127) Rev. 0.3 67 AN645 RESP Bit Name Function 9 7:0 LASSI[7:0] Low side Adjacent (100 kHz) Channel Strength Indicator reports the (Signal + Noise) power relative to the carrier.(–128 to 127) 10 7:0 HASSI[7:0] High side Adjacent (100 kHz) Channel Strength Indicator reports the (Signal + Noise) power relative to the carrier.(–128 to 127) 11 7:0 MULT[7:0] Multipath indicator (0–127%). 12 7:0 DEV[7:0] Frequency Deviation metric in kHz. 13, 14 15:0 Reserved Values may vary. 15 7:0 ASSI200[7:0] 16 7:0 USN[7:0] 17 7:0 PILOTDEV[7:0] Pilot deviation in units of 100 Hz. 18 7:0 RDSDEV[7:0] RDS deviation in units of 100 Hz. 19 7:0 ASSI200DEV[7:0] Adjacent Channel (±200 kHz) Deviation in units of 1.45 kHz. 20 7:0 STRONGDEV[7:0] Deviation of strong desired signals. This is an alternative to DEV, which can become erroneous in the presence of very strong signals. Approximately, deviation in kHz = STRONGDEV x f(mod), where f(mod) is 5.55 kHz for mono signals or 2.75 kHz for stereo signals 21, 22 68 15:0 RDSPI[15:0] Adjacent Channel (±200 kHz) Strength Indicator reports the (Signal + Noise) power relative to the carrier. This metric reports the sum of high and low adjacent channel strengths. (–128 to 127) Ultrasonic Noise Indicator in –dBFS (0 to 127). 127 corresponds to 127 dB down from full scale. RDS PI code. Rev. 0.3 AN645 Command 0x35 FM_ACF_STATUS The FM_ACF_STATUS command returns status information about automatically-controlled features. This command returns the Soft Mute Attenuation, Channel Filter Bandwidth, Hi-cut cutoff frequency, Hi-blend cutoff frequency, and Stereo Separation associated with the desired channel. Stereo Separation will only be non-zero if the pilot indicator is set. If SMUTE bit is high, it indicates that audio is soft-muted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Bit 7 6 5 4 CMD 3 2 1 0 0x35 ARG1 0000000 ACFACK ARG Bit Name Function 1 7:1 Reserved Always write 0. 1 0 ACFACK If set clears ACFINT and any ACF interrupts bits. Response Bit 7 6 STATUS CTS ERR XXX RESP1 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT BLEND_INT HIBLEND_INT HICUT_INT XXXXXXX RESP2 SMUTE XXX RESP3 SMATTN[4:0] RESP4 CHANBW[7:0] RESP5 HICUT[7:0] RESP6 HIBLEND[7:0] RESP7 RESP8 PILOT CHBW_INT SOFTMUTE_INT STBLEND[6:0] LOWCUT[7:0] Rev. 0.3 69 AN645 70 RESP Bit Name Function 1 7:5 Reserved 1 4 BLEND_INT If set, indicates that stereo separation has crossed below the blend threshold set by FM_ACF_BLEND_THRESHOLD. 1 3 HIBLEND_INT If set, indicates that the HiBlend cutoff frequency is lower than the threshold as set by FM_ACF_HIBLEND_THRESHOLD. 1 2 HICUT_INT If set, indicates that the HiCut cutoff frequency is lower than the threshold set by FM_ACF_HICUT_THRESHOLD. 1 1 CHBW_INT If set, indicates that the Channel Filter Bandwidth is less than the threshold set by ACF_CHBW_THRESHOLD. 1 0 SOFTMUTE_INT If set, indicates that softmute attenuation has increased above the softmute threshold as set by ACF_SM_THRESHOLD. 2 7:1 Reserved 2 0 SMUTE 3 7:0 SMATTN[7:0] Soft mute attenuation level in dB. Range: 0–31. 4 7:0 CHANBW[7:0] Channel filter bandwidth in kHz. Range: 0–150. 5 7:0 HICUT[7:0] 6 7:0 HIBLEND[7:0] 7 7 PILOT 7 6:0 STBLEND[6:0] Indicates stereo separation. STBLEND will only be non-zero if PILOT = 1. Range 0–100. 7 7:0 LOWCUT[7:0] Lowcut cutoff frequency in units of 10 Hz. Range 1–100. Values may vary. Values may vary. 0 = Audio is not soft muted. 1 = Audio is soft muted. HiCut cutoff frequency in units of 100 Hz. Range: 10–180. HiBlend cutoff frequency in units of 100 Hz. Range: 10–180. 0 = Stereo pilot is not present. 1 = Stereo pilot is present. Rev. 0.3 AN645 Command 0x36 FM_RDS_STATUS The FM_RDS_STATUS command returns RDS information for current channel and reads an entry from the RDS FIFO. RDS information includes synch status, FIFO status, group data (blocks A, B, C, and D), and block errors corrected. Maximum RDS FIFO size is 25 groups. This command clears the RDSINT interrupt bit when INTACK bit in ARG1 is set, and, if MTFIFO is set, the entire RDS receive FIFO is cleared (FIFO is always cleared during FM_TUNE_FREQ or FM_SEEK_START). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Bit 7 6 5 4 3 1 0 STATUS_ONL Y MTFIFO INTACK 0x36 CMD ARG1 00000 ARG Bit Name 1 7:3 Reserved 1 2 2 STATUS_ONLY Function Always write 0. Status Only. Determines if data should be removed from the RDS FIFO. 0 = Data is removed from RDS FIFO, and RDSFIFOUSED decrements by one. Data in BLOCKA, BLOCKB, BLOCKC, BLOCKD, and BLE contain the oldest data in the RDS FIFO. 1 = Data is not removed from RDSFIFO, and the RDSFIFOUSED value stays the same. Data in BLOCKA, BLOCKB, BLOCKC, BLOCKD, BLE, PI, TP, PTY, and status contain the last valid data received for the current station. 1 1 MTFIFO Empty FIFO. The FIFO will always be cleared during FM_TUNE_FREQ and FM_SEEK_START. 0 = If FIFO not empty, read and remove oldest FIFO entry. 1 = Clear RDS Receive FIFO. 1 0 INTACK Interrupt Acknowledge. 0 = RDSINT status preserved. 1 = Clears RDSINT. Rev. 0.3 71 AN645 Response Bit 7 6 STATUS CTS ERR RESP1 XXX RESP2 XXX RESP3 XX 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT X RDSSYNCINT RDSFIFOINT X RDSSYNC RDSFIFOLOST RDSTPPTYINT RDSPIINT TPPTYVALID PIVALID TP PTY[4:0] RESP4 PI[15:8] RESP5 PI[7:0] RESP6 RDSFIFOUSED[7:0] RESP7 BLEA[1:0] BLEB[1:0] BLEC[1:0] RESP8 BLOCKA[15:8] RESP9 BLOCKA[7:0] RESP10 BLOCKB[15:8] RESP11 BLOCKB[7:0] RESP12 BLOCKC[15:8] RESP13 BLOCKC[7:0] RESP14 BLOCKD[15:8] RESP15 BLOCKD[7:0] 72 Rev. 0.3 BLED[1:0] AN645 RESP Bit Name 1 7:5 Reserved 1 4 RDSTPPTYINT 1 3 RDSPIINT 1 = PI (Program Identification) code has changed. 1 2 Reserved Values may vary. 1 1 RDSSYNCINT 1 = RDS synchronization has changed. 1 0 RDSFIFOINT 1 = RDS was received and the RDS FIFO is full or has atleast FM_RDS_INTERRUPT_FIFO_COUNT entries. 2 7:5 Reserved 2 4 TPPTYVALID 2 3 PIVALID 1 = Indicates that PI code is valid. 2 2 Reserved Values may vary. 2 1 RDSSYNC 2 0 RDSFIFOLOST 3 7:6 Reserved 3 5 TP 3 4:0 PTY[4:0] Current channel's PTY code if TPPTYVALID is 1. 4,5 15:0 PI[15:0] Current channel’s PI code if PIVALID is set to 1. 6 7 7 7 7:0 7:6 5:4 3:2 RDSFIFOUSED[7:0] Function Values may vary. 1 = TP (Traffic Program) flag and/or PTY (Program Type) code has changed. Values may vary. 1 = Indicates that TP flag and PTY code are valid. 1 = RDS is currently synchronized. 1 = Indicates that one or more RDS groups have been discarded due to FIFO overrun since last call to FM_RDS_STATUS. Values may vary. Current channel’s TP flag if TPPTYVALID is set to 1. RDS FIFO Used. Number of groups remaining in the RDS FIFO (0 if empty). If non-zero, BLOCKA-BLOCKD contain the oldest FIFO entry and RDSFIFOUSED decrements by one on the next call to RDS_FIFO_STATUS (assuming no RDS data received in the interim). BLEA[1:0] RDS Block A Corrected Errors. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. BLEB[1:0] RDS Block B Corrected Errors. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. BLEC[1:0] RDS Block C Corrected Errors. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. Rev. 0.3 73 AN645 RESP 74 Bit Name Function RDS Block D Corrected Errors. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. 7 1:0 BLED[1:0] 8,9 15:0 BLOCKA[15:0] Block A group data from oldest FIFO entry if STATUSONLY is 0. Last valid Block A data if STATUSONLY is 1. 10,11 15:0 BLOCKB[15:0] Block B group data from oldest FIFO entry if STATUSONLY is 0. Last valid Block A data if STATUSONLY is 1. 12,13 15:0 BLOCKC[15:0] Block C group data from oldest FIFO entry if STATUSONLY is 0. Last valid Block A data if STATUSONLY is 1. 14,15 15:0 BLOCKC[15:0] Block D group data from oldest FIFO entry if STATUSONLY is 0. Last valid Block A data if STATUSONLY is 1. Rev. 0.3 AN645 Command 0x37 FM_RDS_BLOCKCOUNT The FM_RDS_BLOCKCOUNT command returns RDS expected, received, and uncorrectable block statistic information. Reset info by setting CLEAR bit or sending FM_TUNE_FREQ or FM_SEEK_START commands. Once EXPECTED saturates at 65535, all other block count statistics will be frozen until the counts are cleared. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent when in powerup mode. Command Bit 7 6 5 4 3 2 1 0 0x37 CMD 0000000 ARG1 ARG Bit Name 1 7:1 Reserved 1 0 CLEAR CLEAR Function Always write 0. Clears the block counts if set. The current block counts will be reported before they are cleared. Response Bit 7 6 STATUS CTS ERR 5 4 XX 3 2 1 0 RSQINT RDSINT ACFINT STCINT RESP1 XXXXXXXX RESP 2 EXPECTED[15:8] RESP 3 EXPECTED[7:0] RESP 4 RECEIVED[15:8] RESP 5 RECEIVED[7:0] RESP 6 UNCORRECTABLE[15:8] RESP 7 UNCORRECTABLE[7:0] RESP Bit Name 1 7:0 Reserved 2,3 15:0 EXPECTED[15:0] Number of expected RDS blocks. 4,5 15:0 RECEIVED[15:0] Number of received RDS blocks. Under ideal conditions, EXPECTED and RECEIVED would be identical. The difference between these two numbers is the number of blocks lost. 6,7 15:0 Function Values may vary. Number of uncorrectable RDS blocks. These blocks have been received, but were found to have uncorrectable errors. The block UNCORRECTABLE[15:0] error rate (BLER) is calculated by: BLER = (UNCORRECTABLE + (EXPECTED-RECEIVED)) / EXPECTED Rev. 0.3 75 AN645 9.2.2. FM Receiver Properties Property 0x0302 AUDIO_DE_EMPHASIS The AUDIO_DE_EMPHASIS property sets the FM Receive de-emphasis to 50 or 75 μs. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 75 μs. Default: 0 AUDIO_DE_EMPHASIS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x0000 DE_EMPH 0x0000 0 Bit Name Function 15:1 Reserved Always write 0. 0 DE_EMPH Sets the FM Receive de-emphasis to 50 or 75 μs. Default is 75 µs. 0 = 75 µsec 1 = 50 µsec Property 0x0400 FM_SOFT_MUTE_MAX_ATTENUATION The FM_SOFT_MUTE_MAX_ATTENUATION property sets the maximum attenuation in dB that will be applied by the softmute feature. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8 Units: dB FM_SOFT_MUTE_MAX_ATTENUATION 15 76 14 13 12 11 10 9 8 7 6 5 4 3 2 0x000 SMATTN[6:0] 0x000 0x08 Bit Name 15:5 Reserved 4:0 SMATTN[6:0] 1 0 Function Always write 0. Sets the maximum attenuation in dB that will be applied by the softmute feature. Default is 8 dB. Range is 0–63 dB. Rev. 0.3 AN645 Property 0x0401 FM_SOFT_MUTE_TRIGGER_THRESHOLD The FM_SOFT_MUTE_TRIGGER_THRESHOLD property sets the SNR threshold in dB to engage softmute. The CTS bit (and optional interrupt) is set when it is safe to send the next command. If USE_RSSI is set in FM_ACF_CONTROL_SOURCE property, then property 0x0401 refers to RSSI threshold. This property may only be set or read in powerup mode. Default: 8 Units: dB (dBµV if RSSI is used as the control source) FM_SOFT_MUTE_TRIGGER_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 0x00 SMTRGTH[7:0] 0x00 0x08 Bit Name 15:8 Reserved 7:0 SMTRGTH[7:0] 2 1 0 Function Always write 0. Sets the SNR threshold in dB to engage softmute. Default is 8 dB. Range is –127 to 127 dB (dBµV if RSSI is used as the control source). Property 0x0402 FM_SOFT_MUTE_END_THRESHOLD The FM_SOFT_MUTE_END_THRESHOLD property sets the SNR threshold in dB at which softmute attenuation will be set to its maximum value. When the SNR is at this level or lower, the audio attenuation will be set to FM_SOFT_MUTE_MAX_ATTENUATION. The CTS bit (and optional interrupt) is set when it is safe to send the next command. If USE_RSSI is set in the FM_ACF_CONTROL_SOURCE property, then property 0x0402 refers to the RSSI threshold. This property may only be set or read in powerup mode. Default: 0 Units: dB (dBµV if RSSI is used as the control source) FM_SOFT_MUTE_END_THRESHOLD 15 14 13 12 10 9 8 7 6 5 4 3 0x00 SMENDTH[7:0] 0x00 0x00 Bit Name 15:8 Reserved 7:0 11 SMENDTH[7:0] 2 1 0 Function Always write 0. Sets the SNR threshold in dB at which softmute attenuation will be set to its maximum value given by FM_SOFT_MUTE_MAX_ATTENUATION property. Default is 0 dB. Range is –127 to 127 dB (dBµV if RSSI is used as the control source). Rev. 0.3 77 AN645 Property 0x0403 FM_SOFT_MUTE_RELEASE_TIME The FM_SOFT_MUTE_RELEASE_TIME property sets the maximum time in ms it takes to unmute the audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 500 Units: ms FM_SOFT_MUTE_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x01F4 Bit Name 15:0 Function RELEASE[15:0] Sets the maximum time in ms it takes to unmute the audio. Default is 500 ms. Range is 1–32767 ms. Note that there will be 16 ms of filter delay for the RSSI/SNR metric before softmute can engage/disengage. Property 0x0404 FM_SOFT_MUTE_ATTACK_TIME The FM_SOFT_MUTE_ATTACK_TIME property sets the maximum time in ms it takes to mute the audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 120 Units: ms FM_SOFT_MUTE_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0078 Bit 15:0 78 Name ATTACK[15:0] Function Sets the maximum time in ms it takes to mute the audio. Default is 120 ms. Range is 1–32767 ms. Note that there will be 16 ms of filter delay for the RSSI/SNR metric before softmute can engage/disengage. Rev. 0.3 AN645 Property 0x0700 FM_AGC_FE_CONFIG The FM_AGC_FE_CONFIG property specifies the input path for the RF signal and other FE configuration options. This property should only be set before the first tune. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Changes to this property take effect after the next tune is completed. Default: 0 FM_AGC_FE_CONFIG 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0x00 FMLNAZ FMMIX 0x0 Reserved INPUTSELECT[3:0] 0x00 0 0 0x0 0 0x0 0 Bit Name Function 15:9 Reserved Always write 0. 8 FMLNAZ 0 = Normal LNA mode where the LNA input impedance is 50 . 1 = LNA loopthru mode where LNA input impedance is 100 7 FMMIX 6:4 Reserved 3:0 INPUTSELECT[3:0] 0 = Mixer is differential input (FMXIP/FMXIN) 1 = Mixer is single ended (FMXIP) Always write 0. 0 = Received signal comes into FMI pin, out FMO and then the mixer pin. 1 = Received signal comes directly into the mixer. Rev. 0.3 79 AN645 Property 0x0701 FM_AGC_PD_CONFIG The FM_AGC_PD_CONFIG property specifies behavior of the FM peak detectors and attenuators. This property should only be set before the first tune. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Changes to this property take effect after the next tune is completed. Default: 0x0270 FM_AGC_PD_CONFIG 15 14 12 11 10 9 8 7 6 5 4 3 2 1 0 0x0 LNA_MODE 00100 MIXER_PD[2:0] 0x00 LNA_PD[1:0] 0x0 0 00100 0x7 0x00 0x00 Bit Name 15:13 Reserved 12 LNA_MODE 11:7 Reserved 6:4 MIXER_PD[2:0] 3:2 Reserved 1:0 80 13 LNA_PD[1:0] Function Always write 0. LNA_MODE default: 0 This property only used when the LNA gain and one or both of the attenuators are controlled by the same peak detector. 0 = Reduce LNA gain and then attenuate. 1 = Attenuate and then reduce LNA gain. Always write 00100. MIXER_PD[2:0] default: 0x7. 0 = Peak detector not used. 1 = Controls FMAGC1. 2 = Controls FMAGC2. 3 = Controls FMAGC1 and FMAGC2. 4 = Controls LNA gain. 5 = Controls LNA gain and FMAGC1. 6 = Controls LNA gain and FMAGC2. 7 = Controls LNA gain, FMAGC1 and FMAGC2. Always write 0. LNA_PD[1:0] default: 0x0 0 = Peak detector not used 1 = Controls FMAGC1 2 = Controls FMAGC2 3 = Controls FMAGC1 and FMAGC2 Rev. 0.3 AN645 Property 0x0702 FM_LNA_AGC_ATTACK_MS The FM_LNA_AGC_ATTACK_MS property sets the number of milliseconds the wide-band RF high-peak detector must be exceeded before attenuating the appropriate block. The peak detectors are only sampled once every 3 to 5 ms. If the peak detector trips, the internal counter is incremented by 4 ms.The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms FM_LNA_AGC_ATTACK_MS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RF_AGC_ATTACK_MS[15:0] 0x04 Bit 15:0 Name Function RF_AGC_ATTACK_MS[15:0] Number of milliseconds the wideband RF highpeak detector must be exceeded before attenuating the appropriate block. Default is 4 ms. Range is 4–4096 ms. Property 0x0703 FM_LNA_AGC_RELEASE_MS The FM_LNA_AGC_RELEASE_MS property sets the number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. The peak detectors are only sampled once every 3 to 5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 80 Units: ms FM_LNA_AGC_RELEASE_MS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RF_AGC_RELEASE_MS[15:0] 0x50 Bit 15:0 Name Function Number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. RF_AGC_RELEASE_MS[15:0] Default is 80 ms Range is 4–4096 ms. Rev. 0.3 81 AN645 Property 0x0704 FM_LNA_AGC_PD_THRESHOLD The FM_LNA_AGC_PD_THRESHOLD property sets the high threshold and hysteresis for the LNA peak detector. The high threshold sets the level at which the AGC increases attenuation. The hysteresis is how many dB below the high threshold the level must drop before the AGC decreases attenuation. It is possible to decrease the likelihood of intermod break-in by decreasing the peak detector threshold from the default and it is possible to decrease the likelihood of desensitization by increasing the peak detector threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x4F05 FM_LNA_AGC_PD_THRESHOLD 15 14 Bit 15:8 7:0 82 13 12 11 10 9 8 7 6 5 4 3 HIGH[7:0] HYST[7:0] 0x4F 0x05 Name 2 1 0 Function HIGH[7:0] Sets the level in dBµV at which AGC increases attenuation HIGH[7:0] Range: 73–87 73 = 73 dBµV 75 = 75 dBµV 77 = 77 dBµV 79 = 79 dBµV 81 = 81 dBµV 83 = 83 dBµV 85 = 85 dBµV 87 = 87 dBµV HYST[7:0] Sets how many dB below the high threshold the level must drop before the AGC decreases attenuation. HYST[7:0] Range: 3–6 3 = 3 dB 4 = 4 dB 5 = 5 dB 6 = 6 dB Rev. 0.3 AN645 Property 0x0705 FM_MIXER_AGC_ATTACK_MS The FM_MIXER_AGC_ATTACK_MS property sets the number of milliseconds the wideband mixer high-peak detector must be exceeded before attenuating the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms FM_MIXER_AGC_ATTACK_MS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 MIX_AGC_ATTACK_MS[15:0] 0x04 Bit 15:0 Name Function MIX_AGC_ATTACK_MS[15:0] Number of milliseconds the wideband RF highpeak detector must be exceeded before attenuating the appropriate block. Default is 4 ms Range is 4–4096 ms. Property 0x0706 FM_MIXER_AGC_RELEASE_MS The FM_MIXER_AGC_RELEASE_MS property sets the number of milliseconds the wideband mixer low-peak detector must not be exceeded before increasing the gain of the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 80 Units: ms FM_MIXER_AGC_RELEASE_MS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 MIX_AGC_RELEASE_MS[15:0] 0x50 Bit 15:0 Name Function Number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. MIX_AGC_RELEASE_MS[15:0] Default is 80 ms Range is 4–4096 ms. Rev. 0.3 83 AN645 Property 0x0707 FM_MIXER_AGC_PD_THRESHOLD The FM_MIXER_AGC_PD_THRESHOLD property sets the high threshold and hysteresis for the mixer peak detector. The high threshold sets the level at which the AGC increases attenuation. The hysteresis is how many dB below the high threshold the level must drop before the AGC decreases attenuation. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x5503 FM_MIXER_AGC_PD_THRESHOLD 15 14 Bit 15:8 7:0 84 13 12 11 10 9 8 7 6 5 4 3 HIGH[7:0] HYST[7:0] 0x55 0x03 Name 2 1 0 Function HIGH[7:0] Sets the level in dBµV at which AGC increases attenuation. HIGH[7:0]: Range 79–93. 79 = 79 dBµV. 81 = 81 dBµV. 83 = 83 dBµV. 85 = 85 dBµV. 87 = 87 dBµV. 89 = 89 dBµV. 91 = 91 dBµV. 93 = 93 dBµV. HYST[7:0] Sets how many dB below the high threshold the level must drop before the AGC decreases attenuation. HYST[7:0] - Range: 3–6. 