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diff --git a/dvb-spec/dvbapi/frontend.tex b/dvb-spec/dvbapi/frontend.tex deleted file mode 100644 index 9ae8a343e..000000000 --- a/dvb-spec/dvbapi/frontend.tex +++ /dev/null @@ -1,674 +0,0 @@ -\devsec{DVB Frontend API} - -The DVB frontend device controls the tuner and DVB demodulator hardware. -It can be accessed through \texttt{/dev/dvb/adapter0/frontend0}. -Data types and and ioctl definitions can be accessed by including -\texttt{linux/dvb/frontend.h} in your application. - -DVB frontends come in three varieties: DVB-S (satellite), DVB-C (cable) -and DVB-T (terrestrial). Transmission via the internet (DVB-IP) is -not yet handled by this API but a future extension is possible. -For DVB-S the frontend device also supports satellite equipment control -(SEC) via DiSEqC and V-SEC protocols. The DiSEqC (digital SEC) specification -is available from Eutelsat \texttt{http://www.eutelsat.org/}. - -Note that the DVB API may also be used for MPEG decoder-only PCI cards, -in which case there exists no frontend device. - -\devsubsec{Frontend Data Types} - -\devsubsubsec{frontend type} -\label{frontendtype} - -For historical reasons frontend types are named after the -type of modulation used in transmission. - -\begin{verbatim} -typedef enum fe_type { - FE_QPSK, /* DVB-S */ - FE_QAM, /* DVB-C */ - FE_OFDM /* DVB-T */ -} fe_type_t; -\end{verbatim} - -\devsubsubsec{frontend capabilities} -\label{frontendcaps} - -Capabilities describe what a frontend can do. Some capabilities -can only be supported for a specific frontend type. - -\begin{verbatim} -typedef enum fe_caps { - FE_IS_STUPID = 0, - FE_CAN_INVERSION_AUTO = 0x1, - FE_CAN_FEC_1_2 = 0x2, - FE_CAN_FEC_2_3 = 0x4, - FE_CAN_FEC_3_4 = 0x8, - FE_CAN_FEC_4_5 = 0x10, - FE_CAN_FEC_5_6 = 0x20, - FE_CAN_FEC_6_7 = 0x40, - FE_CAN_FEC_7_8 = 0x80, - FE_CAN_FEC_8_9 = 0x100, - FE_CAN_FEC_AUTO = 0x200, - FE_CAN_QPSK = 0x400, - FE_CAN_QAM_16 = 0x800, - FE_CAN_QAM_32 = 0x1000, - FE_CAN_QAM_64 = 0x2000, - FE_CAN_QAM_128 = 0x4000, - FE_CAN_QAM_256 = 0x8000, - FE_CAN_QAM_AUTO = 0x10000, - FE_CAN_TRANSMISSION_MODE_AUTO = 0x20000, - FE_CAN_BANDWIDTH_AUTO = 0x40000, - FE_CAN_GUARD_INTERVAL_AUTO = 0x80000, - FE_CAN_HIERARCHY_AUTO = 0x100000, - FE_CAN_MUTE_TS = 0x80000000, - FE_CAN_CLEAN_SETUP = 0x40000000 -} fe_caps_t; -\end{verbatim} - -\devsubsubsec{frontend information} -\label{frontendinfo} - -Information about the frontend ca be queried with -FE\_GET\_INFO (\ref{fegetinfo}). - -\begin{verbatim} -struct dvb_frontend_info { - char name[128]; - fe_type_t type; - uint32_t frequency_min; - uint32_t frequency_max; - uint32_t frequency_stepsize; - uint32_t frequency_tolerance; - uint32_t symbol_rate_min; - uint32_t symbol_rate_max; - uint32_t symbol_rate_tolerance; /* ppm */ - uint32_t notifier_delay; /* ms */ - fe_caps_t caps; -}; -\end{verbatim} - -\devsubsubsec{diseqc master command} -\label{diseqcmastercmd} - -A message sent from the frontend to DiSEqC capable equipment. - -\begin{verbatim} -struct dvb_diseqc_master_cmd { - uint8_t msg [6]; /* { framing, address, command, data[3] } */ - uint8_t msg_len; /* valid values are 3...6 */ -}; -\end{verbatim} - -\devsubsubsec{diseqc slave reply} -\label{diseqcslavereply} - -A reply to the frontend from DiSEqC 2.0 capable equipment. - -\begin{verbatim} -struct dvb_diseqc_slave_reply { - uint8_t msg [4]; /* { framing, data [3] } */ - uint8_t msg_len; /* valid values are 0...4, 0 means no msg */ - int timeout; /* return from ioctl after timeout ms with */ -}; /* errorcode when no message was received */ -\end{verbatim} - -\devsubsubsec{SEC voltage} -\label{secvoltage} - -The voltage is usually used with non-DiSEqC capable LNBs to -switch the polarzation (horizontal/vertical). -When using DiSEqC epuipment this voltage has to be switched consistently -to the DiSEqC commands as described in the DiSEqC spec. - -\begin{verbatim} -typedef enum fe_sec_voltage { - SEC_VOLTAGE_13, - SEC_VOLTAGE_18 -} fe_sec_voltage_t; -\end{verbatim} - -\devsubsubsec{SEC continuous tone} -\label{sectone} - -The continous 22KHz tone is usually used with non-DiSEqC capable LNBs to -switch the high/low band of a dual-band LNB. -When using DiSEqC epuipment this voltage has to be switched consistently -to the DiSEqC commands as described in the DiSEqC spec. - -\begin{verbatim} -typedef enum fe_sec_tone_mode { - SEC_TONE_ON, - SEC_TONE_OFF -} fe_sec_tone_mode_t; -\end{verbatim} - -\devsubsubsec{SEC tone burst} -\label{sectoneburst} - -The 22KHz tone burst is usually used with non-DiSEqC capable -switches to select between two connected LNBs/satellites. -When using DiSEqC epuipment this voltage has to be switched consistently -