3 = 3 dB. 4 = 4 dB. 5 = 5 dB. 6 = 6 dB. Rev. 0.3 AN645 Property 0x0710 FM_AGC_OVERRIDE The FM_AGC_OVERRIDE property overrides the AGC setting by disabling the AGC and forcing the gain to be maximum. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 FM_AGC_OVERRIDE 15 14 13 12 11 10 9 7 6 5 4 3 2 1 0x000 AGC_OVERRIDE[5:0] 0x000 0 Bit Name 15:6 Reserved 5:0 8 0 Function Always write 0. AGC_OVERRIDE selects whether the AGC is enabled or disabled. 0 = AGC is enabled. 0x3F = AGC is disabled and set to maximum gain. AGC_OVERRIDE[5:0] Property 0x1100 FM_SEEK_BAND_BOTTOM The FM_SEEK_BAND_BOTTOM property sets the bottom of the FM band for seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 87.5 MHz. Default: 8750 Units: 10 kHz FM_SEEK_BAND_BOTTOM 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FMSKFREQL[15:0] 0x222E Bit 15:0 Name FMSKFREQL[15:0] Function Sets the bottom of the FM band for seek. Default is 8750. Range: 6400–10800, 64.0 MHz to 108.0 MHz. Range: 8750–10790, Worldwide FM excluding Japan. Range: 6580–7400, OIRT FM. Range: 7600–9000, Japan FM. Rev. 0.3 85 AN645 Property 0x1101 FM_SEEK_BAND_TOP The FM_SEEK_BAND_TOP property sets the top of the FM band for seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 107.9 MHz Default: 10790 Units: 10 kHz FM_SEEK_BAND_TOP 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FMSKFREQH[15:0] 0x2A26 Bit Name 15:0 Function FMSKFREQH[15:0] Sets the top of the FM band for seek. Default is 10790. Range: 6400–10800, 64.0 MHz to 108.0 MHz. Range: 8750–10790, Worldwide FM excluding Japan. Range: 6580–7400, OIRT FM. Range: 7600–9000, Japan FM. Property 0x1102 FM_SEEK_FREQUENCY_SPACING The FM_SEEK_FREQUENCY_SPACING property selects frequency spacing for FM seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 100 kHz. Default: 10 Units: 10 kHz FM_SEEK_FREQUENCY_SPACING 15 86 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0x000 FMSKSPACE[4:0] 0x000 0x0A Bit Name 15:5 Reserved 4:0 FMSKSPACE[4:0] Rev. 0.3 0 Function Always write 0. Selects frequency spacing for FM seek. Default is 10. Range is 1–31. AN645 Property 0x1200 FM_RSQ_INTERRUPT_SOURCE The FM_RSQ_INTERRUPT_SOURCE property configures interrupt related to Received Signal Quality metrics. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 0. Default: 0 FM_RSQ_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 0x00 MULTHINT MULTLINT 0x00 0 0 5 4 3 2 0 SNRHINT SNRLINT 0 0 0 1 0 RSSIHINT RSSILINT 0 0 Bit Name Function 15:8 Reserved 7 MULTHINT 0: Disable Interrupt. 1:Enable interrupt if Multipath level goes above the threshold set by FM_RSQ_MULTIPATH_HIGH_THRESHOLD. 6 MULTLINT 0: Disable Interrupt. 1: Enable interrupt if Multipath level falls below the threshold set by FM_RSQ_MULTIPATH_LOW_THRESHOLD. 5:4 Reserved Always write 0. 3 SNRHINT 0: Disable Interrupt. 1: Enable interrupt if SNR goes above the threshold set by FM_RSQ_SNR_HIGH_THRESHOLD. 2 SNRLINT 0: Disable Interrupt. 1: Enable interrupt if SNR falls below the threshold set by FM_RSQ_SNR_LOW_THRESHOLD. 1 RSSIHINT 0: Disable Interrupt. 1: Enable interrupt if RSSI goes above the threshold set by FM_RSQ_RSSI_HIGH_THRESHOLD. 0 RSSILINT 0: Disable Interrupt. 1: Enable interrupt if RSSI falls below the threshold set by FM_RSQ_RSSI_LOW_THRESHOLD. Always write 0. Rev. 0.3 87 AN645 Property 0x1201 FM_RSQ_SNR_HIGH_THRESHOLD The FM_RSQ_SNR_HIGH_THRESHOLD property sets the high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Units: dB FM_RSQ_SNR_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 0x00 SNRH[7:0] 0x00 0x7F Bit Name 15:8 Reserved 7:0 SNRH [7:0] 2 1 0 Function Write 0 for (+) values and 0xFF for (–) values. Sets the high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. Default is 127 dB. Range is –128 to 27 in steps of 1 dB. Property 0x1202 FM_RSQ_SNR_LOW_THRESHOLD The FM_RSQ_SNR_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if the SNR is below this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –128 Units: dB FM_RSQ_SNR_LOW_THRESHOLD 15 88 14 13 12 11 10 9 8 7 6 5 4 3 0xFF SNRL[7:0] 0xFF 0x80 Bit Name 15:8 Reserved 7:0 SNRL [7:0] 2 1 0 Function Write 0 for (+) values and 0xFF for (–) values. Sets low threshold, which triggers the RSQ interrupt if the SNR is below this threshold. Default is –128 dB. Range is –128 to 127 in steps of 1 dB. Rev. 0.3 AN645 Property 0x1203 FM_RSQ_RSSI_HIGH_THRESHOLD The FM_RSQ_RSSI_HIGH_THRESHOLD property sets the high threshold, which triggers the RSQ interrupt if RSSI is above this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Units: dBµV FM_RSQ_RSSI_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 0x00 0x00 Bit Name 15:8 Reserved 7:0 RSSIH [7:0] 4 3 2 1 0 RSSIH[7:0] 0x7F Function Write 0 for (+) values and 0xFF for (–) values. Sets high threshold, which triggers the RSQ interrupt if the RSSI is above this threshold. Default is 127 dBµV. Range is –128 to 127 in steps of 1 dB. Property 0x1204 FM_RSQ_RSSI_LOW_THRESHOLD The FM_RSQ_RSSI_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if the RSSI is below this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –128 Units: dBµV FM_RSQ_RSSI_LOW_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 0xFF RSSIL[7:0] 0xFF 0x80 Bit Name 15:8 Reserved 7:0 RSSIL [7:0] 2 1 0 Function Write 0 for (+) values and 0xFF for (–) values. Sets low threshold, which triggers the RSQ interrupt if the RSSI is below this threshold. Default is –128 dBµV. Range is –128 to 127 in steps of 1 dB. Rev. 0.3 89 AN645 Property 0x1207 FM_RSQ_MULTIPATH_HIGH_THRESHOLD The FM_RSQ_MULTIPATH_HIGH_THRESHOLD property sets the high threshold, which triggers the RSQ interrupt if Multipath is above this threshold. Multipath is a measure of AM modulation and can exceed 100%. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 FM_RSQ_MULTIPATH_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 0x000 MULTH[6:0] 0x000 0x7F Bit Name 15:7 Reserved 6:0 MULTH [6:0] 2 1 0 Function Always write 0. Sets the high threshold, which triggers the RSQ interrupt if Multipath is above this threshold. Default is 127. Range is 0–127. Property 0x1208 FM_RSQ_MULTIPATH_LOW_THRESHOLD The FM_RSQ_MULTIPATH_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if Multipath is below this threshold. Multipath is a measure of AM modulation and can exceed 100%. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 FM_RSQ_MULTIPATH_LOW_THRESHOLD 15 90 14 13 12 11 10 9 8 7 6 5 4 3 0x000 MULTL[6:0] 0x000 0x00 Bit Name 15:7 Reserved 6:0 MULTL[6:0] 2 1 0 Function Always write 0. Sets low threshold, which triggers the RSQ interrupt if Multipath is below this threshold. Default is 0. Range is 0–127. Rev. 0.3 AN645 Property 0x1300 FM_ACF_INTERRUPT_SOURCE The FM_ACF_INTERRUPT_SOURCE property enables the ACF interrupt sources. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 FM_ACF_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 0x000 BLEND_INT HIBLEND_INT HICUT_INT 0x000 0 0 0 Bit Name 15:5 Reserved 4 BLEND_INT 3 HIBLEND_INT 1 0 CHBW_INT SOFTMUTE_INT 0 0 Function Always write 0. When set, enables the blend interrupt. Default is 0. 0 = The blend interrupt is disabled. 1 = The blend interrupt is enabled. When set, enables the Hi-blend Interrupt. Default is 0. 0 = The Hi-blend interrupt is disabled. 1 = The Hi-blend interrupt is enabled. 2 HICUT_INT When set, enables the Hi-cut interrupt. Default is 0. 0 = The Hi-cut interrupt is disabled. 1 = The Hi-cut interrupt is enabled. 1 CHBW_INT When set, enables the Channel Filter Bandwidth Interrupt. Default is 0. 0 = The Channel Filter Bandwidth interrupt is disabled. 1 = The Channel Filter Bandwidth interrupt is enabled. 0 SOFTMUTE_INT When set, enables the blend interrupt. Default is 0. 0 = The softmute interrupt is disabled. 1 = The softmute interrupt is enabled. Rev. 0.3 91 AN645 Property 0x1301 FM_ACF_SM_THRESHOLD The FM_ACF_SM_THRESHOLD property sets the softmute interrupt threshold in dB. When softmute attenuation rises above the level set by this property and the SOFTMUTE_INT interrupt is enabled through the FM_ACF_INTERRUPT_SOURCE property, the SOFTMUTE_INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in the powerup mode. Default: 31 Units: dB FM_ACF_SM_THRESHOLD 15 13 12 11 10 9 8 7 6 5 4 3 2 1 0x000 SMATTN_THRESH[4:0] 0x000 0x1F Bit Name 15:5 Reserved 4:0 92 14 SMATTN_THRESH[4:0] 0 Function Always write 0. Softmute interrupt threshold in dB, which triggers the softmute interrupt when the softmute attenuation rises above this level. Default is 31 dB Range is 0–31 dB. Rev. 0.3 AN645 Property 0x1302 FM_ACF_CHBW_THRESHOLD The FM_ACF_CHBW_THRESHOLD property sets the Channel Filter Bandwidth interrupt threshold in units of kHz. When the channel filter bandwidth falls below this threshold and the CHBW_INT interrupt is enabled through the FM_ACF_INTERRUPT_SOURCE property, the CHBW_INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: kHz FM_ACF_CHBW_THRESHOLD 15 14 13 12 10 9 8 7 6 5 4 3 2 0x00 CHBW_THRESH[7:0] 0x00 0x00 Bit Name 15:8 Reserved 7:0 11 1 0 Function Always write 0. Channel Filter Bandwidth interrupt threshold in units of kHz, which triggers the Channel Filter Bandwidth Interrupt when the channel filter bandwidth falls CHBW _THRESH[7:0] below this threshold. Default is 0 kHz Range is 0–255 kHz. Rev. 0.3 93 AN645 Property 0x1303 FM_ACF_HICUT_THRESHOLD The FM_ACF_HICUT_THRESHOLD property sets the Hi-cut interrupt threshold in units of 100 Hz. When the Hicut cutoff frequency falls below this threshold and the HICUT_INT interrupt is enabled through the FM_ACF_INTERRUPT_SOURCE property, the HICUT_INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: 100 Hz FM_ACF_HICUT_THRESHOLD 15 13 12 11 10 9 8 7 6 5 4 3 2 0x00 HICUT_THRESH[7:0] 0x00 0x00 Bit Name 15:8 Reserved 7:0 94 14 HICUT_THRESH[7:0] 1 0 Function Always write 0. Hi-cut interrupt threshold in units of 100 Hz, which triggers the Hi-cut Interrupt when the Hi-cut cutoff frequency falls below this threshold. Default is 0. Range is 0–200. Rev. 0.3 AN645 Property 0x1304 FM_ACF_HIBLEND_THRESHOLD The FM_ACF_HIBLEND_THRESHOLD property sets the HiBlend interrupt threshold in units of 100 Hz. When the Hi-blend cutoff frequency falls below this threshold and the HIBLEND_INT interrupt is enabled through the FM_ACF_INTERRUPT_SOURCE property, the HIBLEND_INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: 100 Hz FM_ACF_HIBLEND_THRESHOLD 15 14 13 12 10 9 8 7 6 5 4 3 2 0x00 HIBLEND_THRESH[7:0] 0x00 0x00 Bit Name 15:8 Reserved 7:0 11 1 0 Function Always write 0. Hi-blend interrupt threshold in units of 100 Hz, which triggers the Hi-blend Interrupt when the Hi-blend cutoff frequency falls below this threshold. HIBLEND_THRESH[7:0] Default is 0. Range is 0–200. Rev. 0.3 95 AN645 Property 0x1305 FM_ACF_BLEND_THRESHOLD The FM_ACF_BLEND_THRESHOLD property sets the interrupt trigger threshold for stereo blend. The threshold is expressed as a percentage in terms of L minus R (L – R) gain factor K. When the L–R gain falls below this threshold and the BLEND_INT is enabled through the FM_ACF_INTERRUPT_SOURCE property, the BLEND_INT will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Note: Stereo Separation S = (1 + K) / (1 – K), where K is the L minus R gain factor. Stereo separation of 1 implies mono mode and stereo separation of >1 implies that the part is in stereo with up to 20 log(S) dB of stereo separation. This property expresses the threshold value of K as a percentage. For example, value 0x0032 = a K of 50%, or a stereo separation of S = (1.5 / 0.5) = 3. The interrupt would then trigger at 20 log(3) = 9.5 dB of stereo separation. Default: 0 Units: % L-R gain FM_ACF_BLEND_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 0x000 BLEND_THRESH[6:0] 0x000 0x00 1 0 Bit Name 15:7 Reserved Always write 0. 6:0 BLEND_ THRESH [6:0] Stereo Blend Interrupt threshold in units of % L-R gain, which triggers the Blend threshold interrupt when L-R gain falls below this threshold. Default is 0%. Range is 0–100%. 96 Function Rev. 0.3 AN645 Property 0x1306 FM_ACF_CONTROL_SOURCE The FM_ACF_CONTROL_SOURCE property determines the controlling metric for ACF features. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 1 FM_ACF_CONTROL_SOURCE 15 14 Bit Name 15:1 Reserved 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x0000 AFC_SM 0 RSSI_SM 0x0000 0 0 1 Function Always write 0. default: 0. When set, softmute will be triggered by an AFC rail. 2 AFC_SM 0 = Do not use AFC rail to force a softmute. 1 = Use AFC rail to force a softmute. 1 Reserved Always write 0. 0 RSSI_SM default: 1. When set, RSSI will be used instead of SNR as the controlling metric for softmute. 0 = Use SNR as the controlling metric for softmute. 1 = Use RSSI as the controlling metric for softmute. Rev. 0.3 97 AN645 Property 0x2000 FM_VALID_MAX_TUNE_ERROR The FM_VALID_MAX_TUNE_ERROR property sets the maximum freq error allowed in units of 2 ppm before setting the AFC rail indicator (AFCRL). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 75 (150 ppm) Units: 2 ppm FM_VALID_MAX_TUNE_ERROR 15 14 13 12 11 10 9 8 7 6 5 4 3 2 0x00 FMMAXTUNEERR[7:0] 0x00 0x4B Bit Name 15:8 Reserved 7:0 FMMAXTUNEERR [7:0] 1 0 Function Always write 0. Sets the maximum freq error allowed in units of 2 ppm before setting the AFC rail indicator (AFCRL). Default is 75. Range is 0–126. Property 0x2001 FM_VALID_RSSI_TIME The FM_VALID_RSSI_TIME property sets the amount of time in milliseconds to allow the RSSI metric to settle before evaluating. This parameter is valid only if TUNEMODE[1:0] (FM_TUNE_FREQ) is set to 0. The minimum RSSI settling delay is 3 milliseconds. The reliability of the valid bit for identifying valid stations relies on this parameter being set properly. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 6 Units: ms FM_VALID_RSSI_TIME 15 98 14 13 12 11 10 9 8 7 6 5 4 3 0x00 SSIVALTIME[7:0] 0x00 0x06 Bit Name 15:8 Reserved 7:0 SSIVALTIME[7:0] 2 1 0 Function Always write 0. Validation time in milliseconds. Default is 6 ms. Range is 3–63 ms. Rev. 0.3 AN645 Property 0x2002 FM_VALID_SNR_TIME The FM_VALID_SNR_TIME property sets the amount of time in milliseconds to allow the SNR metric to settle before evaluating. This parameter is valid only if TUNEMODE[1:0] (FM_TUNE_FREQ) is set to 0. The minimum SNR settling delay is 4 ms. The reliability of the valid bit for identifying valid stations relies on this parameter being set properly. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 18 Units: ms FM_VALID_SNR_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 0x00 SNRVALTIME[7:0] 0x00 0x12 Bit Name 15:8 Reserved 7:0 SNRVALTIME[7:0] 2 1 0 Function Always write 0. Validation time in milliseconds. Default is 18 ms. Range is 4–63 ms. Property 0x2003 FM_VALID_SNR_THRESHOLD The FM_VALID_SNR_THRESHOLD property sets the SNR threshold for a valid FM Seek/Tune. If the desired channel SNR is above this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8 Units: dB FM_VALID_SNR_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 0x00 FMVALSNR[7:0] 0x00 0x08 Bit Name 15:8 Reserved 7:0 FMVALSNR [7:0] 2 1 0 Function Write 0 for (+) values and 0xFF for (–) values. Sets the SNR threshold for a valid FM Seek/Tune. Default is 8 dB. Range is –128 to 127 in steps of 1 dB. –128 = SNR is not used as a criterion in determining the validity of a station. Rev. 0.3 99 AN645 Property 0x2004 FM_VALID_RSSI_THRESHOLD The FM_VALID_RSSI_THRESHOLD property sets the RSSI threshold for a valid FM Seek/Tune. If the desired channel RSSI is above this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 12 Units: dBµV FM_VALID_RSSI_THRESHOLD 15 14 13 12 10 9 8 7 6 5 4 3 0x00 FMVALRSSI[7:0] 0x00 0x0C Bit Name 15:8 Reserved 7:0 11 2 1 0 Function Always write 0. FMVALRSSI[7:0] Sets the RSSI threshold for a valid FM Seek/Tune. Default is 12 dBµV. Range is –128 to 127 in steps of 1 dB. –128 = RSSI is not used as a criterion in determining the validity of a station. Property 0x200A FM_VALID_ASSI_THRESHOLD The FM_VALID_ASSI_THRESHOLD property sets the ASSI threshold for valid FM Seek/Tune. If the desired channel ASSI is below this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x503C Units: ms FM_VALID_ASSI_THRESHOLD 15 14 13 12 11 9 8 7 6 5 4 3 2 FMVALASSI200[6:0] 0 FMVALASSI100[6:0] 0x50 0 0x3C Bit Name 15 Reserved 14:8 FMVALASSI200[6:0] 7 Reserved 6:0 FMVALASSI100[6:0] 100 10 Function Always write 0. Sets the ASSI200 threshold for valid FM Seek/Tune. Default is 80 dB. Range is 0 to 127 dB. Always write 0. Sets the max(HASSI,LASSI) threshold for valid FM Seek/Tune. Default is 60 dB. Range is 0 to 127 dB. Rev. 0.3 1 0 AN645 Property 0x2200 FM_CHBW_SQ_MIN_MAX The FM_CHBW_SQ_MIN_MAX property sets the maximum and minimum channel filter bandwidth in kHz based on RSSI. To force a given channel filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x9637 Units: kHz FM_CHBW_SQ_MIN_MAX 15 14 13 12 11 10 9 8 7 6 5 4 3 MAX[7:0] MIN[7:0] 0x96 0x37 Bit Name 15:8 MAX [7:0] Sets the maximum channel filter bandwidth in kHz. Default is 150 kHz Range is 1–150 kHz. 7:0 MIN [7:0] Sets the minimum channel filter bandwidth in kHz. Default is 55 kHz. Range is 1–150 kHz. 2 1 0 Function Property 0x2201 FM_CHBW_SQ_HIGH_THRESHOLD The FM_CHBW_SQ_HIGH_THRESHOLD property sets the RSSI/deviation threshold for maximum channel filter bandwidth. This engine is only enabled when RSSI is above the FM_CHBW_WEAKSIG_THR. If the instantaneous RSSI is greater than or equal to the programmed RSSI high threshold then the channel filter bandwidth will be set to the maximum value programmed through Property 0x2200. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 12 Units: dBµV FM_CHBW_SQ_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RSSIMAX[15:0] 0x000C Bit 15:0 Name RSSIMAX[15:0] Function Sets the RSSI threshold for maximum channel filter bandwidth. Default is 12 dBµV Range is –128 to 127 dBµV. Rev. 0.3 101 AN645 Property 0x2202 FM_CHBW_SQ_LOW_THRESHOLD The FM_CHBW_SQ_LOW_THRESHOLD property sets the RSSI threshold for minimum channel filter bandwidth. This engine is only enabled when RSSI is above the FM_CHBW_WEAKSIG_THR. If the instantaneous RSSI is less than or equal to the programmed RSSI low threshold then the channel filter bandwidth will be set to the minimum value programmed through Property 0x2200. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –4 Units: dBµV FM_CHBW_SQ_LOW_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RSSIMIN[15:0] 0xFFFC Bit Name Function 15:0 RSSIMIN[15:0] Sets the RSSI threshold for minimum channel filter bandwidth. Default is –4 dBµV Range is 128 to –127 dBµV. Property 0x2203 FM_CHBW_SQ_WIDENING_TIME The FM_CHBW_SQ_WIDENING_TIME property sets the channel filter bandwidth widening time based on RSSI. This engine is only enabled when RSSI is above the FM_CHBW_WEAKSIG_THR. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_CHBW_SQ_WIDENING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 WIDENING_TIME[15:0] 0x0010 Bit 15:0 102 Name WIDENING_TIME[15:0] Function Sets the RSSI based channel filter bandwidth widening time. Default is 16 ms Range is 1–32767 ms. Rev. 0.3 0 AN645 Property 0x2204 FM_CHBW_SQ_NARROWING_TIME The FM_CHBW_SQ_NARROWING_TIME property sets the channel filter bandwidth narrowing time based on RSSI. This engine is only enabled when RSSI is above the FM_CHBW_WEAKSIG_THR. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 2048 Units: ms FM_CHBW_SQ_NARROWING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 NARROWING_TIME[15:0] 0x0800 Bit 15:0 Name NARROWING_TIME[15:0] Function Sets the RSSI based channel filter bandwidth narrowing time. Default is 2048 ms. Range is 1–32767 ms. Rev. 0.3 103 AN645 Property 0x2205 FM_CHBW_ASSI_MIN_MAX The FM_CHBW_ASSI_MIN_MAX property sets the maximum and minimum Channel Filter Bandwidth in kHz based on 100 kHz blocker delta (difference between HASSI and LASSI). To force a given channel filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x9623 Units: kHz FM_CHBW_ASSI_MIN_MAX 15 14 13 12 11 10 9 8 7 6 5 4 3 MAX[7:0] MIN[7:0] 0x96 0x23 Bit Name 15:8 MAX [7:0] Sets the maximum channel filter bandwidth in kHz. Default is 150 kHz. Range is 1–150 kHz. 7:0 MIN [7:0] Sets the minimum channel filter bandwidth in kHz. Default is 35 kHz. Range is 1–150 kHz. 2 1 0 Function Property 0x2206 FM_CHBW_ASSI_LOW_THRESHOLD The FM_CHBW_ASSI_LOW_THRESHOLD property sets the 100 kHz blocker delta (difference between HASSI and LASSI) threshold for maximum channel filter bandwidth. If the 100 kHz blocker delta is less than or equal to the programmed ASSI low threshold, then the channel filter bandwidth will be set to the maximum value programmed through Property 0x2205. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 7 Units: dB FM_CHBW_ASSI_LOW_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 ASSIMIN[15:0] 0x0007 Bit 15:0 104 Name ASSIMIN[15:0] Function Sets the 100 kHz blocker delta threshold for maximum channel filter bandwidth. Default is 7 dB. Range is –128 to 127 dB. Rev. 0.3 0 AN645 Property 0x2207 FM_CHBW_ASSI_HIGH_THRESHOLD The FM_CHBW_ASSI_HIGH_THRESHOLD property sets the 100 kHz blocker delta (difference between HASSI and LASSI) threshold for minimum channel filter bandwidth. If the 100 kHz blocker delta is greater than the programmed ASSI high threshold, then the channel filter bandwidth will be set to the minimum value programmed through Property 0x2205. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 20 Units: dB FM_CHBW_ASSI_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ASSIMAX[15:0] 0x0014 Bit Name 15:0 Function ASSIMAX[15:0] Sets the 100 kHz blocker delta threshold for minimum channel filter bandwidth. Default is 20 dB. Range is –128 to 127 dB. Property 0x2208 FM_CHBW_ASSI_WIDENING_TIME The FM_CHBW_ASSI_WIDENING_TIME property sets the channel filter bandwidth widening time based on the 100 kHz blocker delta (difference between HASSI and LASSI). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 3200 Units: ms FM_CHBW_ASSI_WIDENING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 WIDENING_TIME[15:0] 0x0C80 Bit 15:0 Name Function Sets the 100 kHz blocker delta based channel filter bandwidth widening time. WIDENING_TIME[15:0] Default is 3200 ms. Range is 1–32767 ms. Rev. 0.3 105 AN645 Property 0x2209 FM_CHBW_ASSI_NARROWING_TIME The FM_CHBW_ASSI_NARROWING_TIME property sets the channel filter bandwidth narrowing time based on the 100 kHz blocker delta (difference between HASSI and LASSI). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 320 Units: ms FM_CHBW_ASSI_NARROWING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 NARROWING_TIME[15:0] 0x0140 Bit Name 15:0 Function NARROWING_TIME[15:0] Sets the 100 kHz blocker delta based channel filter bandwidth narrowing time. Default is 320 ms. Range is 1–32767 ms. Property 0x220A FM_CHBW_ASSI200_MIN_MAX The FM_CHBW_ASSI200_MIN_MAX property sets the maximum and minimum channel filter bandwidth in kHz based on 200 kHz blocker strength. To force a given channel filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x9650 Units: kHz FM_CHBW_ASSI200_MIN_MAX 15 14 12 11 10 9 8 7 6 5 4 3 MAX[7:0] MIN[7:0] 0x96 0x50 2 1 Bit Name 15:8 MAX[7:0] Sets the maximum channel filter bandwidth in kHz. Default is 150 kHz. Range is 1–150 kHz. MIN[7:0] Sets the minimum channel filter bandwidth in kHz. Default is 80 kHz. Range is 1–150 kHz. 7:0 106 13 Function Rev. 0.3 0 AN645 Property 0x220B FM_CHBW_ASSI200_LOW_THRESHOLD The FM_CHBW_ASSI200_LOW_THRESHOLD property sets the 200 kHz blocker strength threshold for maximum channel filter bandwidth. If the 200 kHz blocker strength is less than or equal to the programmed ASSI200 low threshold, then the channel filter bandwidth will be set to the maximum value programmed through Property 0x220A. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: –10 Units: dB relative to desired channel RSSI FM_CHBW_ASSI200_LOW_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ASSI200MIN[7:0] 0xFFF6 Bit Name 15:0 Function Sets the 200 kHz blocker strength threshold for maximum channel filter bandwidth. Default is –10 dB (relative to desired channel RSSI) Range is –128 to 127 dBr. ASSI200MIN[15:0] Property 0x220C FM_CHBW_ASSI200_HIGH_THRESHOLD The FMCHBW_ASSI200_HIGH_THRESHOLD property sets the 200 kHz blocker strength threshold for minimum channel filter bandwidth. If the 200 kHz blocker strength is greater than the programmed ASSI200 high threshold, then the channel filter bandwidth will be set to the minimum value programmed through Property 0x220A. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 10 Units: dB relative to desired channel RSSI FM_CHBW_ASSI200_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ASSI200MAX[7:0] 0x000A Bit 15:0 Name ASSI200MAX[15:0] Function Sets the 200 kHz blocker strength threshold for maximum channel filter bandwidth. Default is 10 dB (relative to desired channel RSSI) Range is –128 to 127 dBr. Rev. 0.3 107 AN645 Property 0x220D FM_CHBW_ASSI200_WIDENING_TIME The FM_CHBW_ASSI200_WIDENING_TIME property sets the channel filter bandwidth widening time based on the 200 kHz blocker strength. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 3200 Units: ms FM_CHBW_ASSI200_WIDENING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 WIDENING_TIME[15:0] 0x0C80 Bit Name 15:0 Function Sets the 200 kHz blocker strength based channel filter bandwidth widening time. Default is 3200 ms. Range is 1–32767 ms. WIDENING_TIME[15:0] Property 0x220E FM_CHBW_ASSI200_NARROWING_TIME The FM_CHBW_ASSI200_NARROWING_TIME property sets the channel filter bandwidth narrowing time based on the 200 kHz blocker strength. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 320 Units: ms FM_CHBW_ASSI200_NARROWING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 NARROWING_TIME[15:0] 0x0140 Bit 15:0 108 Name Function NARROWING_TIME[15:0] Sets the 200 kHz blocker strength based channel filter bandwidth narrowing time. Default is 320 ms. Range is 1–32767 ms. Rev. 0.3 AN645 Property 0x220F FM_CHBW_WEAKSIG_THR The FM_CHBW_WEAKSIG_THR property sets the RSSI value at which the engine will engage (LOW) and disengage (HIGH) for the weak signal channel filter bandwidth engine. Default: 0x100D FM_CHBW_WEAKSIG_THR 15 14 13 12 11 10 9 8 7 6 5 4 3 2 HIGH[7:0] LOW[7:0] 0x10 0x0D 1 0 Bit Name Function 15:8 HIGH[7:0] When RSSI is above this value, the weak signal channel filter bandwidth engine disengages. Default: 0x10. 7:0 LOW[7:0] When RSSI is below this value, the weak signal channel filter bandwidth engine engages. Default: 0x0D. Property 0x3105 FM_LOWCUT_MIN_FREQ The FM_LOWCUT_MIN_FREQ property sets the minimum cutoff frequency. The LowCut tracks the HICUT engine; therefore, thresholds are programmed in HICUT threshold properties (0x3600, 0x3604, 0x3608, 0x360C, 0x3610, 0x3614) and the HIBLEND threshold properties (0x3700, 0x3740, 0x3708, 0x370C, 0x3710, 0x3714). Setting the property to 0 disables LowCut. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: Hz FM_LOWCUT_MIN_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MIN[15:0] 0x0000 Bit 15:0 Name FREQ_MIN[15:0] Function Sets the minimum LOW-CUT cutoff frequency in Hz. Default is disabled. Range is 8–1000 Hz. 0 = Disabled. Rev. 0.3 109 AN645 Property 0x3106 FM_LOWCUT_MAX_FREQ The FM_LOWCUT_MAX_FREQ property sets the maximum cutoff frequency. The LowCut tracks the HICUT engine, therefore thresholds are programmed in HICUT threshold properties (0x3600, 0x3604, 0x3608, 0x360C, 0x3610, 0x3614) and the HIBLEND threshold properties (0x3700, 0x3740, 0x3708, 0x370C, 0x3710, 0x3714). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: Hz FM_LOWCUT_MIN_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MAX[15:0] 0x0000 Bit 15:0 110 Name Function FREQ_MAX[15:0] Sets the maximum LOW-CUT cutoff frequency in Hz. Note that if property 0x3105 (FM_LOWCUT_MIN_FREQ) is nonzero, this property must be set to a value no less than property 0x3105. Default is 0 Hz. Range is 0–1000 Hz. Rev. 0.3 AN645 Property 0x3300 FM_IBOC_CONTROL (Si4777 Only) The FM_IBOC_CONTROL property is the control property for IBOC Blend. DIGITAL_IO_INPUT_SAMPLE_RATE and DIGITAL_IO_INPUT_FORMAT must be configured before IBOC Blend will function. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 FM_IBOC_CONTROL 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x00 FORCE 0x00 ENABLE 0x00 0 0x00 0 Bit Name 15:9 Reserved Function Always write 0. Forces IBOC Blend. Default is 0. 0 = Do not force IBOC blend. The audio source is determined by the IBOC control pin. 1 = Force IBOC blend. The audio is sourced from the IBOC system 8 FORCE 7:1 Reserved Always write 0. 0 ENABLE ENABLE - IBOC Blend Enable. Default is 0. 0 = The IBOC Blend system is disabled. 1 = The IBOC Blend system is enabled. Property 0x3301 FM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME (Si4777 Only) The FM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME property sets the crossfade time between full analog and full HD Digital audio in ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 1000 Units: ms FM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 TIME[15:0] 0x03E8 Bit Name 15:0 TIME[15:0] Function Sets the full analog to full digital crossfade time in ms. Default is 1000 ms. Range is 0–22000 ms. Rev. 0.3 111 AN645 Property 0x3302 FM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME (Si4777 Only) The FM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME property sets the crossfade time from full HD Digital to full analog audio in ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 1000 Units: ms FM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 TIME[15:0] 0x03E8 Bit Name Function 15:0 TIME[15:0] Sets the full digital to full analog crossfade time in ms. Default is 1000 ms. Range is 0–22000 ms. Property 0x3303 FM_IBOC_DYNAMIC_GAIN (Si4777 Only) The FM_IBOC_DYNAMIC_GAIN property sets the digital audio dynamic linear scaling factor. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x007F FM_IBOC_DYNAMIC_GAIN 15 14 12 11 10 9 8 7 6 5 4 3 0x00 DGAIN[7:0] 0x00 0x7F Bit Name 15:8 Reserved 7:0 112 13 DGAIN[7:0] Function Always write 0. Station dependent linear scaling factor in Q7 format. Default is 0x7F. Range is 0–0x7F. Rev. 0.3 2 1 0 AN645 Property 0x3304 FM_IBOC_STATIC_GAIN (Si4777 Only) The FM_IBOC_STATIC_GAIN property sets the digital audio static linear gain factor. Reverse the sign of this number to obtain a 180 degree phase shift. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 0x0100 FM_IBOC_STATIC_GAIN 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 SGAIN[15:0] 0x0100 Bit Name Function 15:0 SGAIN[15:0] Static linear gain factor in Q7.8 format. Default is 0x0100. Range is 0x8000–0x7FFF. Property 0x3400 FM_MULT_EQ_CTL The FM_MULT_EQ_CTL property controls the multipath channel equalizer. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 5121 FM_MULT_EQ_CTL 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x00 NUM_TAPS[4:0] 0x00 MULT_EQ_CTL[1:0] 0x00 0x14 0x00 0x1 Bit Name 15:13 Reserved 12:8 NUM_TAPS[4:0] 7:2 Reserved 1:0 MULT_EQ_CTL[1:0] Function Always write 000. Number of taps in the multipath equalizer. Range 1-20. For automatic selection, use 0. Always write 000000. Controls the Multipath channel equalizer. Default is 1 0 = Equalizer OFF 1 = Equalizer ON Rev. 0.3 113 AN645 Property 0x3401 FM_EQ_NOISE_DISABLE_MULT_EQ The FM_EQ_NOISE_DISABLE_MULT_EQ property sets the RSSI threshold below which the channel equalizer will use noise measurements to enable/disable the channel equalizer. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xFC81 FM_EQ_NOISE_DISABLE_MULT_EQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 MULT_EQ_ON_LEVEL[7:0] MULT_EQ_OFF_LEVEL[7:0] 0xFC 0x81 1 0 Bit Name Function 15:8 MULT_EQ_ON_LEVEL[7:0] RSSI level above which noise measurements will not be used to enable/disable the equalizer. Default: –4 (0xFC). 7:0 MULT_EQ_OFF_LEVEL[7:0] RSSI level below which noise measurements will be used to enable/disable the equalizer. Set to –127 (0x81) to disable. Default:0x81 (disabled) Property 0x3500 FM_BLEND_RSSI_THRESHOLDS The FM_BLEND_RSSI_THRESHOLDS property sets the RSSI thresholds for maximum and minimum stereo separation (set by Property 0x3501) on the blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x3719 Units: dBµV FM_BLEND_RSSI_THRESHOLDS 15 114 14 13 12 11 10 9 8 7 6 5 4 3 RSSIMAX[7:0] RSSIMIN[7:0] 0x37 0x19 2 1 0 Bit Name Function 15:8 RSSIMAX[7:0] Sets the RSSI Max threshold. If RSSI is above this threshold, maximum stereo separation will be achieved as set by property 0x3501. Default is 55 dBµV. Range is –20 to 120 dBµV. 7:0 RSSIMIN[7:0] Sets the RSSI Min threshold. If RSSI is below this threshold, minimum stereo separation will be achieved as set by property 0x3501. Default is 25 dBµV. Range is –20 to 120 dBµV. Rev. 0.3 AN645 Property 0x3501 FM_BLEND_RSSI_STEREO_SEP The FM_BLEND_RSSI_STEREO_SEP property sets the maximum and minimum stereo separation based on RSSI (set by Property 0x3500) on the blend engine. You can force a constant stereo separation value by setting ST_SEPMAX and ST_SEPMIN to the same value. To disable the stereo blend based on RSSI, set ST_SEPMAX = ST_SEPMIN = 100 (0x64.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x2D00 Units: dB FM_BLEND_RSSI_STEREO_SEP 15 14 13 12 11 10 9 8 7 6 5 4 3 ST_SEPMAX[7:0] ST_SEPMIN[7:0] 0x2D 0x00 2 1 0 Bit Name Function 15:8 ST_SEPMAX[7:0] Sets the maximum stereo separation. Default is 45 dB. Range is 0–64 dB. 7:0 ST_SEPMIN[7:0] Sets the minimum stereo separation. Default is 0 dB. Range is 0–64 dB. Property 0x3502 FM_BLEND_RSSI_ATTACK_TIME The FM_BLEND_RSSI_ATTACK_TIME property sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_BLEND_RSSI_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name 15:0 ATTACK[15:0] Function Sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on RSSI. Default is 16 ms. Range is 1–32767 ms. Rev. 0.3 115 AN645 Property 0x3503 FM_BLEND_RSSI_RELEASE_TIME The FM_BLEND_RSSI_RELEASE_TIME property sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms FM_BLEND_RSSI_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on RSSI. Default is 4000 ms. Range is 1–32767 ms. Property 0x3508 FM_BLEND_MULTIPATH_THRESHOLDS The FM_BLEND_MULTIPATH_THRESHOLDS property sets the Multipath thresholds for maximum and minimum stereo separation (set by Property 0x3509) on the blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x1E3C FM_BLEND_MULTIPATH_THRESHOLDS 15 116 14 13 12 11 10 9 8 7 6 5 4 3 MULTMIN[7:0] MULTMAX[7:0] 0x1E 0x3C 2 1 0 Bit Name Function 15:8 MULTMIN[7:0] Sets the Multipath Min threshold. If Multipath is below this threshold, maximum stereo separation will be achieved as set by property 0x3509. Default is 30. Range is 0–127. 7:0 MULTMAX[7:0] Sets the Multipath Max threshold. If Multipath is above this threshold, minimum stereo separation will be achieved as set by property 0x3509. Default is 60. Range is 0–127. Rev. 0.3 AN645 Property 0x3509 FM_BLEND_MULTIPATH_STEREO_SEP The FM_BLEND_MULTIPATH_STEREO_SEP property sets the maximum and minimum stereo separation based on Multipath (set by Property 0x3508) on the blend engine. You can force a constant stereo separation value by setting ST_SEPMAX and ST_SEPMIN to the same value. To disable the stereo blend based on Multipath, set ST_SEPMAX = ST_SEPMIN = 100 (0x64.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x2D00 Units: dB FM_BLEND_MULTIPATH_STEREO_SEP 15 14 13 12 11 10 9 8 7 6 5 4 3 ST_SEPMAX[7:0] ST_SEPMIN[7:0] 0x2D 0x00 2 1 0 Bit Name Function 15:8 ST_SEPMAX[7:0] Sets the maximum stereo separation. Default is 45 dB. Range is 0–64 dB. 7:0 ST_SEPMIN[7:0] Sets the minimum stereo separation. Default is 0 dB. Range is 0–64 dB. Property 0x350A FM_BLEND_MULTIPATH_ATTACK_TIME The FM_BLEND_MULTIPATH_ATTACK_TIME property sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on Multipath. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_BLEND_MULTIPATH_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name 15:0 ATTACK[15:0] Function Sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on Multipath. Default is 16 ms. Range is 1–32767 ms. Rev. 0.3 117 AN645 Property 0x350B FM_BLEND_MULTIPATH_RELEASE_TIME The FM_BLEND_MULTIPATH_RELEASE_TIME property sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms FM_BLEND_MULTIPATH_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on Multipath. Default is 4000 ms. Range is 1–32767 ms. Property 0x3510 FM_BLEND_USN_THRESHOLDS The FM_BLEND_USN_THRESHOLDS property sets the USN thresholds for maximum and minimum stereo separation (set by Property 0x3511) on the blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x341B Units: –dBFS FM_BLEND_USN_THRESHOLDS 15 14 12 11 10 9 8 7 6 5 4 3 USNMIN[7:0] USNMAX[7:0] 0x34 0x1B 2 1 0 Bit Name Function 15:8 USNMIN[7:0] Sets the USN Min threshold. If USN is below this threshold, maximum stereo separation will be achieved as set by property 0x3511. Default is –52 dBFS. Range is 0–127 –dBFS. USNMAX[7:0] Sets the USN Max threshold. If USN is above this threshold, minimum stereo separation will be achieved as set by property 0x3511. Default is –27 dBFS. Range is 0–127 –dBFS. 7:0 118 13 Rev. 0.3 AN645 Property 0x3511 FM_BLEND_USN_STEREO_SEP The FM_BLEND_USN_STEREO_SEP property sets the maximum and minimum stereo separation based on USN (set by Property 0x3510) on the blend engine. You can force a constant stereo separation value by setting ST_SEPMAX and ST_SEPMIN to the same value. To disable the stereo blend based on USN, set ST_SEPMAX = ST_SEPMIN = 100 (0x64.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x2D00 Units: dB FM_BLEND_USN_STEREO_SEP 15 14 13 12 11 10 9 8 7 6 5 4 3 ST_SEPMAX[7:0] ST_SEPMIN[7:0] 0x2D 0x00 2 1 0 Bit Name Function 15:8 ST_SEPMAX[7:0] Sets the maximum stereo separation. Default is 45 dB. Range is 0–100 dB. 7:0 ST_SEPMIN[7:0] Sets the minimum stereo separation. Default is 0 dB. Range is 0–100 dB. Property 0x3512 FM_BLEND_USN_ATTACK_TIME The FM_BLEND_USN_ATTACK_TIME property sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_BLEND_USN_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name 15:0 ATTACK[15:0] Function Sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on USN. Default is 16 ms. Range is 1–32767 ms. Rev. 0.3 119 AN645 Property 0x3513 FM_BLEND_USN_RELEASE_TIME The FM_BLEND_USN_RELEASE_TIME property sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms FM_BLEND_USN_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on USN. Default is 4000 ms. Range is 1–32767 ms. Property 0x3600 FM_HICUT_RSSI_THRESHOLDS The FM_Hi-cut_RSSI_THRESHOLDS property sets the RSSI thresholds for Hi-cut to begin band limiting and reach maximum band limiting on L+R channel based on max and min cutoff frequency (set by Property 0x3601) on the Hi-cut engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x230F Units: dBµV FM_HICUT_RSSI_THRESHOLDS 15 120 14 13 12 11 10 9 8 7 6 5 4 3 RSSIMAX[7:0] RSSIMIN[7:0] 0x23 0x0F 2 1 0 Bit Name Function 15:8 RSSIMAX[7:0] Sets the RSSI level at which Hi-cut begins to band limit on the L+R channel based on cutoff frequency set by property 0x3601. Default is 35 dBµV. Range is –20–120 dBµV. 7:0 RSSIMIN[7:0] Sets the RSSI level at which Hi-cut reaches maximum band limiting on the L+R channel based on cutoff frequency set by property 0x3601. Default is 15 dBµV. Range is –20–120 dBµV. Rev. 0.3 AN645 Property 0x3601 FM_HICUT_RSSI_CUTOFF_FREQ The FM_Hi-cut_RSSI_CUTOFF_FREQ property sets the maximum and minimum cutoff frequencies based on RSSI (set by Property 0x3600) on the Hi-cut engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-cut based on RSSI, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB428 Units: 100 Hz FM_HICUT_RSSI_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x28 2 1 0 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo separation. Default is 4 kHz. Range is 0–18 kHz. Property 0x3602 FM_HICUT_RSSI_ATTACK_TIME The FM_HI-CUT_RSSI_ATTACK_TIME property sets the transition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_HICUT_RSSI_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name 15:0 ATTACK[15:0] Function Sets the transition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on RSSI. Default is 16 ms. Range is 1–32767 ms. Rev. 0.3 121 AN645 Property 0x3603 FM_HICUT_RSSI_RELEASE_TIME The FM_HICUT_RSSI_RELEASE_TIME property sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms FM_HICUT_RSSI_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on RSSI. Default is 4000 ms. Range is 1–32767 ms. Property 0x3608 FM_HICUT_MULTIPATH_THRESHOLDS The FM_HICUT_MULTIPATH_THRESHOLDS property sets the Multipath thresholds for Hi-cut to begin band limiting and reach maximum band limiting on L+R channel based on max and min cutoff frequencies (set by Property 0x3609) on the Hi-cut engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x3250 FM_HICUT_MULTIPATH_THRESHOLDS 15 14 Bit 122 13 12 11 10 9 8 7 6 5 4 3 MULTMIN[7:0] MULTMAX[7:0] 0x32 0x50 Name 2 1 0 Function 15:8 MULTMIN[7:0] Sets the Multipath level at which Hi-cut reaches max band limiting on the L+R channel based on cutoff frequency set by property 0x3609. Default is 40. Range is 0–127%. 7:0 MULTMAX[7:0] Sets the Multipath level at which Hi-cut begins to band limit on the L+R channel based on cutoff frequency set by property 0x3609. Default is 80. Range is 0–127%. Rev. 0.3 AN645 Property 0x3609 FM_HICUT_MULTIPATH_CUTOFF_FREQ The FM_HICUT_MULTIPATH_CUTOFF_FREQ property sets the maximum and minimum cutoff frequency based on Multipath (set by Property 0x3608) on the Hi-cut engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-cut based on Multipath, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB428 Units: 100 Hz FM_HICUT_MULTIPATH_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x28 2 1 0 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo separation. Default is 4 kHz. Range is 0–18 kHz. Property 0x360A FM_HICUT_MULTIPATH_ATTACK_TIME The FM_HICUT_MULTIPATH_ATTACK_TIME property sets the transition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on Multipath. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_HICUT_MULTIPATH_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-cut mitigation engine decreases the cutoff frequency based on Multipath. Default is 16 ms. Range is 1–32767 ms. Rev. 0.3 123 AN645 Property 0x360B FM_HICUT_MULTIPATH_RELEASE_TIME The FM_HICUT_MULTIPATH_RELEASE_TIME property sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms FM_HICUT_MULTIPATH_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on Multipath. Default is 4000 ms. Range is 1–32767 ms. Property 0x3610 FM_HICUT_USN_THRESHOLDS The FM_HICUT_USN_THRESHOLDS property sets the USN thresholds for Hi-cut to begin band limiting and reach maximum band limiting on L+R channel based on max and min cutoff frequencies (set by Property 0x3611) on the Hi-cut engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x250F Units: –dBFS FM_HICUT_USN_THRESHOLDS 15 14 12 11 10 9 8 7 6 5 4 3 USNMIN[7:0] USNMAX[7:0] 0x25 0x0F 2 1 0 Bit Name 15:8 USNMIN[7:0] Sets the USN level at which Hi-cut reaches max band limiting on the L+R channel based on cutoff frequency set by property 0x3611. Default is –37 dBFS. Range is 0–127 –dBFS. USNMAX[7:0] Sets the Multipath level at which Hi-cut begins to band limit on the L+R channel based on cutoff frequency set by property 0x3611. Default is –15 dBFS. Range is 0–127 –dBFS. 7:0 124 13 Function Rev. 0.3 AN645 Property 0x3611 FM_HICUT_USN_CUTOFF_FREQ The FM_HICUT_USN_CUTOFF_FREQ property sets the maximum and minimum cutoff frequency based on USN (set by Property 0x3610) on the Hi-cut engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-cut based on USN, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB428 Units: 100 Hz FM_HICUT_USN_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x28 2 1 0 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo separation. Default is 4 kHz. Range is 0–18 kHz. Property 0x3612 FM_HICUT_USN_ATTACK_TIME The FM_HICUT_USN_ATTACK_TIME property sets the transition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_HICUT_USN_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name 15:0 ATTACK[15:0] Function Sets the transition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on USN. Default is 16 ms. Range is 1–32767 ms. Rev. 0.3 125 AN645 Property 0x3613 FM_HICUT_USN_RELEASE_TIME The FM_HICUT_USN_RELEASE_TIME property sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms FM_HICUT_USN_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on USN. Default is 4000 ms. Range is 1–32767 ms. Property 0x3700 FM_HIBLEND_RSSI_THRESHOLDS The FM_HIBLEND_RSSI_THRESHOLDS property sets the RSSI thresholds for Hi-blend to begin band limiting and reach maximum band limiting on L-R channel based on max and min cutoff frequency (set by Property 0x3701) on the Hi-blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x371B Units: dBµV FM_HIBLEND_RSSI_THRESHOLDS 15 14 12 11 10 9 8 7 6 5 4 3 RSSIMAX[7:0] RSSIMIN[7:0] 0x37 0x1B 2 1 0 Bit Name Function 15:8 RSSIMAX[7:0] Sets the RSSI level at which Hi-blend begins to band limit on the L-R channel based on cutoff frequency set by property 0x3701. Default is 55 dBµV. Range is –20 to 120 dBµV. RSSIMIN[7:0] Sets the RSSI level at which Hi-blend reaches maximum band limiting on the L-R channel based on cutoff frequency set by property 0x3701. Default is 27 dBµV. Range is –20 to 120 dBµV. 7:0 126 13 Rev. 0.3 AN645 Property 0x3701 FM_HIBLEND_RSSI_CUTOFF_FREQ The FM_HIBLEND_RSSI_CUTOFF_FREQ property sets the maximum and minimum cutoff frequencies based on RSSI (set by Property 0x3700) on the Hi-blend engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-blend based on RSSI, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB41E Units: 100 Hz FM_HIBLEND_RSSI_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x1E 2 1 0 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo separation. Default is 3 kHz. Range is 0–18 kHz. Property 0x3702 FM_HIBLEND_RSSI_ATTACK_TIME The FM_HIBLEND_RSSI_ATTACK_TIME property sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms FM_HIBLEND_RSSI_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0004 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on RSSI. Default is 4 ms. Range is 1–32767 ms. Rev. 0.3 127 AN645 Property 0x3703 FM_HIBLEND_RSSI_RELEASE_TIME The FM_HIBLEND_RSSI_RELEASE_TIME property sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8000 Units: ms FM_HIBLEND_RSSI_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x1F40 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on RSSI. Default is 8000 ms. Range is 1–32767 ms. Property 0x3708 FM_HIBLEND_MULTIPATH_THRESHOLDS The FM_HIBLEND_MULTIPATH_THRESHOLDS property sets the Multipath thresholds for Hi-blend to begin band limiting and reach maximum band limiting on L-R channel based on max and min cutoff frequencies (set by Property 0x3709) on the Hi-blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x193C FM_HIBLEND_MULTIPATH_THRESHOLDS 15 14 Bit 128 13 12 11 10 9 8 7 6 5 4 3 MULTMIN[7:0] MULTMAX[7:0] 0x19 0x3C 2 1 0 Name Function 15:8 MULTMIN[7:0] Sets the Multipath level at which Hi-cut reaches max band limiting on the LR channel based on cutoff frequency set by property 0x3709. Default is 25. Range is 0–127%. 7:0 MULTMAX[7:0] Sets the Multipath level at which Hi-blend begins to band limit on the L-R channel based on cutoff frequency set by property 0x3709. Default is 60. Range is 0–127%. Rev. 0.3 AN645 Property 0x3709 FM_HIBLEND_MULTIPATH_CUTOFF_FREQ The FM_HIBLEND_MULTIPATH_CUTOFF_FREQ property sets the maximum and minimum cutoff frequency based on Multipath (set by Property 0x3708) on the Hi-blend engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-blend based on Multipath, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB41E Units: 100 Hz FM_HIBLEND_MULTIPATH_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x1E 2 1 0 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo separation. Default is 3 kHz. Range is 0–18 kHz. Property 0x370A FM_HIBLEND_MULTIPATH_ATTACK_TIME The FM_HIBLEND_MULTIPATH_ATTACK_TIME property sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on Multipath. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms FM_HIBLEND_MULTIPATH_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0004 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-blend mitigation engine decreases the cutoff frequency based on Multipath. Default is 4 ms. Range is 1–32767 ms. Rev. 0.3 129 AN645 Property 0x370B FM_HIBLEND_MULTIPATH_RELEASE_TIME The FM_HIBLEND_MULTIPATH_RELEASE_TIME property sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8000 Units: ms FM_HIBLEND_MULTIPATH_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x1F40 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on Multipath. Default is 8000 ms. Range is 1–32767 ms. Property 0x3710 FM_HIBLEND_USN_THRESHOLDS The FM_HIBLEND_USN_THRESHOLDS property sets the USN thresholds for Hi-blend to begin band limiting and reach maximum band limiting on L-R channel based on max and min cutoff frequencies (set by Property 0x3711) on the Hi-blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x371E Units: –dBFS FM_HIBLEND_USN_THRESHOLDS 15 14 12 11 10 9 8 7 6 5 4 3 USNMIN[7:0] USNMAX[7:0] 0x37 0x1E 2 1 0 Bit Name Function 15:8 USNMIN[7:0] Sets the USN level at which Hi-blend reaches max band limiting on the L-R channel based on cutoff frequency set by property 0x3711. Default is –55 dBFS. Range is 0–127 –dBFS. USNMAX[7:0] Sets the Multipath level at which Hi-blend begins to band limit on the L-R channel based on cutoff frequency set by property 0x3711. Default is –30 dBFS. Range is 0–127 –dBFS. 7:0 130 13 Rev. 0.3 AN645 Property 0x3711 FM_HIBLEND_USN_CUTOFF_FREQ The FM_HIBLEND_USN_CUTOFF_FREQ property sets the maximum and minimum cutoff frequency based on USN (set by Property 0x3710) on the Hi-blend engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-blend based on USN, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB41E Units: 100 Hz FM_HIBLEND_USN_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x1E 2 1 0 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo separation. Default is 3 kHz. Range is 0–18 kHz. Property 0x3712 FM_HIBLEND_USN_ATTACK_TIME The FM_HIBLEND_USN_ATTACK_TIME property sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms FM_HIBLEND_USN_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0004 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on USN. Default is 4 ms. Range is 1–32767 ms. Rev. 0.3 131 AN645 Property 0x3713 FM_HIBLEND_USN_RELEASE_TIME The FM_HIBLEND_USN_RELEASE_TIME property sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8000 Units: ms FM_HIBLEND_USN_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x1F40 132 Bit Name 15:0 RELEASE[15:0] Function Sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on USN. Default is 8000 ms. Range is 1–32767 ms. Rev. 0.3 AN645 Property 0x4000 FM_RDS_INTERRUPT_SOURCE The FM_RDS_INTERRUPT_SOURCE property configures interrupt related to RDS. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. FM_RDS_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 5 0x000 4 RDSTPPTY RDSPI 0x000 Bit Name 15:5 Reserved 3 0 0 2 1 0 0 RDSSYNC RDSRECV 0 0 0 Function Always write 0. RDSTPPTY If set, generates RDS Interrupt when first valid Block B data has been received or if Block B data is different from last valid Block B data. 0 = Disabled. 1 = Enabled. 3 RDSPI If set, generates RDS Interrupt when first valid Block A data has been received or if Block A data is different from last valid Block A data. 0 = Disabled. 1 = Enabled. 2 Reserved 4 1 0 Always write 0. RDSSYNC If set, generates RDS interrupt when RDS Synchronization status changes. Default is 0. 0 = Disabled. 1 = Enabled. RDSRECV If set, generate an interrupt whenever the RDS FIFO has at least FM_RDS_INTERRUPT_FIFO_COUNT entries. Default is 0 0 = Disabled. 1 = Enabled. Rev. 0.3 133 AN645 Property 0x4001 FM_RDS_INTERRUPT_FIFO_COUNT The FM_RDS_INTERRUPT_FIFO_COUNT property sets the minimum number of RDS groups stored in the RDS FIFO before RDSRECV is set. RDSRECV is disabled if set to 0. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 FM_RDS_INTERRUPT_FIFO_COUNT 15 134 14 13 12 11 10 9 8 7 6 5 4 3 0x00 DEPTH[7:0] 0x00 0x00 Bit Name 15:8 Reserved 7:0 DEPTH[7:0] 2 1 Function Always write 0. Sets the minimum number of RDS Groups stored in the RDS FIFO required before RDSRECV is set. RDSRECV is disabled if set to 0. Default is 0. Range is 0–25 Rev. 0.3 0 AN645 Property 0x4002 FM_RDS_CONFIG The FM_RDS_CONFIG property configures RDS settings to enable RDS processing (RDSEN) and set RDS block error thresholds. When a RDS Group is received, all block errors must be less than or equal to the associated block error threshold for the group to be stored in the RDS FIFO. If blocks with errors are permitted into the FIFO, the block error information can be reviewed when the group is read using the FM_RDS_STATUS command. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 FM_RDS_CONFIG 15 14 13 12 11 10 9 8 0x00 Name 15:8 Reserved 7:6 BLETHB[1:0] 5:4 BLETHCD[1:0] 3:1 Reserved 0 RDSEN 6 5 4 BLETHB[1:0] BLETHCD[1:0] 0x00 Bit 7 0x0 0x0 3 2 1 0 0x0 RDSEN 0x0 0 Function Always write 0. Block Error Threshold BLOCKB. Block B is most critical because it tells what C and D contain. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. Block Error Threshold for BLOCKC and BLOCKD. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. Always write 0. Enables RDS processing. Default is 0. 0 = RDS Disabled. 1 = RDS Enabled. Rev. 0.3 135 AN645 Property 0x4003 FM_RDS_CONFIDENCE The FM_RDS_CONFIDENCE property sets the required receiver confidence level for each RDS block prior to demodulation. A higher confidence requirement will result in more block errors (higher percentage of blocks with BLE=3), but reduces the chance of decoder errors (lower percentage of blocks that contain incorrect information despite having BLE<3). Higher confidence requirements may result in a decrease in the frequency with which RDS data is stored in the FIFO. Higher block error rates will affect RDS sensitivity tests. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 0x1111 FM_RDS_CONFIDENCE 15 14 12 11 10 9 8 7 6 5 4 3 2 1 0 CONFIDENCEA[3:0] CONFIDENCEB[3:0] CONFIDENCEC[3:0] CONFIDENCED[3:0] 0x1 0x1 0x1 0x1 Bit 15:12 11:8 7:4 3:0 136 13 Name Function CONFIDENCEA[3:0] Sets the decoder error rate threshold for BLOCK A. 0 = Reserved. 1 = Lowest confidence required. A valid and usable confidence threshold. 2–14 = Medium confidence required. High value may result in all blocks being marked as uncorrectable. 15 = Highest confidence required. This setting may result in all blocks being marked as uncorrectable. CONFIDENCEB[3:0] Sets the decoder error rate threshold for BLOCK B. 0 = Reserved. 1 = Lowest confidence required. A valid and usable confidence threshold. 2–14 = Medium confidence required. High value may result in all blocks being marked as uncorrectable. 15 = Highest confidence required. This setting may result in all blocks being marked as uncorrectable. CONFIDENCEC[3:0] Sets the decoder error rate threshold for BLOCK C. 0 = Reserved. 1 = Lowest confidence required. A valid and usable confidence threshold. 2–14 = Medium confidence required. High value may result in all blocks being marked as uncorrectable. 15 = Highest confidence required. This setting may result in all blocks being marked as uncorrectable. CONFIDENCED[3:0] Sets the decoder error rate threshold for BLOCK D. 0 = Reserved. 1 = Lowest confidence required. A valid and usable confidence threshold. 2–14 = Medium confidence required. High value may result in all blocks being marked as uncorrectable. 15 = Highest confidence required. This setting may result in all blocks being marked as uncorrectable. Rev. 0.3 AN645 9.3. Commands and Properties for AM Receiver Table 16. AM Receiver Command Summary Number Name Summary 0x40 AM_TUNE_FREQ Tunes the AM receiver to a frequency in 1 kHz steps. 0x41 AM_SEEK_START Initiates a seek for a channel that meets the validation criteria for AM. 0x42 AM_RSQ_STATUS Returns status information about the received signal quality. 0x45 AM_ACF_STATUS Returns status information about automatically controlled features. 0x47 AM_AGC_STATUS Reports the status of AM AGC. Table 17. AM Receiver Property Summary Number Name Default 0x0400 AM_SOFT_MUTE_MAX_ATTENUATION Summary 0x000C Sets the maximum soft mute attenuation. 12 0x0008 0x0401 AM_SOFT_MUTE_TRIGGER_THRESHOLD Sets the SNR threshold for soft mute to start. 8 0x0402 AM_SOFT_MUTE_END_THRESHOLD 0x0000 Sets the SNR threshold where soft mute will stop attenuating. 0 0x0403 AM_SOFT_MUTE_RELEASE_TIME 0x01F4 Sets the maximum soft mute release time in ms. 500 0x0404 AM_SOFT_MUTE_ATTACK_TIME 0x0500 AVC_MIN_GAIN 0xF800 Sets the minimum gain for automatic volume –2048 control. 0x0501 AVC_MAX_GAIN 0x27EC Sets the maximum gain for automatic volume 10220 control. 0x0700 AM_FE_AGC_CONFIG 0xF018 Specifies the input path for the RF signal and 61464 other front-end configuration options. 0x0708 AM_IF_AGC_ATTACK_MS 0x0050 Sets the number of milliseconds the IF high peak detector must be exceeded before atten80 uating the appropriate block. 0x0709 AM_IF_AGC_RELEASE_MS 0x0078 Sets the maximum soft mute attack time in ms. 120 0x342 804 Rev. 0.3 Sets the number of milliseconds the IF low peak detector must not be exceeded before increasing the gain of the appropriate block 137 AN645 Table 17. AM Receiver Property Summary (Continued) Number 0x070C Name AM_RF_AGC_ATTACK_MS Default Summary 0x0008 Sets the number of milliseconds the wideband RF high-peak detector must be exceeded before attenuating the appropriate 8 block. 0x0320 Sets the number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the 800 appropriate block. 0x070D AM_RF_AGC_RELEASE_MS 0x070E AM_LNA_PD_THRESHOLD 0x5104 Sets the high threshold and hysteresis for the 20740 LNA peak detector. 0x1100 AM_SEEK_BAND_BOTTOM 0x0208 Sets the lower seek boundary of the AM band in multiples of 1 kHz. 520 0x1101 AM_SEEK_BAND_TOP 0x1102 AM_SEEK_FREQUENCY_SPACING 0x000A Sets the frequency spacing for the AM band in multiples of 1 kHz when performing a seek. 10 0x1200 AM_RSQ_INTERRUPT_SOURCE 0x0000 Configures interrupt related to Received Signal Quality metrics (AM_RSQ_STATUS). 0 0x1201 AM_RSQ_SNR_HIGH_THRESHOLD 0x007F Sets high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. 127 0x1202 AM_RSQ_SNR_LOW_THRESHOLD 0xFF80 Sets low threshold, which triggers the RSQ –128 interrupt if the SNR is below this threshold. 0x1203 AM_RSQ_RSSI_HIGH_THRESHOLD 0x007F Sets high threshold, which triggers the RSQ interrupt if the RSSI is above this threshold. 127 0x1204 AM_RSQ_RSSI_LOW_THRESHOLD 0xFF80 Sets low threshold, which triggers the RSQ –128 interrupt if the RSSI is below this threshold. 0x1300 AM_ACF_INTERRUPT_SOURCE 0x06AE Sets the upper seek boundary for the AM 1710 band in multiples of 1 kHz. 0x0000 Enables the ACF interrupt sources. 0 0x001F 0x1301 AM_ACF_SM_THRESHOLD Sets the softmute interrupt threshold in dB. 31 138 Rev. 0.3 AN645 Table 17. AM Receiver Property Summary (Continued) Number Name Default Summary 0x1302 AM_ACF_CHBW_THRESHOLD 0x0000 Sets the Channel Filter Bandwidth interrupt threshold in units of 100 Hz. 0 0x1303 AM_ACF_HICUT _THRESHOLD 0x0000 Sets the Hi-cut interrupt threshold in units of 100 Hz. 0 0x1306 AM_ACF_CONTROL_SOURCE 0x0000 Determines if SNR or RSSI will be used as the controlling metric for ACF features. 0 0x2000 AM_VALID_MAX_TUNE_ERROR 0x2003 AM_VALID_SNR_THRESHOLD 0x0005 Sets the SNR threshold for a valid AM Seek/ Tune. 5 0x2004 AM_VALID_RSSI_THRESHOLD 0x000A Sets the RSSI threshold for a valid AM Seek/ Tune. 10 0x2200 AM_CHBW_SQ_MIN_MAX 0x2314 Sets the maximum and minimum channel BW as determined by SNR/RSSI in units of 8980 100 Hz. 0x2201 AM_CHBW_SQ_HIGH_THRESHOLD 0x001E Sets the SNR/RSSI threshold for maximum channel filter bandwidth. 30 0x2202 AM_CHBW_SQ_LOW_THRESHOLD 0x000F Sets the SNR/RSSI threshold for minimum channel filter bandwidth. 15 0x2203 AM_CHBW_SQ_WIDENING_TIME 0x0800 Sets the channel filter bandwidth widening 2048 time based on SNR/RSSI in units of ms. 0x2204 AM_CHBW_SQ_NARROWING_TIME 0x0010 Sets the channel filter bandwidth narrowing time based on SNR/RSSI in units of ms. 16 0x2205 AM_CHBW_ASSI_MIN_MAX 0x3232 Sets the maximum and minimum channel BW 12850 as determined by ASSI in units of 100 Hz. 0x2206 AM_CHBW_ASSI_LOW_THRESHOLD 0x000A Sets the ASSI threshold for maximum channel filter bandwidth. 10 0x2207 AM_CHBW_ASSI_HIGH_THRESHOLD 0x001E Sets the ASSI threshold for minimum channel filter bandwidth. 30 0x004B Sets the maximum frequency error allowed before setting the AFCRL indicator. 75 Rev. 0.3 139 AN645 Table 17. AM Receiver Property Summary (Continued) Number Name Default Summary 0x2208 AM_CHBW_ASSI_WIDENING_TIME 0x0010 Sets the channel filter bandwidth widening time based on ASSI in units of ms. 16 0x2209 AM_CHBW_ASSI_NARROWING_TIME 0x0010 Sets the channel filter bandwidth narrowing time based on ASSI in units of ms. 16 0x3100 AM_HICUT_SQ_HIGH_THRESHOLD 0x0008 Sets the SNR/RSSI based Hi-cut high SNR/ RSSI threshold. 8 0x3101 AM_HICUT_SQ_LOW_THRESHOLD 0x0000 Sets the SNR/RSSI based Hi-cut low SNR/ RSSI threshold. 0 0x3102 AM_HICUT_ATTACK_TIME 0x0010 Sets the Hi-cut cutoff frequency attack time in ms. 16 0x3103 AM_HICUT_RELEASE_TIME 0x07D0 Sets the Hi-cut cutoff frequency release time 2000 in ms. 0x3104 AM_HICUT_CUTOFF_FREQ 0x280A Sets the Hi-cut Cutoff Max and Min audio fre10250 quencies. 0x3105 AM_LOWCUT_MIN_FREQ 0x0000 Sets the minimum LowCut cutoff frequency. 0 0x0000 0x3106 AM_LOWCUT_MAX_FREQ Sets the maximum LowCut cutoff frequency. 0 0x0000 Control property for IBOC Blend (Si4777 only). 0 0x3300 AM_IBOC_CONTROL 0x3301 AM_IBOC_ANALOG_TO_HD_ CROSSFADE_TIME 0x03E8 Sets the crossfade time between full analog and full HD Digital audio in ms 1000 (Si4777 only). 0x3302 AM_IBOC_HD_TO_ANALOG_ CROSSFADE_TIME 0x03E8 Sets the crossfade time from full HD Digital to 1000 full analog audio in ms (Si4777 only). 0x3303 AM_IBOC_DYNAMIC_GAIN 0x007F Sets the digital audio dynamic linear scaling factor (Si4777 only). 127 0x3304 AM_IBOC_STATIC_GAIN 0x0100 Sets the digital audio static linear gain factor (Si4777 only). 256 140 Rev. 0.3 AN645 9.3.1. AM Receiver Commands Command 0x40 AM_TUNE_FREQ The AM_TUNE_FREQ command sets the AM Receiver to tune to a frequency in 1 kHz units. The CTS bit (and optional interrupt) is set when it is safe to send the next command. The ERR bit (and optional interrupt) is set if an invalid argument is sent. Note that only a single interrupt occurs if both the CTS and ERR bits are set. The optional STC interrupt is set when the command completes. This command may only be sent in powerup mode. The command clears the STC bit if it is already set. Command Bit 7 6 5 4 3 CMD ARG1 2 1 0 0x40 0 0 ZIFSR ARG2 FREQH[7:0] ARG3 FREQL[7:0] ARG4 ANTCAPH[7:0] ARG5 ANTCAPL[7:0] Rev. 0.3 141 AN645 ARG Bit Name 1 7 Reserved 1 6 ZIFSR 1 5:0 Reserved 2 7:0 3 7:0 4 7:0 5 7:0 Function Always write 0. Sets the ZIP sample rate. ZIFSR=0, low ZIF sample rate (40.625, 42.1875, or 46.5117 kHz, depending on crystal frequency) ZIFSR=1, high ZIF sample rate (650, 675, or 744.1875 kHz, depending on crystal frequency) See section “7. Digital ZIF I/Q Interface”. Always write 0. FREQH[7:0] Tune Frequency High Byte. This byte in combination with FREQL selects the tune frequency in units of 1 kHz. Valid range is from 520 to 1710 (520–1710 kHz). FREQL[7:0] Tune Frequency Low Byte. This byte in combination with FREQH selects the tune frequency in units of 1 kHz. Valid range is from 520 to 1710 (520–1710 kHz). ANTCAPH[7:0] Antenna Tuning Capacitor High Byte. This byte, in combination with ANTCAPL[7:0], sets the antenna tuning capacitor value in 92 fF increments. Max value is 580 pF. Range is 1-6304. Setting ANTCAP to 0 automatically determines the capacitor value. ANTCAPL[7:0] Antenna Tuning Capacitor Low Byte. This byte, in combination with ANTCAPH[7:0], sets the antenna tuning capacitor value in 92 fF increments. Max value is 580 pF. Range is 1-6304. Setting ANTCAP to 0 automatically determines the capacitor value. Response Bit 7 6 STATUS CTS ERR 142 5 4 XX Rev. 0.3 3 2 1 0 RSQINT X ACFINT STCINT AN645 Command 0x41 AM_SEEK_START The AM_SEEK_START command begins searching for a valid frequency. In order for a station to be considered valid, each of the following thresholds must be met: AM_VALID_SNR_THRESHOLD, AM_VALID_RSSI_THRESHOLD, and AM_VALID_MAX_TUNE_ERROR. Clears any pending STCINT or RSQINT interrupt status. Seek can be cancelled through setting the CANCEL bit in the AM_RSQ_STATUS command. The CTS bit (and optional interrupt) is set when it is safe to send the next command. RSQINT status is only cleared by the AM_RSQ_STATUS command when the RSQACK bit is set. The ERR bit (and optional interrupt) is set if an invalid argument is sent. Note that only a single interrupt occurs if both the CTS and ERR bits are set. The optional STC interrupt is set when the command completes. This command may only be sent in powerup mode. The command clears the STCINT bit if it is already set. Command Bit 7 6 5 4 3 2 SEEKUP WRAP 1 0 0x41 CMD 0000 ARG1 ARG Bit Name 1 7:4 Reserved 00 Function Always write 0. Wrap/Halt. Determines whether the seek should Wrap = 1, or Halt = 0 when it hits the band limit. 1 3 WRAP 1 2 SEEKUP Seek Up/Down. Determines the direction of the search, either UP = 1, or DOWN = 0. 1 1:0 Reserved Always write 0. Response Bit 7 6 STATUS CTS ERR 5 4 XX Rev. 0.3 3 2 1 0 RSQINT X ACFINT STCINT 143 AN645 Command 0x42 AM_RSQ_STATUS The AM_RSQ_STATUS command returns status information about the received signal quality. This command returns Received Signal Strength Indicator (RSSI), Signal to Noise Ratio (SNR), High Side Adjacent Channel Strength (HASSI), Low Side Adjacent Channel Strength (LASSI), Frequency Offset (FREQOFF), and AM Modulation Index (MOD) associated with the desired channel. It also indicates valid channel (VALID) and AFC rail status (AFCRL). This command can be used to check if the received signal is above the RSSI high threshold as reported by RSSIHINT, or below the RSSI low threshold as reported by RSSILINT. It can also be used to check if the signal is above the SNR high threshold as reported by SNRHINT, or below the SNR low threshold as reported by SNRLINT. The command clears the RSQINT, SNRHINT, SNRLINT, RSSIHINT and RSSILINT interrupt bits when RSQACK bit of ARG1 is set. If the condition is still true after the interrupt is cleared another interrupt will fire assuming that bit is enabled in AM_RSQ_INTERRUPT_SOURCE. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Bit 7 6 5 4 2 1 0 RSQACK ATTUNE CANCEL STCACK 0x42 CMD 0000 ARG1 ARG Bit Name 1 7:4 Reserved Always write 0. 1 3 RSQACK Clears RSQINT, SNRHINT, SNRLINT, RSSIHINT, RSSILINT if set. ATTUNE Returns the values of metrics as of tune time. When the AT_TUNE bit is set, values returned for RSQ_STATUS are the values calculated at tune and do not change unless another TUNE_FREQ command is called. This feature can be used to determine why seek stopped at the current station. 1 144 3 2 Function 1 1 CANCEL Aborts a seek or tune currently in progress 0 = Don't abort. 1 = Abort. 1 0 STCACK Clears the STC interrupt status indicator if set. Rev. 0.3 AN645 Response Bit 7 6 5 STATUS CTS ERR RESP1 X X X RESP 2 BLTF X SNRREADY 4 3 2 1 0 RSQINT X ACFINT STCINT X SNRHINT SNRLINT RSSIHINT RSSILINT RSSIREA DY X X AFCRL VALID XX RESP 3 READFREQ[15:8] RESP 4 READFREQ[7:0] RESP 5 FREQOFF[7:0] RESP 6 RSSI[7:0] RESP 7 SNR[7:0] RESP 8 XXXXXXXX RESP 9 LASSI[7:0] RESP 10 HASSI[7:0] RESP 11 XXXXXXXX RESP 12 MOD[7:0] RESP 13 ANTCAPH[7:0] RESP 14 ANTCAPL[7:0] Rev. 0.3 145 AN645 RESP Bit Name 1 7:4 Reserved Values may vary. 1 3 SNRHINT SNR Detect High 0 = Received SNR has not exceeded above SNR programmed using AM_RSQ_SNR_HIGH_THRESHOLD. 1 = Received SNR has exceeded above SNR threshold programmed using AM_RSQ_SNR_HIGH_THRESHOLD. SNRLINT SNR Detect Low 0 = Received SNR has not fallen below SNR threshold programmed using AM_RSQ_SNR_LOW_THRESHOLD. 1 = Received SNR has fallen below SNR threshold programmed using AM_RSQ_SNR_LOW_THRESHOLD. RSSIHINT RSSI Detect High 0 = RSSI has not exceeded above RSSI threshold programmed using AM_RSQ_RSSI_HIGH_THRESHOLD. 1 = RSSI has exceeded above RSSI threshold programmed using AM_RSQ_RSSI_HIGH_THRESHOLD. RSSILINT RSSI Detect Low 0 = RSSI has not fallen below RSSI threshold. programmed using AM_RSQ_RSSI_LOW_THRESHOLD. 1 = RSSI has fallen below RSSI threshold programmed using AM_RSQ_RSSI_LOW_THRESHOLD. Band Limit Reports if a seek hit the band limit (WRAP = 0 in AM_SEEK_START) or wrapped to the original frequency (WRAP = 1). 1 1 1 146 2 1 0 2 7 BLTF 2 6 Reserved Function Values may vary. Rev. 0.3 AN645 RESP 2 Bit 5 Name Function SNRREADY SNR Status When set, indicates that the SNR metric was read as part of a tune. If this flag is not set once tune completes, the SNR metric was not measured. A metric not measured indicates that a tune was terminated prematurely due to an invalidating condition (i.e., RSSI did not meet the minimum threshold).In this case, tune time RSQ will report 0 for SNR. The normal running SNR is not affected by this flag. 0 = SNR measurement in progress (tune in progress). 1 = SNR measurement ready or not taken (tune completed). RSSI Status When set, indicates that the RSSI metric was read as part of a tune. If this flag is not set once tune completes, the RSSI metric was not measured. A metric not measured indicates that a tune was terminated prematurely due to an invalidating condition (i.e., RSSI did not meet the minimum threshold).In this case, tune time RSQ will report 0 for RSSI. The normal running RSSI is not affected by this flag. 0 = RSSI measurement in progress (tune in progress). 1 = RSSI measurement ready or not taken (tune completed). 2 4 RSSIREADY 2 3:2 Reserved 2 1 AFCRL Set if the AFC rails (AFC gets railed if FREQOFF > MAX_TUNE_ERROR). 2 0 VALID Reports if the channel is valid based on the settings of AM_VALID_RSSI_THRESHOLD, AM_VALID_SNR_THRESHOLD, AM_VALID_MAX_TUNE_ERROR. 3,4 15:0 READFREQ[15:0] 5 7:0 FREQOFF[7:0] 6 7:0 RSSI[7:0] Received Signal Strength indicator in dBµV (–128 to 127). 7 7:0 SNR[7:0] RF SNR indicator in dB (–128 to 127). 8 7:0 Reserved Values may vary 9 7:0 LASSI[7:0] Low Side Adjacent Channel Strength Indicator reports the Signal + Noise power relative to the carrier. (–128 to 127). 10 7:0 HASSI[7:0] High Side Adjacent Channel Strength Indicator reports the Signal + Noise power relative to the carrier. (–128 to 127). 11 7:0 Reserved Values may vary. 12 7:0 MOD[7:0] AM Modulation Index in percent range 0–100. Values may vary Returns the currently tuned frequency. Frequency offset in units of 2 ppm (–128 to 127). Rev. 0.3 147 AN645 RESP 13 14 148 Bit 7:0 7:0 Name Function ANTCAPH[7:0] Antenna Tuning Capacitor High Byte. This byte, in combination with ANTCAPL[7:0], reports the antenna tuning capacitor value in 92 fF increments. Max value is 580 pF. Range is 1-6304. ANTCAPL[7:0] Antenna Tuning Capacitor High Byte. This byte, in combination with ANTCAPH[7:0], reports the antenna tuning capacitor value in 92 fF increments. Max value is 580 pF. Range is 1-6304. Rev. 0.3 AN645 Command 0x45 AM_ACF_STATUS The AM_ACF_STATUS command returns status information about automatically controlled features. This command returns the Soft Mute Attenuation, Channel Filter Bandwidth, and Hi-cut cutoff frequency associated with the desired channel. If SMUTE bit is high it indicates that is audio is soft muted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Bit 7 6 5 4 3 2 1 0 0x45 CMD 0 ARG1 ACFACK ARG Bit Name Function 1 7:1 Reserved Always write 0. 1 0 ACFACK If set to 1, clears ACFINT and any ACF interrupt bits. Response Bit 7 6 STATUS CTS ERR 4 XX 3 2 1 0 RSQINT X ACFINT STCINT HICUT_INT CHBW_INT SOFTMUTE_INT XXX XXXX RESP1 XXXXXXX RESP2 RESP3 5 XXX SMUTE SMATTN[4:0] RESP4 CHANBW[7:0] RESP5 HICUT [7:0] Rev. 0.3 149 AN645 RESP Bit Name 1 7:3 Reserved 1 2 HICUT_INT Indicates that Hi-cut cutoff frequency has crossed below the Hi-cut threshold set by AM_ACF_HICUT_THRESHOLD. 1 1 CHBW_INT Indicates that channel filter bandwidth is less than the threshold set by ACF_CHBW_THRESHOLD. 1 0 SOFTMUTE_INT 2 7:1 Reserved 2 0 SMUTE 3 7:5 Reserved 3 4:0 SMATTN[4:0] Soft mute attenuation level in dB. Range: 0–31. 4 7:0 CHANBW[7:0] Channel filter bandwidth in 100 Hz. Range: 0–150. 5 7:0 HICUT [7:0] 150 Function Values may vary. Indicates that SM attenuation has increased above ACF_SM_THRESHOLD. Values may vary. 0 = Audio is not soft muted. 1 = Audio is soft muted. Values may vary. Hi-cut cutoff frequency in units of 100 Hz. Range: 10–50. Rev. 0.3 AN645 Command 0x47 AM_AGC_STATUS The AM_AGC_STATUS command reports the current status of the AM AGC. The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command Bit 7 6 5 4 3 2 1 0 3 2 1 0 RSQINT X ACFINT STCINT AMHI AMLO 0x47 CMD Response Bit 7 6 Status CTS ERR 5 4 XX XXXXXX RESP1 RESP 2 XX RESP 3 XX RESP 4 PGAGAIN[7:0] RESP 5 RFATTN[7:0] RESP Bit Name 1 7:2 Reserved 1 1 AMHI 0 = AM LNA PD high threshold is not tripped. 1 = AM LNA PD high threshold is tripped. 1 0 AMLO 0 = AM LNA PD low threshold is not tripped. 1 = AM LNA PD low threshold is tripped. 2 7:0 Reserved Values may vary. 3 7:0 Reserved Values may vary. 4 7:0 5 7:0 Function Values may vary. PGAGAIN[7:0] PGA gain in dB. AM loop resistive attenuation index. Range: 0-63 0 = 800 Kohms ~ no attenuation RFATTN[7:0] 1 = 0.875 * 800 k 2 = 0.875^2 * 800 k 63 = 0.875^63 * 800 k = 177 Rev. 0.3 151 AN645 9.3.2. AM Receiver Properties Property 0x0400 AM_SOFT_MUTE_MAX_ATTENUATION The AM_SOFT_MUTE_MAX_ATTENUATION property sets the maximum attenuation in dB that will be applied by the softmute feature. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 12 Units: dB AM_SOFT_MUTE_MAX_ATTENUATION 15 14 13 12 11 Bit Name 15:5 Reserved 4:0 SMATTN[4:0] 10 9 8 7 6 5 4 3 2 1 0x000 SMATTN[4:0] 0x000 0x0C 0 Function Always write 0. Sets the maximum attenuation in dB that will be applied by the softmute feature. Default is 12 dB. Range is 0–31 dB. Property 0x0401 AM_SOFT_MUTE_TRIGGER_THRESHOLD The AM_SOFT_MUTE_TRIGGER_THRESHOLD property sets the SNR threshold in dB to engage softmute. The CTS bit (and optional interrupt) is set when it is safe to send the next command. If USE_RSSI is set in AM_ACF_CONTROL_SOURCE property, then property 0x0401 refers to RSSI threshold. This property may only be set or read in powerup mode. Default: 8 Units: dB AM_SOFT_MUTE_TRIGGER_THRESHOLD 15 152 14 13 12 11 10 9 8 7 6 5 4 3 0x00 SMTRGTH[7:0] 0x00 0x08 Bit Name 15:8 Reserved 7:0 SMTRGTH[7:0] Function Always write 0. Sets the SNR threshold in dB to engage softmute. Default is 8 dB. Range is –127 to 127 dB. Rev. 0.3 2 1 0 AN645 Property 0x0402 AM_SOFT_MUTE_END_THRESHOLD The AM_SOFT_MUTE_END_THRESHOLD property sets the SNR threshold in dB at which softmute attenuation will be set to its maximum value. When the SNR is at this level or lower, the audio attenuation will be set to AM_SOFT_MUTE_MAX_ATTENUATION. The CTS bit (and optional interrupt) is set when it is safe to send the next command. If USE_RSSI is set in AM_ACF_CONTROL_SOURCE property, then property 0x0402 refers to RSSI threshold. This property may only be set or read in powerup mode. Default: 0 Units: dB AM_SOFT_MUTE_END_THRESHOLD 15 14 13 12 10 9 8 7 6 5 4 3 0x00 SMENDTH[7:0] 0x00 0x00 Bit Name 15:8 Reserved 7:0 11 2 1 0 Function Always write 0. SMENDTH[7:0] Sets the SNR threshold in dB at which softmute attenuation will be set to its maximum value given by AM_SOFT_MUTE_MAX_ATTENUATION property. Default is 0 dB. Range is –127 to 127 dB. Property 0x0403 AM_SOFT_MUTE_RELEASE_TIME The AM_SOFT_MUTE_RELEASE_TIME property sets the maximum time in ms it takes to unmute the audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 500 Units: ms AM_SOFT_MUTE_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x01F4 Bit 15:0 Name RELEASE[15:0] Function Sets the maximum time in ms it takes to unmute the audio. Default is 500 ms. Range is 1–32767 ms. Note that there will be 16 ms of filter delay for the RSSI/SNR metric before softmute can engage/disengage. Rev. 0.3 153 AN645 Property 0x0404 AM_SOFT_MUTE_ATTACK_TIME The AM_SOFT_MUTE_ATTACK_TIME property sets the maximum time in ms it takes to mute the audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 120 Units: ms AM_SOFT_MUTE_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0078 Bit Name Function Sets the maximum time in ms it takes to mute the audio. 15:0 ATTACK[15:0] Default is 120 ms. Range is 1–32767 ms. Note that there will be 16 ms of filter delay for the RSSI/SNR metric before softmute can engage/ disengage. Property 0x0500 AVC_MIN_GAIN The AVC_MIN_GAIN property sets the minimum gain for automatic volume control. The minimum gain value is given by MINGAIN = g * 170 where g is the desired minimum AVC gain in dB. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –2048 AVC_MIN_GAIN 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 MINGAIN[15:0] 0xF800 Bit Name Function 15:0 MINGAIN[15:0] The minimum gain value for the AVC. MINGAIN = g x 170. Range for MINGAIN is –4096 to 3061. This implies that the range of g is –24 dB to +18 dB 154 Rev. 0.3 AN645 Property 0x0501 AVC_MAX_GAIN The AVC_MAX_GAIN property sets the maximum gain for automatic volume control. The maximum gain value is given by MAXGAIN = g x 170 where g is the desired maximum AVC gain in dB. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 10220 AVC_MAX_GAIN 15 14 13 12 11 10 0 9 8 7 6 5 4 3 2 1 0 MAXGAIN[14:0] 0x27EC 0 Bit Name 15 Reserved 14:0 MAXGAIN[14:0] Function Always set to 0. The maximum gain value for the AVC. MAXGAIN = g x 170. Range is 0– 32767. This implies that the range of g is 0–193 dB Property 0x0700 AM_FE_AGC_CONFIG Specifies the input path for the RF signal and other front-end configuration options. The CTS bit (and optional interrupt) is set when it is safe to send the next command. The property may only be set or read when in the powerup mode. Changes to this property take effect after the next tune is completed. Default: 0x14 AM_FE_AGC_CONFIG 15:12 11:8 CCL000 0 0xF000 0 7 6 FMMIX NOINTRU 0 0 5 4 3 2 1 ATTENFM HARMREJ INPUTSELECT[3:0] 0 1 0x8 Bit Name 15:12 CCL 11:8 Reserved Always write 0. 7 Reserved Always write 0. 6 NOINTRU 0=In AM, external FM intrusion filter exists on AM antenna circuit. 1=In AM, FM attenuators are off. 5 ATTENFM 0=In AM, FM attenuators are turned on to improve FM intrusion. 1=In AM, FM attenuators are off. 4 HARMREJ 0=Harmonic reject is disabled. 1=Harmonic reject is enabled. 3:0 INPUTSELECT[3:0] 0 Function Coupling Capacitor value at loop input. Default is 15 pF. 8=Receive signal comes into the AMIL pin (loop antenna) Rev. 0.3 155 AN645 Property 0x0708 AM_IF_AGC_ATTACK_MS Sets the number of milliseconds the IF high peak detector must be exceeded before attenuating the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 80 Units: ms AM_IF_AGC_ATTACK_MS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 IF_AGC_ATTACK_MS[15:0] 0x0050 Bit Name Function 15:0 IF_AGC_ATTACK_MS[15:0] Number of milliseconds the IF high peak detector must be exceeded before attenuating the appropriate block. Range: 4–4096 ms. Property 0x0709 AM_IF_AGC_RELEASE_MS Sets the number of milliseconds the IF low peak detector must not be exceeded before increasing the gain of the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 804 Units: ms AM_IF_AGC_RELEASE_MS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 IF_AGC_RELEASE_MS[15:0] 0x0324 Bit Name 15:0 IF_AGC_RELEASE_MS[15:0] Function Number of milliseconds the IF low peak detector must not be exceeded before increasing the gain of the appropriate block. Range: 4–4096 ms. Note: For best performance AM_IF_AGC_RELEASE_MS > AM_RF_AGC_RELEASE_MS and set AM_IF_AGC_RELEASE_MS to 804 ms for AM_RF_AGC_RELEASE_MS of 800 ms. 156 Rev. 0.3 0 AN645 Property 0x070C AM_RF_AGC_ATTACK_MS The AM_RF_AGC_ATTACK_MS property sets the number of milliseconds the wideband RF high-peak detector must be exceeded before attenuating the appropriate block. The peak detectors are only sampled once every 3– 5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8 Units: ms AM_RF_AGC_ATTACK_MS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RF_AGC_ATTACK_MS[15:0] 0x0008 Bit Name Function 15:0 RF_AGC_ATTACK_MS[7:0] Number of milliseconds the wide-band RF high-peak detector must be exceeded before attenuating the appropriate block. Default is 8 ms. Range is 4–4096 ms. Property 0x070D AM_RF_AGC_RELEASE_MS The AM_RF_AGC_RELEASE_MS property sets the number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 800 Units: ms AM_RF_AGC_RELEASE_MS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RF_AGC_RELEASE_MS[15:0] 0x0320 Bit Name Function 15:0 RF_AGC_RELEASE_MS[7:0] Number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. Default is 800 ms. Range is 4–4096 ms. Note: For best performance, AM_IF_AGC_RELEASE_MS > AM_RF_AGC_RELEASE_MS Rev. 0.3 157 AN645 Property 0x070E AM_LNA_PD_THRESHOLD The AM_LNA_PD_THRESHOLD property sets the high threshold and hysteresis for the LNA peak detector. The high threshold sets the level at which the AGC increases attenuation. The hysteresis is how many dB below the high threshold the level must drop before the AGC decreases attenuation. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x5104 AM_LNA_PD_THRESHOLD 15 14 Bit 15:8 7:0 158 13 12 11 10 9 8 7 6 5 4 3 HIGH[7:0] HYST[7:0] 0x51 0x04 Name 2 1 0 Function HIGH[7:0] Sets the level in dBµV at which AGC increases attenuation. HIGH[7:0] Range: 79–93. 79 = 79 dBµV. 81 = 81 dBµV. 83 = 83 dBµV. 85 = 85 dBµV. 87 = 87 dBµV. 89 = 89 dBµV. 91 = 91 dBµV. 93 = 93 dBµV. HYST[7:0] Sets how many dB below the high threshold the level must drop before the AGC decreases attenuation. HYST[7:0] Range: 3–6. 3 = 3 dB. 4 = 4 dB. 5 = 5 dB. 6 = 6 dB. Rev. 0.3 AN645 Property 0x1100 AM_SEEK_BAND_BOTTOM The AM_SEEK_BAND_BOTTOM property sets the bottom of the AM band for seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 520 kHz. Default: 520 Units: kHz AM_SEEK_BAND_BOTTOM 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 AMSKFREQL[15:0] 0x0208 Bit Name 15:0 Function AMSKFREQL[15:0] Sets the bottom of the AM band for seek. Default is 520 kHz. Range: 520–1710 (MW). 144–288 (LW). 2300–30000 (SW). Property 0x1101 AM_SEEK_BAND_TOP The AM_SEEK_BAND_TOP property sets the top of the AM band for seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 1710 kHz Default: 1710 Units: kHz 15 14 13 12 11 10 AM_SEEK_BAND_TOP 9 8 7 6 AMSKFREQH[15:0] 5 4 3 2 1 0 0x06AE Bit 15:0 Name AMSKFREQH[15:0] Function Sets the top of the AM band for seek. Default is 1710 kHz. Range: 520–1710 (MW). 144–288 (LW) 2300–30000 (SW) Rev. 0.3 159 AN645 Property 0x1102 AM_SEEK_FREQUENCY_SPACING The AM_SEEK_FREQUENCY_SPACING property selects frequency spacing for AM seek in multiples of 1 kHz. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 10 kHz. Default: 10 Units: kHz AM_SEEK_FREQUENCY_SPACING 15 14 13 12 Bit Name 15:5 Reserved 4:0 160 11 AMSKSPACE[4:0] 10 9 8 7 6 5 4 3 2 1 0x000 AMSKSPACE[4:0] 0x000 0x0A 0 Function Always write 0. Selects frequency spacing for AM seek. Default is 10 kHz. Range is 1–31. 5 = SW (5 kHz). 9 = AM in Asia (9 kHz). 9 = LW (9 kHz). 10 = AM in U.S. (10 kHz). Rev. 0.3 AN645 Property 0x1200 AM_RSQ_INTERRUPT_SOURCE The AM_RSQ_INTERRUPT_SOURCE property configures interrupt related to Received Signal Quality metrics. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 0. Default: 0 AM_RSQ_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 5 0x000 4 3 2 1 0 SNRHINT SNRLINT RSSIHINT RSSILINT 0x000 0 0 0 0 Bit Name 15:4 Reserved Always write 0. 3 SNRHINT 0: Disable Interrupt. 1: Enable interrupt to occur if SNR goes above the threshold set by AM_RSQ_SNR_HIGH_THRESHOLD. 2 SNRLINT 0: Disable Interrupt. 1: Enable interrupt to occur if SNR goes below the threshold set by AM_RSQ_SNR_LOW_THRESHOLD. 1 RSSIHINT 0: Disable Interrupt. 1: Enable interrupt to occur if RSSI goes above the threshold set by AM_RSQ_RSSI_HIGH_THRESHOLD. RSSILINT 0: Disable Interrupt. 1: Enable interrupt to occur if RSSI goes below the threshold set by AM_RSQ_RSSI_LO_THRESHOLD. 0 Function Rev. 0.3 161 AN645 Property 0x1201 AM_RSQ_SNR_HIGH_THRESHOLD The AM_RSQ_SNR_HIGH_THRESHOLD property sets the high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Units: dB 15 14 13 12 11 0x00 AM_RSQ_SNR_HIGH_THRESHOLD 10 9 8 7 6 5 4 3 SNRH[7:0] 0x00 Bit Name 15:8 Reserved 7:0 SNRH [7:0] 2 1 0 0x7F Function Write 0 for (+) values, 0xFF for (–) values. Sets the high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. Default is 127 dB. Range is –128 to 127 dB in steps of 1 dB. Property 0x1202 AM_RSQ_SNR_LOW_THRESHOLD The AM_RSQ_SNR_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if the SNR is below this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –128 Units: dB AM_RSQ_SNR_LOW_THRESHOLD 15 14 13 12 10 9 8 7 6 5 4 3 0xFF SNRL[7:0] 0xFF 0x80 Bit Name 15:8 Reserved 7:0 SNRL [7:0] 162 11 2 1 0 Function Write 0 for (+) values, 0xFF for (–) values. Sets low threshold, which triggers the RSQ interrupt if the SNR is below this threshold. Default is –128 dB. Range is –128 to 127 dB in steps of 1 dB. Rev. 0.3 AN645 Property 0x1203 AM_RSQ_RSSI_HIGH_THRESHOLD The AM_RSQ_RSSI_HIGH_THRESHOLD property sets high threshold, which triggers the RSQ interrupt if the RSSI is above this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Units: dBµV AM_RSQ_RSSI_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 0x00 RSSIH[7:0] 0x00 0x7F Bit Name 15:8 Reserved 7:0 RSSIH [7:0] 2 1 0 Function Write 0 for (+) values, 0xFF for (–) values. Sets high threshold, which triggers the RSQ interrupt if the RSSI is above this threshold. Default is 127 dBµV. Range is –128 to 127 dBµV in steps of 1 dB. Property 0x1204 AM_RSQ_RSSI_LOW_THRESHOLD The AM_RSQ_RSSI_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if the RSSI is below this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –128 Units: dBµV 15 14 13 12 11 0xFF AM_RSQ_RSSI_LOW_THRESHOLD 10 9 8 7 6 5 4 3 RSSIL[7:0] 0xFF Bit Name 15:8 Reserved 7:0 RSSIL [7:0] 2 1 0 0x80 Function Write 0 for (+) values, 0xFF for (–) values. Sets low threshold, which triggers the RSQ interrupt if the RSSI is below this threshold. Default is –128 dBµV. Range is –128 to 127 dBµV in steps of 1 dB. Rev. 0.3 163 AN645 Property 0x1300 AM_ACF_INTERRUPT_SOURCE The AM_ACF_INTERRUPT_SOURCE property enables the ACF interrupt sources. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 AM_ACF_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 5 4 0x0000 2 1 0 HICUT_INT CHBW_INT SOFTMUTE_INT 0x0000 0 0 0 Bit Name 15:3 Reserved 2 HICUT_INT When set, enables the Hi-cut Interrupt. Default is 0. 0 = The Hi-cut interrupt is disabled. 1 = The Hi-cut interrupt is enabled. 1 CHBW_INT When set, enables the Channel Filter Bandwidth Interrupt. Default is 0. 0 = The Channel Filter Bandwidth interrupt is disabled. 1 = The Channel Filter Bandwidth interrupt is enabled. 0 164 3 SOFTMUTE_INT Function Always write 0. When set, enables the softmute interrupt. Default is 0. 0 = The softmute interrupt is disabled. 1 = The softmute interrupt is enabled. Rev. 0.3 AN645 Property 0x1301 AM_ACF_SM_THRESHOLD The AM_ACF_SM_THRESHOLD property sets the softmute interrupt threshold in dB. When softmute attenuation rises above the level set by this property and the SOFTMUTE_INT interrupt is enabled through the AM_ACF_INTERRUPT_SOURCE property, the SOFTMUTE_INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 31 Units: dB AM_ACF_SM_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0x000 SMATTN_THRESH[4:0] 0x000 0x1F Bit Name 15:5 Reserved 0 Function Always write 0. Softmute interrupt threshold in dB which triggers the softmute interrupt when SMATTN_THRESH[4:0] the softmute attenuation rises above this level. Default is 31 dB. Range is 0–31 dB. 4:0 Property 0x1302 AM_ACF_CHBW_THRESHOLD The AM_ACF_CHBW_THRESHOLD property sets the Channel Filter Bandwidth interrupt threshold in units of 100 Hz. When the channel filter bandwidth falls below this threshold and the CHBW_INT interrupt is enabled through the AM_ACF_INTERRUPT_SOURCE property, the CHBW_INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: 100 Hz AM_ACF_CHBW_THRESHOLD 15 14 13 12 10 9 8 7 6 5 4 3 2 0x00 CHBW_THRESH[7:0] 0x00 0x00 Bit Name 15:8 Reserved 7:0 11 1 0 Function Always write 0. Channel Filter Bandwidth interrupt threshold in units of 100 Hz, which trigCHBW _THRESH[7:0] gers the Channel Filter Bandwidth Interrupt when the channel filter bandwidth falls below this threshold. Default is 0 kHz. Range is 0–255. Rev. 0.3 165 AN645 Property 0x1303 AM_ACF_HICUT_THRESHOLD The AM_ACF_HICUT_THRESHOLD property sets the Hi-cut interrupt threshold in units of 100 Hz. When the Hicut cutoff frequency falls below this threshold and the Hi-cut_INT interrupt is enabled through the AM_ACF_INTERRUPT_SOURCE property, the Hi-cut_ INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: 100 Hz AM_ACF_HICUT_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 0x00 HICUT_THRESH[7:0] 0x00 0x00 Bit Name 15:8 Reserved 1 0 Function Always write 0. Hi-cut interrupt threshold in units of 100 Hz, which triggers the Hi Cut InterHICUT_THRESH[7:0] rupt when the Hi-cut cutoff frequency falls below this threshold. Default is 0 kHz. Range is 0–200. 7:0 Property 0x1306 AM_ACF_CONTROL_SOURCE The AM_ACF_CONTROL_SOURCE property determines if SNR or RSSI will be used as the controlling metric for ACF features. This will affect all automatically controlled features that are controlled by SNR. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 AM_ACF_CONTROL_SOURCE 15 166 14 13 12 Bit Name 15:1 Reserved 0 USE_RSSI 11 10 9 8 7 6 5 4 3 2 1 0 0x0000 USE_RSSI 0x0000 0 Function Always write 0. When set, RSSI will be used instead of SNR as the ACF controlling metric. 0 = Use SNR as the controlling metric. 1 = Use RSSI as the controlling metric. Rev. 0.3 AN645 Property 0x2000 AM_VALID_MAX_TUNE_ERROR The AM_VALID_MAX_TUNE_ERROR property sets the maximum frequency error allowed in units of 2 ppm before setting the AFC rail indicator (AFCRL). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 75 (150 ppm) Units: 2 ppm AM_VALID_MAX_TUNE_ERROR 15 14 13 12 11 10 9 8 7 6 5 4 3 2 0x00 AMMAXTUNEERR[7:0] 0x00 0x4B Bit Name 15:8 Reserved 7:0 AMMAXTUNEERR [7:0] 1 0 Function Always write 0. Sets the maximum freq error allowed in units of 2 ppm before setting the AFC rail indicator (AFCRL). Default is 75. Range is 0–126. Property 0x2003 AM_VALID_SNR_THRESHOLD The AM_VALID_SNR_THRESHOLD property sets the SNR threshold for a valid AM Seek/Tune. If the desired channel SNR is above this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 5 Units: dB AM_VALID_SNR_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 0x00 AMVALSNR[7:0] 0x00 0x05 Bit Name 15:8 Reserved 7:0 AMVALSNR [7:0] 2 1 0 Function Write 0 for (+) values, 0xFF for (–) values. Sets the SNR threshold for a valid AM Seek/Tune. Default is 5 dB. Range is –128 to 127 in steps of 1 dB. –128 = SNR is not used as a criterion in determining the validity of a station. Rev. 0.3 167 AN645 Property 0x2004 AM_VALID_RSSI_THRESHOLD The AM_VALID_RSSI_THRESHOLD property sets the RSSI threshold for a valid AM Seek/Tune. If the desired channel RSSI is above this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 10 Units: dBµV AM_VALID_RSSI_THRESHOLD 15 14 13 12 10 9 8 7 6 5 4 3 0x00 AMVALRSSI[7:0] 0x00 0x0A Bit Name 15:8 Reserved 7:0 11 2 1 0 Function Write 0 for (+) values, 0xFF for (–) values. AMVALRSSI[7:0] Sets the RSSI threshold for a valid AM Seek/Tune. Default is 10 dBµV. Range is –128 to 127 in steps of 1 dB. –128 = RSSI is not used as a criterion in determining the validity of a station. Property 0x2200 AM_CHBW_SQ_MIN_MAX The AM_CHBW_SQ_MIN_MAX property sets the maximum and minimum channel filter bandwidth in units of 100 Hz based on SNR or RSSI. To force a given channel filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x2314 Units: 100 Hz AM_CHBW_MIN_MAX 15 168 14 13 12 11 10 9 8 7 6 5 4 3 MAX[7:0] MIN[7:0] 0x23 0x14 2 1 Bit Name Function 15:8 MAX [7:0] Sets the maximum channel filter bandwidth in units of 100 Hz. Default is 3.5 kHz. Range is 15–50. 7:0 MIN [7:0] Sets the minimum channel filter bandwidth in units of 100 Hz. Default is 2 kHz. Range is 15–50. Rev. 0.3 0 AN645 Property 0x2201 AM_CHBW_SQ_HIGH_THRESHOLD The AM_CHBW_SQ_HIGH_THRESHOLD property sets the SNR or RSSI threshold for maximum channel filter bandwidth. If the SNR or RSSI reported by the device is greater than the SQ High threshold programmed, then the channel filter bandwidth will be set to the maximum value programmed through Property 0x2200. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 30 Units: dB (for SNR), dBµV (for RSSI) AM_CHBW_SQ_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 SQMAX[6:0] 0x001E Bit Name 15:0 SQMAX[15:0] Function Sets the SNR or RSSI threshold for maximum channel filter bandwidth. Default is 30 dB. Range is 0–127 dB (or dBµV for RSSI). Property 0x2202 AM_CHBW_SQ_LOW_THRESHOLD The AM_CHBW_SQ_LOW_THRESHOLD property sets the SNR or RSSI threshold for minimum channel filter bandwidth. If the SNR or RSSI reported by the device is less than the SQ Low threshold programmed, then the channel filter bandwidth will be set to the minimum value programmed through Property 0x2200. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 15 Units: dB (for SNR), dBµV (for RSSI) AM_CHBW_SQ_LOW_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 SQMIN[6:0] 0x000F Bit Name Function 15:0 SQMIN[15:0] Sets the SNR or RSSI threshold for minimum channel filter bandwidth. Default is 15 dB. Range is 0–127 dB (or dBµV for RSSI). Rev. 0.3 169 AN645 Property 0x2203 AM_CHBW_SQ_WIDENING_TIME The AM_CHBW_SQ_WIDENING_TIME property sets the channel filter bandwidth widening time based on SNR or RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 2048 Units: ms AM_CHBW_SQ_WIDENING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 WIDENING_TIME[15:0] 0x0800 Bit Name Function 15:0 WIDENING_TIME[15:0] Sets the SNR or RSSI based channel filter bandwidth widening time. Default is 2048 ms. Range is 1–32767 ms. Property 0x2204 AM_CHBW_SQ_NARROWING_TIME The AM_CHBW_SQ_NARROWING_TIME property sets the channel filter bandwidth narrowing time based on SNR or RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms AM_CHBW_SQ_NARROWING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 NARROWING_TIME[15:0] 0x0010 170 Bit Name Function 15:0 NARROWING_TIME [15:0] Sets the SNR or RSSI based channel filter bandwidth narrowing time. Default is 16 ms. Range is 1–32767 ms. Rev. 0.3 AN645 Property 0x2205 AM_CHBW_ASSI_MIN_MAX The AM_CHBW_ASSI_MIN_MAX property sets the maximum and minimum channel filter bandwidth in units of 100 Hz. Based on adjacent signal strength indicator (ASSI.) To force a given channel filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x3232 Units: 100 Hz AM_CHBW_ASSI_MIN_MAX 15 14 13 12 11 10 9 8 7 6 5 4 3 MAX[7:0] MIN[7:0] 0x32 0x32 2 1 0 Bit Name Function 15:8 MAX[7:0] Sets the maximum channel filter bandwidth in units of 100 Hz. Default is 5 kHz. Range is 15–100. 7:0 MIN[7:0] Sets the minimum channel filter bandwidth in units of 100 Hz. Default is 5 kHz. Range is 15–100. Property 0x2206 AM_CHBW_ASSI_LOW_THRESHOLD The AM_CHBW_ASSI_LOW_THRESHOLD property sets the ASSI threshold in dB for maximum channel filter bandwidth. If the ASSI reported by the device is less than the ASSI Low threshold programmed, then the channel filter bandwidth will be set to the maximum value programmed through Property 0x2205. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 10 Units: dB AM_CHBW_ASSI_LOW_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ASSIMIN[15:0] 0x000A Bit Name 15:0 ASSIMIN[15:0] Function Sets the ASSI threshold for maximum channel filter bandwidth. Default is 10 dB. Range is –128 to 127 dB. Rev. 0.3 171 AN645 Property 0x2207 AM_CHBW_ASSI_HIGH_THRESHOLD The AM_CHBW_ASSI_HIGH_THRESHOLD property sets the ASSI threshold in dB for minimum channel filter bandwidth. If the ASSI reported by the device is greater than the ASSI High threshold programmed, then the channel filter bandwidth will be set to the minimum value programmed through Property 0x2205. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 30 Units: dB AM_CHBW_ASSI_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ASSIMAX[15:0] 0x001E Bit Name Function 15:0 ASSIMAX[15:0] Sets the ASSI threshold for minimum channel filter bandwidth. Default is 30 dB. Range is –128 to 127 dB. Property 0x2208 AM_CHBW_ASSI_WIDENING_TIME The AM_CHBW_ASSI_WIDENING_TIME property sets the channel filter bandwidth widening time based on ASSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms AM_CHBW_ASSI_WIDENING_TIME 15 14 13 12 11 10 9 8 7 6 5 WIDENING[15:0] 0x0010 172 Bit Name 15:0 WIDENING[15:0] Function Sets the channel filter widening time in ms. Default is 16 ms. Range is 1–32767 ms. Rev. 0.3 4 3 2 1 0 AN645 Property 0x2209 AM_CHBW_ASSI_NARROWING_TIME The AM_CHBW_ASSI_NARROWING_TIME property sets the channel filter bandwidth narrowing time based on ASSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms AM_CHBW_ASSI_NARROWING_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 NARROWING[15:0] 0x0010 Bit Name Function 15:0 NARROWING[15:0] Sets the channel filter narrowing time in ms. Default is 16 ms. Range is 1–32767 ms. Property 0x3100 AM_HICUT_SQ_HIGH_THRESHOLD The AM_HICUT_SQ_HIGH_THRESHOLD property sets the SNR or RSSI level at which Hi-cut begins to band limit. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8 Units: dB (for SNR), dBµV (for RSSI) AM_HICUT_SQ_HIGH_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 0x000 SQ_HIGH[6:0] 0x000 0x08 Bit Name 15:7 Reserved 6:0 SQ_HIGH[6:0] 1 0 Function Always write 0. Sets the SNR or RSSI level at which Hi-cut begins to band limit. Default is 8. Range is from 0–127 dB (for SNR), dBµV (for RSSI). Rev. 0.3 173 AN645 Property 0x3101 AM_HICUT_SQ_LOW_THRESHOLD The AM_HICUT_SQ_LOW_THRESHOLD property sets the SNR or RSSI level at which Hi-cut reaches maximum band limiting. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: dB AM_HICUT_SQ_LOW_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 0x000 SQ_LOW[6:0] 0x000 0x08 Bit Name 15:7 Reserved 6:0 SQ_LOW[7:0] 1 0 Function Always write 0. Sets the SNR or RSSI level at which Hi-cut reaches maximum band limiting. Default is 0. Range is from 0–127 dB (for SNR), dBµV (for RSSI). Property 0x3102 AM_HICUT_ATTACK_TIME The AM_HICUT_ATTACK_TIME property sets the transition time in ms for which high cut lowers the cutoff frequency. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms AM_HICUT_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 174 Bit Name 15:0 ATTACK[15:0] Function Sets the transition time in ms for which high cut lowers the cutoff frequency. Default is 16 ms. Range is 16–32767 ms. Rev. 0.3 AN645 Property 0x3103 AM_HICUT_RELEASE_TIME The AM_HICUT_RELEASE_TIME property sets the transition time in ms for which high cut increases the cutoff frequency. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 2000 Units: ms AM_HICUT_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x07D0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time in ms for which high cut increases the cutoff frequency. Default is 2000 ms. Range is 16–32767 ms. Property 0x3104 AM_HICUT_CUTOFF_FREQ The AM_HICUT_CUTOFF_FREQ property sets the maximum and minimum Hi-cut transition frequencies in units of 100 Hz. To force a given Hi-cut filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x280A Units: 100 Hz AM_HICUT_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 MAX[7:0] MIN[7:0] 0x28 0x0A Bit Name 15:8 MAX [7:0] Maximum Hi-cut transition frequency in units of 100 Hz. Default is 4 kHz. Range is 10–50. 7:0 MIN [7:0] Minimum Hi-cut transition frequency in units of 100 Hz. Default is 1 kHz. Range is 10–50. 2 1 0 Function Rev. 0.3 175 AN645 Property 0x3105 AM_LOWCUT_MIN_FREQ The AM_LOWCUT_MIN_FREQ property sets the minimum cutoff frequency. The LowCut tracks the HICUT engine; therefore, thresholds are programmed in property 0x3100 and 0x3101. Setting the property to 0 disables LowCut. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0A Units: Hz AM_HICUT_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MIN[15:0] 0x0000 Bit Name Function 15:0 FREQ_MIN[15:0] Sets the minimum LOW-CUT cutoff frequency in Hz. Default is disabled. Range is 0–1000 Hz. 0 = Disabled. Property 0x3106 AM_LOWCUT_MAX_FREQ The AM_LOWCUT_MAX_FREQ property sets the maximum cutoff frequency. The LowCut tracks the HICUT engine, therefore thresholds are programmed in property 0x3100 and 0x3101. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0A Units: Hz AM_HICUT_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MAX[15:0] 0x0000 Bit 15:0 176 Name Function FREQ_MAX[15:0] Sets the maximum LOW-CUT cutoff frequency in Hz. Note that if property 0x3105 (AM_LOWCUT_MIN_FREQ) is non-zero, this property must be set to a value no less than property 0x3105. Default is 0 Hz. Range is 0–1000 Hz. Rev. 0.3 AN645 Property 0x3300 AM_IBOC_CONTROL (Si47777 Only) The AM_IBOC_CONTROL property is the control property for IBOC Blend. DIGITAL_IO_INPUT_SAMPLE_RATE and DIGITAL_IO_INPUT_FORMAT must be configured before IBOC Blend will function. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 AM_IBOC_CONTROL 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x00 FORCE 0x00 ENABLE 0x00 0 0x00 0 Bit Name Function 15:9 Reserved Always write 0. Forces IBOC Blend. Default is 0. 0 = Do not force IBOC blend. The audio source is determined by the IBOC control pin. 1 = Force IBOC blend. The audio comes from IBOC system. 8 Force 7:1 Reserved 0 Enable Always write 0. IBOC Blend Enable. Default is 0. 0 = The IBOC blend system is disabled. 1 = The IBOC blend system is enabled. Property 0x3301 AM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME (Si4777 Only) The AM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME property sets the crossfade time between full analog and full HD Digital audio in milliseconds. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 1000 Units: ms AM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 TIME[15:0] 0x03E8 Bit Name 15:0 TIME[15:0] Function Sets the full analog to full digital crossfade time in ms. Default is 1000 ms. Range is 0–22000 ms. Rev. 0.3 177 AN645 Property 0x3302 AM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME (Si4777Only) The AM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME property sets the crossfade time from full HD Digital to full analog audio in milliseconds. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 1000 Units: ms AM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 TIME[15:0] 0x03E8 Bit Name Function 15:0 TIME[15:0] Sets the full digital to full analog crossfade time in ms. Default is 1000 ms. Range is 0–22000 ms. Property 0x3303 AM_IBOC_DYNAMIC_GAIN (Si47777 Only) The AM_IBOC_DYNAMIC_GAIN property sets the digital audio dynamic linear scaling factor. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x007F AM_IBOC_DYNAMIC_GAIN 15 178 14 13 12 11 10 9 8 7 6 5 4 3 0x00 DGAIN[7:0] 0x00 0x7F Bit Name 15:8 Reserved 7:0 DGAIN[7:0] 2 1 0 Function Always write 0. Station dependent linear scaling factor in Q7 format. Range is 0–0x7F. Rev. 0.3 AN645 Property 0x3304 AM_IBOC_STATIC_GAIN (Si4777 Only) The AM_IBOC_STATIC_GAIN property sets the digital audio static linear gain factor. Reverse the sign of this number to obtain a 180 degree phase shift. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0100 AM_IBOC_STATIC_GAIN 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 SGAIN[15:0] 0x0100 Bit Name Function 15:0 SGAIN[15:0] Static linear gain factor in Q7.8 format. Range is 0x8000–0x7FFF. RESP Bit Name Function 1 7:3 Reserved 1 2 HICUT_INT If set indicates that the Hi-cut cutoff frequency is below the Hicut threshold set by WB_ACF_HICUT_THRESHOLD. 1 1 CHBW_INT If set indicates that the Channel Filter Bandwidth is less than the threshold set by WB_ACF_CHBW_THRESHOLD. 1 0 SOFTMUTE_INT 2 7:1 Reserved 2 0 SMUTE 3 7:0 SMATTN[7:0] Soft mute attenuation level in dB. Range: 0–31. 4 7:0 CHANBW[7:0] Channel filter bandwidth in 100 Hz. Range: 0–150. 5 7:0 HICUT [7:0] Values may vary. Is set Indicates that softmute attenuation has increased above the softmute threshold as set by WB_ACF_SM_THRESHOLD. Values may vary. 0 = Audio is not soft muted. 1 = Audio is soft muted. Hi-cut cutoff frequency in units of 100 Hz. Range: 10–50. Rev. 0.3 179 AN645 10. Programming Examples Table summarizes descriptions and programming examples in this section. Table 18. Configuration and Operation Examples Section Description Operation Configuration 180 10.1.1 Analog/Digital/MPX audio 10.1.2 IBOC HD Radio 10.1.3 AGC 10.1.4 Interrupts 10.1.5 Noise Blankers 10.1.6 Channel Equalizer 10.1.7 Pop Filter 10.1.8 Channel Filter Bandwidth 10.1.9 Softmute 10.1.10 Automatic Volume Control (AVC) 10.1.11 Blend 10.1.12 Hi-cut 10.1.13 Hi-blend 10.1.14 Primary/Companion 10.2.1 Tune 10.2.2 Seek 10.2.3 RDS 10.2.5 Check CTS and ERR 10.2.6 Check STC Rev. 0.3 AN645 10.1. Configuration The following tables summarize the available configuration options for AM and FM functions. Refer to section “9. Commands and Properties”for detailed descriptions of commands and properties. Table 19. FM Configuration Commands and Properties Pin Configuration Commands Properties Interrupts 0x1C 0x0000 GPIO Configuration 0x1A Analog/MPX audio 0x1B Digital audio 0x18 0x0200 ZIF 0x19 0x0600 RF/Audio Configuration Commands Properties Softmute 0x0400 RF Signal routing, AGC thresholds and timing 0x0700 Channel spacing 0x1100 RSQ (RSSI, SNR) Interrupts 0x1200 ACF (Softmute, Channel Filter Bandwidth, Hi-blend, Hi-cut) Interrupts 0x1300 Tune/seek metric thresholds and timing (RSSI, SNR, frequency error) 0x2000 Channel filter bandwidth (RSSI, SNR, ASSI, ASSI200) range and timing 0x2200 Channel Equalizer 0x3400 Blend (RSSI/SNR, Multi-path, USN) range and timing 0x3500 Hi-cut (RSSI/SNR, Multi-path, USN) range and timing 0x3600 Hi-blend (RSSI/SNR, Multi-path, USN) range and timing 0x3700 IBOC Configuration Commands IBOC (cross-fade timing, dynamic and static gains) RDS Configuration 0x3300 Commands RDS Interrupts, FIFO size and management, decoder configuration Rev. 0.3 Properties Properties 0x4000 181 AN645 Table 20. AM Configuration Commands and Properties Pin Configuration Commands Properties Interrupts 0x1C 0x0000 GPIO Configuration 0x1A Analog audio 0x1B Digital audio 0x18 0x0200 ZIF 0x19 0x0600 RF/Audio Configuration Commands Properties Power line filtering 0x0300 Softmute 0x0400 AVC (automatic volume control) 0x0500 RF Signal routing, AGC thresholds and timing 0x0700 Channel spacing 0x1100 RSQ (RSSI, SNR) Interrupts 0x1200 ACF (Softmute, Channel Filter Bandwidth, Hi-cut) Interrupts 0x1300 Tune/seek metric thresholds and timing (RSSI, SNR, frequency error) 0x2000 Channel filter bandwidth (RSSI, SNR, ASSI) range and timing 0x2200 Hi-cut (RSSI/SNR) range and timing 0x3100 IBOC Configuration Commands Properties IBOC (cross-fade timing, dynamic and static gains) 182 Rev. 0.3 0x3300 AN645 10.1.1. Analog/Digital/MPX audio Analog, digital and MPX audio setup includes pin and sample rate (if applicable) configuration. 1. Complete steps up to and including 5 in section 5.1 Powerup one Receiver from Internal Memory or 10 in section 5.2 Powerup one Receiver from a Patch. 2. Send the ANA_AUDIO_PIN_CFG command to route analog left and right channel to LOUT/ROUT pins, or to route the MPX to the LOUT pin. This step may be omitted if analog audio is not required. Example: ANA_AUDIO_PIN_CFG Command Action Data Description CMD 0x1B ANA_AUDIO_PIN_CFG ARG1 0x02 2 = LOUT/ROUT pins configured to output audio. 3 = LOUT is configured for MPX out and ROUT is disabled. STATUS →0x80 1. Send the DIG_AUDIO_PIN_CFG command to configure DCLK, DFS and DOUT for digital audio in slave mode. Note that DCLK and DFS inputs should be stable before sending this command. This step may be omitted if digital audio is not required. Example: DIG_AUDIO_PIN_CFG Command Action Data Description CMD 0x18 DIG_AUDIO_PIN_CFG ARG1 0x0A 0x0A = configure DCLK pin for digital audio slave mode. ARG2 0x0A 0x0A = configure DFS pin for digital audio slave mode. ARG3 0x0C 0x0C = configure DOUT pin for digital out. ARG3 0x00 0x00 = Do not modify the behavior of the BLEND pin. STATUS →0x80 1. Set property 0x0202 DIGITAL_IO_OUTPUT_SAMPLE_RATE to set the sample rate and 0x0203 DIGITAL_IO_OUTPUT_FORMATS to set the bit width and justification. This step may be omitted if digital audio is not required. 2. Proceed to other examples in this section. Rev. 0.3 183 AN645 10.1.2. IBOC HD Radio IBOC HD radio setup requires configuration of input and output sample rates, I2S digital audio input and blend control from the IBOC demodulator, I2S blended audio input to the system audio processor. Figure 16 shows a conceptual diagram of the hardware interconnects. HD Radio Demod QOUT (Pin 26) IOUT (Pin 25) IQFS (Pin24) IQCLK (Pin 23) Digital I/Q ZIF (I2S) Demod Audio /Data Decoders Master 4-wire mode Master Si4777 X 3-wire mode AM/FM Analog demodulation Weak signal processing IBOC blend HD audio ASRC PLL BLEND (Pin 30) DCLK (Pin 29) DFS (Pin 28) DIN (Pin 27) Blend Flag Digital bit clock Digital frame sync HD audio AM/FM audio ASRC DOUT2 (Pin 14) DCLK2 (Pin 13) DFS2 (Pin 18) Blended audio Digital bit clock Digital frame sync Audio processing Blended audio DSP Master Figure 16. System Implementation of HD-Radio Reception with IBOC Blend on the Si47777 1. Complete steps up to and including 5 in section “5.1. Powerup from Internal Memory”or 10 in section “5.2. Powerup from a Patch”. 2. Set property 0x0301 AUDIO_MUTE. 184 Rev. 0.3 AN645 Example: SET_PROPERTY Command Action Data Description CMD 0x13 SET_PROPERTY ARG1 0x00 ARG2 0x03 ARG3 0x01 ARG4 0x00 ARG5 0x03 STATUS →0x80 0x0301 = AUDIO MUTE 0x0003 = Mute left and right 3. Set property 0x0200 DIGITAL_IO_INPUT_SAMPLE_RATES and 0x0202 DIGITAL_IO_OUTPUT_SAMPLE_RATE to configure the input and output digital sample rates. Example: SET_PROPERTY Command Action Data Description CMD 0x13 SET_PROPERTY ARG1 0x00 ARG2 0x02 ARG3 0x00 ARG4 0xAC ARG5 0x44 STATUS →0x80 0x0200 = DIGITAL_IO_INPUT_SAMPLE_RATES 0xAC44 = 44.1 kHz SET_PROPERTY Command Action Data Description CMD 0x13 SET_PROPERTY ARG1 0x00 ARG2 0x02 ARG3 0x02 ARG4 0xAC ARG5 0x44 STATUS →0x80 0x0202 = DIGITAL_IO_OUTPUT_SAMPLE_RATES 0xAC44 = 44.1 kHz 4. Send the DIG_AUDIO_PIN_CFG command to configure DCLK, DFS and DIN for I2S audio input in slave mode and the BLEND pin to select the mode of the audio combiner. Note that DCLK and DFS inputs Rev. 0.3 185 AN645 should be stable before sending this command. Example: DIG_AUDIO_PIN_CFG Command Action Data Description CMD 0x18 DIG_AUDIO_PIN_CFG ARG1 0x0A 0x0A = configure DCLK pin 29 for digital audio in slave mode. ARG2 0x0A 0x0A = configure DFS pin 28 for digital audio in slave mode. ARG3 0x0D 0x0D = configure DIN pin 27 for digital in. ARG3 0x17 0x17 = configure BLEND pin 30 to select the mode of the audio combiner (analog or HD). STATUS →0x80 5. Send the ZIF_PIN_CFG command to configure IOUT, QOUT, IQCLK and IQFS pins for ZIF output in I2S master mode. Example: ZIF_PIN_CFG Command Action Data Description CMD 0x19 ZIF_PIN_CFG ARG1 0x15 0x15 = configure IQCLK pin 23 for I/Q output in master mode. ARG2 0x15 0x15 = configure IQFS pin 24 for I/Q output in master mode. ARG3 0x16 0x16 = configure IOUT pin 25 for I/Q output in master mode. ARG3 0x16 0x16 = configure QOUT pin 26 for I/Q output in master mode. STATUS →0x80 6. Send the IC_LINK_GPIO_CTL_PIN_CFG command to configure DCLK2 and DOUT2 pins in I2S slave mode. Note that the DCLK2 input should be stable before sending this command. 186 Rev. 0.3 AN645 Example: GPIO_CTL_PIN_CFG Command Action Data Description CMD 0x1A GPIO_CTL_PIN_CFG ARG1 0x00 ARG2 0x00 ARG3 0x0A 0x0A = Configure ICON pin as DCLK2 in slave mode. ARG4 0x0E 0x0E = Configure ICOP pin as DOUT2 in slave mode. STATUS →0x80 7. Send the INTB_PIN_CFG command to configure DFS2 in I2S slave mode. Note that the DFS2 input should be stable before sending this command. In this example, the interrupt pin is set to the A1 pin. Note that only the A0 pin is available for I2C address selection in this mode. Note also that the interrupt pin can be moved to the A1 pin with a POWER_UP option. Example: INTB_PIN_CFG Command Action Data Description CMD 0x1C INTB_PIN_CFG ARG1 0x0A 0x0A = Configure the DFS2 pin 18 for digital audio in slave mode. ARG2 0x28 0x28 = Configure the A1 pin as the interrupt. ARG3 0x00 ARG4 0x00 STATUS →0x80 8. Enable the IBOC blend system. SET_PROPERTY Command Action Data Description CMD 0x13 SET_PROPERTY ARG1 0x00 ARG2 0x33 ARG3 0x00 ARG4 0x00 ARG5 0x01 STATUS →0x80 0x01 = enable 9. Note that tuning requires setting the HD bit for proper bandwidth configuration. See Section 9.2.1 Tune. Proceed to other examples in this section. Rev. 0.3 187 AN645 10.1.3. AGC For FM mode, the AGC default configuration is generally optimal. The following section describes the settings and options. AGC settings may be over-ridden by setting property 0x0710 FM_AGC_OVERRIDE and the state of the AGC peak detectors may be monitored by sending command 0x17 AGC_STATUS. 10.1.3.1. FM FM AGC configuration involves setting signal routing, AGC and peak detector. The default property settings are configured for routing through the LNA input (instead of directly to the mixer) with 50 Ω LNA impedance as shown in Figure 17. FMAGC2 FMAGC1 FMVAR FMXIP RF Pkd FMXIN RFREG Reg RL FMO LNA 50 FMI to AM RF Pkd Si477x Figure 17. FM Single Receiver System Diagram For optimal weak signal, blocker and intermodulation performance, the default property settings are configured to disable the LNA peak detector and associated attack/release time constants, and enable the mixer peak detector thresholds to 85 dBµV and 3 dB hysteresis, with an attack time of 4 ms and release time of 80 ms. To improve weak signal performance at the expense of intermodulation performance, the mixer peak detector thresholds may be increased to as high as 93 dBµV. To improve blocker and intermodulation performance at the expense of weak signal performance, the mixer peak detector thresholds may be decreased to as low as 79 dBµV. To improve impulsive noise desensitization (caused by engaging the AGC) at the expense of AGC response time, the mixer peak detector attack time may be increased from 4 ms to an attack time greater than the period of the impulses. 188 Rev. 0.3 AN645 10.1.3.2. AM AM AGC configuration involves configuring signal routing, AGC and peak detector characteristics. The default property settings are configured for optimal performance with the harmonic rejection enabled, IF AGC attack time of 80 ms and release time of 804 ms, RF attack time of 8 ms and RF release time of 800 ms. 10.1.4. Interrupts The interrupt status can be monitored by sending command 0x15 GET_INT_STATUS. Note that the command response varies based on FM or AM mode. Interrupt pins can be configured by sending command 0x1C INTB_PIN_CFG. Property 0x0000 INT_CTL_ENABLE enables top-level interrupt sources and interrupt repetition characteristics. Property group 0x1200 configures RSQ (RSSI, SNR) interrupts. Property group 0x1300 configures ACF (Softmute, Channel Filter Bandwidth, Hi-blend, Hi-cut) interrupts. Note that Hi-blend only applies to FM mode operation. Property group 0x4000 configures RDS interrupts. 10.1.5. Channel Equalizer Property 0x3400 enables and disables the FM multipath channel equalizer. Multi-path interference results in frequency-selective and frequency-flat fading of the FM signal at the receiver. Frequency-selective fading causes different frequencies of an input signal to be attenuated and phase shifted differently in a channel. Frequency-selective fading gives rise to notches in the frequency response of the channel. The channel equalizer performs blind equalization utilizing proprietary constant modulus algorithm (CMA) to restore the flat response of the channel. The channel equalizer is enabled when multipath > 8% and disabled when multipath < 4% for stereo, when multipath > 30% and disabled when multipath < 25% for mono, enabled when max(LASSI, HASSI) > 30 dB and disabled when max(LASSI, HASSI) < 20 dB, enabled when ASSI200 > 50 dB and disabled when ASSI200 < 40 dB. Stereo is set if the PLL is locked or there is significant energy at the pilot. If any condition is satisfied, the channel equalizer will be enabled. Table 21 summarizes the metric conditions that will enable the equalizer. Table 21. Equalizer Enable Conditions Metric Enable Threshold Disable Threshold Multipath (Stereo) > 8% < 4% Multipath (Mono) > 30% < 25% max (LASSI, HASSI) > 30 dB < 20 dB ASSI200 > 50 dB < 40 dB Rev. 0.3 189 AN645 10.1.6. Channel Filter Bandwidth 10.1.6.1. FM Property group 0x2200 configures channel filter bandwidth characteristics for FM mode. Five independent channel filter bandwidth engines can be configured using RSSI (weak signal engine), ASSI100 (absolute value of difference between ±100 kHz channel RSSI), ASSI200 (sum of ±200 kHz channel RSSI minus desired channel RSSI), and 200 kHz blocker deviation as the metric. For RSSI, ASSI100, and ASSI200, channel filter bandwidth ranging from minimum to maximum occurs at the specified widening rate as the metric increases above the minimum threshold and reaches maximum threshold. Channel filter bandwidth ranging from maximum to minimum occurs at the specified narrowing rate as the metric decreases below the maximum threshold and reaches the minimum threshold. For 200 kHz blocker deviation, channel filter bandwidth ranging from 80 to 32 kHz occurs at 1 ms rate as the metric increases above 75 kHz and reaches 100 kHz. Channel filter bandwidth ranging from 32 to 80 kHz occurs at the 300 ms rate as the metric decreases below 100 kHz and reaches 75 kHz. The resulting channel filter bandwidth is the minimum of the result of the five blend engine calculations. Property 0x220F FM_CHBW_WEAKSIG_THR is used to set the hysteresis window for enabling the weak signal RSSI engine. The default is to enable above 16 dBuV RSSI and disable below 14 dBµV RSSI. Note that this hysteresis range is always determined by RSSI and is not configurable with the FM_ACF_CONTROL_SOURCE property. Property 0x2210 FM_CHBW_BLOCKER_THR is used to set the hysteresis window for engaging the 200 kHz blocker engine. The default is to enable above 20 dB ASSI200 and disable below 10 dB ASSI200. Note that 2 dB ASSI200 indicates that the sum of the energy at +200 kHz and –200 kHz is 20 dB greater than the desired channel. The 200 kHz blocker deviation engine is only enabled when sufficient pilot energy is present on the desired channel. 10.1.6.2. AM Property group 0x2200 configures channel filter bandwidth characteristics for AM mode. Two independent channel filter bandwidth engines can be configured using RSSI or SNR and ASSI (independent ±9/10 kHz channel RSSI relative to on-channel RSSI). Channel filter bandwidth ranging from minimum to maximum occurs at the specified widening rate as the metric increases above the minimum threshold and reaches maximum threshold. Channel filter bandwidth ranging from maximum to minimum occurs at the specified narrowing rate as the metric decreases below the maximum threshold and reaches the minimum threshold. The resulting channel filter bandwidth is the minimum of the result of the two blend engine calculations. Property 0x1306 AM_ACF_CONTROL_SOURCE is used to select RSSI or SNR as a metric for the channel filter bandwidth. 10.1.7. Softmute Property group 0x0400 configures softmute characteristics for FM and AM modes. Property 0x1306 FM_ACF_CONTROL_SOURCE (or AM_ACF_CONTROL_SOURCE is used to select SNR (default) or RSSI as a metric for the softmute engine. For FM and AM modes, the property is also used to select whether an AFC rail condition will engage softmute. The most common cause for an AFC rail condition is tuning to an idle channel. Softmute engages as SNR (or RSSI) drops below a trigger threshold and audio level reaches a maximum attenuation at the end threshold. Softmute releases as SNR (or RSSI) rises above the end threshold and audio level reaches full level at the trigger threshold. The attack and release rates are configurable along with maximum attenuation and trigger and end thresholds. 190 Rev. 0.3 AN645 10.1.8. Automatic Volume Control (AVC) Property group 0x0500 configures automatic volume control (AVC) for AM mode. The AVC minimum and maximum gain can be configured. The AVC maintains a constant carrier level. 10.1.9. Mono/stereo Blend Property group 0x3500 configures the mono/stereo blend characteristics for FM mode. Three independent blend engines can be configured with rates using RSSI, multipath, and USN as the metric. Blend from minimum stereo to maximum stereo separation occurs at the specified attack rate as the metric increases above the minimum threshold and reaches maximum threshold. Blend from maximum stereo to minimum stereo separation occurs at the specified release rate as the metric decreases below the maximum threshold and reaches the minimum threshold. The resulting stereo separation is the minimum of the result of the six blend engine calculations. 10.1.10. Hi-cut Hi-cut applies a lowpass filter to the L+R MPX audio. 10.1.10.1. FM Property group 0x3600 configures the Hi-cut characteristics for FM mode. Three independent blend engines can be configured with rates using RSSI, multipath, and USN as the metric. Hicut from minimum to maximum occurs at the specified attack rate as the metric increases above the minimum threshold and reaches maximum threshold. Hi-cut from maximum to minimum occurs at the specified release rate as the metric decreases below the maximum threshold and reaches the minimum threshold. The resulting Hi-cut is the minimum of the result of the six blend engine calculations. 10.1.10.2. AM Property group 0x3100 configures the Hi-cut characteristics for AM mode. The blend engine can be configured with RSSI or SNR as the metric. Hi-cut from minimum to maximum occurs at the specified attack rate as the metric increases above the minimum threshold and reaches maximum threshold. Hi-cut from maximum to minimum occurs at the specified release rate as the metric decreases below the maximum threshold and reaches the minimum threshold. 10.1.11. Hi-blend Hi-blend applies a lowpass filter to the L-R MPX audio. Property group 0x3700 configures the Hi-blend characteristics for FM mode. Three independent blend engines can be configured with rates using RSSI, multipath, and USN as the metric. Hiblend from minimum to maximum occurs at the specified attack rate as the metric increases above the minimum threshold and reaches maximum threshold. Hi-blend from maximum to minimum occurs at the specified release rate as the metric decreases below the maximum threshold and reaches the minimum threshold. The resulting Hiblend is the minimum of the result of the six blend engine calculations. Rev. 0.3 191 AN645 10.2. Operation Operations including sending a command, checking CTS and ERR state, checking STC state, tune, seek, phase diversity receiver mode selection and RDS are possible. 10.2.1. Tune The tune operation provides options for configuring normal FM or HD bandwidth, tuning mode (validated normal tune, unvalidated fast tune) and audio filter state management (re-initialize based on new channel, or smoothly transition from current to new channel). In the case of tuning mode, 0x2000 property group sets the tune/seek metric thresholds and timing (RSSI, SNR, frequency error). Note that references to “AFC Rail” in this manual refers to a condition in which the frequency offset of the desired channel is outside the frequency error as configured with property group 0x2000. Start 1. Configure Tune parameters 2. FM_TUNE_FREQ, or AM_TUNE_FREQ 3. Check CTS & ERR 4. Check STC End 1. Complete the appropriate steps in section “10.1. Configuration”. 2. Send the FM_TUNE_FREQ command to tune to a specific frequency. If the receiver has been muted (for example during IBOC HD configuration), set property 0x0301 to disable mute. Note that AM tuning is very similar. Refer to the AM_TUNE_FREQ command. 192 Rev. 0.3 AN645 Example: FM_TUNE_FREQ Command Action Data Description CMD 0x30 FM_TUNE_FREQ ARG1 0x00 Normal bandwidth (vs. HD bandwidth), unconditionally stay on channel, initialize audio state based on new channel. ARG2 0x27 0x27A6 = tune to 101.50 MHz. ARG3 0xA6 ARG4 0x00 ARG5 0x00 STATUS →0x80 CTS = 1 3. Check the CTS and ERR state to determine whether it is safe to send the next command. Refer to section “10.2.4. Check CTS and ERR Status”. 4. Check the STC state to determine tune status. Refer to section xxx Check STC state. 5. Repeat steps 2, 3, and 4 as necessary. Rev. 0.3 193 AN645 10.2.2. Seek Start 1/2/3. Configure Seek parameters 4. FM_SEEK_START or AM_SEEK_START 5. Check CTS & ERR 6. Check STC End 1. Complete the appropriate steps in section “10.1. Configuration”. 2. Set the 0x1100 property group to configure the seek start, stop and channel spacing. 3. Set the 0x2000 property group to set the tune/seek metric thresholds and timing (RSSI, SNR, frequency error). Note that because every system will have unique signal gain and noise characteristics, RSSI and SNR thresholds should be carefully evaluated. 4. Send the FM_SEEK_START command to begin the seek operation. Example: FM_SEEK_START Command Action Data Description CMD 0x30 FM_SEEK_START ARG1 0x08 Seek up, don’t wrap at the top of the band. STATUS →0x80 CTS = 1 5. Check the CTS and ERR state to determine whether it is safe to send the next command. Refer to section “10.2.4. Check CTS and ERR Status”. 6. Check the STC state to determine seek status and abort if desired. Refer to Check STC state. 7. Repeat steps 4, 5, and 6 as necessary. 194 Rev. 0.3 AN645 10.2.3. RDS 1. Complete the appropriate steps in section “10.1. Configuration”and section “10.2.1. Tune”. 2. Set the 0x4000 property group to configure RDS Interrupts, FIFO size and management, and decoder configuration. 3. (Optional) Send the FM_RDS_BLOCKCOUNT command to verify RDS block error rate. The block error rate is defined as BLER = (UNCORRECTABLE + (EXPECTED-RECEIVED)) / EXPECTED. Example: FM_RDS_BLOCKCOUNT Command Action Data Description CMD 0x37 FM_RDS_BLOCKCOUNT ARG1 0x01 Clear the block count. STATUS →0x80 CTS = 1 RESP1 →0x00 RESP2 →0x27 RESP3 →0x1F RESP4 →0x24 RESP5 →0x8B RESP6 →0x00 RESP7 →0x1B Expected 0x271F = 10015 Received 0x248B = 9355 Uncorrectable 0x001B = 27 Rev. 0.3 195 AN645 In this example, the BLER = (27 + (10015-9355)) / 10015 = 6.8%. 4. Send the FM_RDS_STATUS in response to a configured RDS interrupt or at a set time interval. For example, an interrupt can be configured when the 25 group FIFO has any number of entries between 1 and 25. Alternatively, the command can be sent every 88 ms (time for one group to be received) to 2.2 seconds (time for 25 groups to be received). The FM_RDS_STATUS command must be called once for each entry. The FIFOUSED field can be used to monitor FIFO status. Refer to the RDS and RBDS specifications for further decoding information. Example: FM_RDS_STATUS Command Action Data Description CMD 0x36 FM_RDS_STATUS ARG1 0x01 Acknowledge the STC interrupt. STATUS →0x80 CTS = 1 RESP1 →0x00 RESP2 →0x1A TP/PTY has changed, PI has changed, synchronization has changed. RESP3 →0x05 PTY = 5 RESP4 →0x3E PI = 0x3E67 RESP5 →0x67 RESP6 →0x01 FIFO used = 1 (out of a maximum of 25) RESP7 →0x00 BLEA = 0, BLEB = 0, BLEC = 0, BLED = 0 RESP8 →0x3E BLOCKA = 0x3E67 (PI code) RESP9 →0x67 RESP10 →0x20 RESP11 →0xA7 RESP12 →0x6C RESP13 →0x74 RESP14 →0x65 RESP15 →0x72 BLOCKB = 0x20A7, group 2A (RadioText), PTY = 5, A/B flag = 0, text segment address code = 7 BLOCKC = 0x6C74 (ASCII) = “lt” BLOCKD = 0x6572 (ASCII) = “er” 5. Repeat steps 3 and 4 as necessary. 196 Rev. 0.3 AN645 10.2.4. Check CTS and ERR Status After every command the CTS bit state should be checked to determine whether it is safe to send the next command and the ERR bit state should be checked to determine whether an error has occurred. Start 1. Start Timer 2. Read STATUS and RESP1 3. CTS = 1? No 4 .Timer > 125 ms? No 4. Wait tCTS Yes Yes 5. ERR = 0? 4. STOP No 6. ERR = 0x18? Yes Yes 6. Set CANCEL =1 and call FM_RSQ_STATUS or AM_RSQ_STATUS End 6. Wait 5ms No 7. ERR = 0x20, 0x30 or 0x31? No Yes 7. STOP 6. Set STCACK =1 and call FM_RSQ_STATUS or AM_RSQ_STATUS 6. Wait tCTS Rev. 0.3 197 AN645 1. Start a timer capable of measuring 100 µs to 125 ms. 2. Read the STATUS byte and RESP1. 3. If CTS is set, it is safe to send the next command. Go to step 5. 4. If CTS is not set, check if the timer measures greater than 125 ms (time to execute the POWER_UP command plus 20% margin). If it does, it is likely that the receiver is not in the power up state. Refer to "5. Powerup and Powerdown" on page 4. If it doesn’t, wait time tCTS (100 µs). Refer to "8. Timing" on page 22. 5. If ERR (error) is set, check the specific error code reported in RESP1. 6. If the error code is 0x18, the tune or seek command is in progress and should be aborted by setting CANCEL = 1 and sending the FM_RSQ_STATUS command (or AM_RSQ_STATUS), waiting 5 ms for the seek operation to abort and set the STC bit, acknowledge and clear the STC bit by setting STCACK = 1 and sending the FM_RSQ_STATUS command (or AM_RSQ_STATUS) again, and then waiting time tCTS (100 µs). Refer to "8. Timing" on page 22. 7. If the error code is 0x30 or 0x31 the boot operation failed and the powerup operation should be attempted. Refer to "5. Powerup and Powerdown" on page 4. If the error code is 0x20 contact Silicon Labs. All other errors are recoverable. and the error code reported in RESP1 will clear when the next valid command is sent. See Table 22. Table 22. Error Codes and Remedies RESP1 Error Code Explanation and Remedy 0x10 Bad command Unsupported command, possibly due to programming error or incorrect device population. For example, an Si4771 is mistakenly placed on a design instead of the Si4777 and and an attempt is made to configure the part for ZIF output. 0x11 Bad ARG1 0x12 Bad ARG2 0x13 Bad ARG3 0x14 Bad ARG4 0x18 Command Busy 0x20 198 Argument out of range or invalid mode, possibly due to programming error or incorrect device population. Wait for command completion, or abort tune/seek. Bad internal memory Internal memory corruption. Contact Silicon Labs. Patch CRC is incorrect. Recover by repeating the powerup sequence with correct patch. 0x30 Bad patch 0x31 Bad boot mode Mode is not supported. Recover by repeating the powerup sequence with supported mode (AM, FM). 0x40 Bad property Unsupported property, possibly due to programming error or incorrect device population. Rev. 0.3 AN645 10.2.5. Check STC Status After every command the STC (seek/tune complete) bit state should be checked to determine the state of the tune or seek command and abort the operation if desired. Start 1. Read STATUS 2. STC = 1? No 3. User Abort? Yes Yes 2. Set STCACK =1, set ATTUNE = 1 and call FM_RSQ_STATUS or AM_RSQ_STATUS 3. Set CANCEL =1 and call FM_RSQ_STATUS or AM_RSQ_STATUS 2. Wait tCTS 3. Wait 5ms No 4. Wait tSTC End 1. Read the STATUS byte. 2. If STC (seek/tune complete) is set, set STCACK = 1 to acknowledge and clear the STC bit and set ATTUNE = 1 to return RSQ metrics from tune time and call FM_RSQ_STATUS (or AM_RSQ_STATUS). Rev. 0.3 199 AN645 Example: FM_RSQ_STATUS Command Action Data Description CMD 0x32 FM_RSQ_STATUS ARG1 0x05 Return metrics from tune time, acknowledge the STC interrupt. STATUS →0x81 CTS = 1, STC = 1 RESP1 →0x00 RESP2 →0x31 SNR ready, RSSI ready, valid channel. RESP3 →0x27 Tuning frequency 0x027A6 = 101.50 MHz RESP4 →0xA6 RESP5 →0x10 Frequency offset = 16 ppm RESP6 →0x25 RSSI = 37 dBµV RESP7 →0x14 SNR = 20 dB RESP8 →0x00 RESP9 →0xFB –100 kHz channel signal strength (LASSI) 0xFB = –5 dB RESP10 →0xF4 +100 kHz channel signal strength (HASSI) 0xFB = –12 dB RESP11 →0x0B Multipath 0x0B = 11 RESP12 →0x0F Reserved, values will vary. RESP13 →0x00 0x000 = Antenna capacitance, only for tracking filter applications RESP14 →0x00 RESP15 →0xE5 ±200 kHz channel signal strength (ASSI) 0xE5 = –27 dB RESP16 →0x2A Ultrasonic noise (USN) 0x2A = 42 3. If STC is not set and the user wishes to abort the tune, set CANCEL = 1 to abort and call FM_RSQ_STATUS (or AM_RSQ_STATUS). Wait 5 ms for the tune or seek to abort and set the STC bit. 4. Wait tSTC (21–40 ms depending AM or FM modes). Refer to "8. Timing" on page 22. 200 Rev. 0.3 AN645 DOCUMENT CHANGE LIST Revision 0.1 to Revision 0.2 Removed support for STRONGDEV, and 4 MHz crystal operation. Added support for LowCut and ASSI-based VALID tune/seek check. Revision 0.2 to Revision 0.3 Updated " Property 0x2205 FM_CHBW_ASSI_MIN_MAX" on page 104. Updated " Property 0x220A FM_CHBW_ASSI200_MIN_MAX " on page 106. Updated " Command 0x32 FM_RSQ_STATUS" on page 64. Updated " Property 0x0403 FM_SOFT_MUTE_RELEASE_TIME" on page 78. Updated " Property 0x0404 FM_SOFT_MUTE_ATTACK_TIME" on page 78. Updated " Property 0x4003 FM_RDS_CONFIDENCE" on page 136. Updated " Property 0x0403 AM_SOFT_MUTE_RELEASE_TIME" on page 153. Updated " Property 0x0404 AM_SOFT_MUTE_ATTACK_TIME" on page 154. Rev. 0.3 201 AN645 CONTACT INFORMATION Silicon Laboratories Inc. 400 West Cesar Chavez Austin, TX 78701 Tel: 1+(512) 416-8500 Fax: 1+(512) 416-9669 Toll Free: 1+(877) 444-3032 Please visit the Silicon Labs Technical Support web page: https://www.silabs.com/support/pages/contacttechnicalsupport.aspx and register to submit a technical support request. Patent Notice Silicon Labs invests in research and development to help our customers differentiate in the market with innovative low-power, small size, analogintensive mixed-signal solutions. Silicon Labs' extensive patent portfolio is a testament to our unique approach and world-class engineering team. The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice. Silicon Laboratories assumes no responsibility for errors and omissions, and disclaims responsibility for any consequences resulting from the use of information included herein. Additionally, Silicon Laboratories assumes no responsibility for the functioning of undescribed features or parameters. Silicon Laboratories reserves the right to make changes without further notice. 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Other products or brandnames mentioned herein are trademarks or registered trademarks of their respective holders. 202 Rev. 0.3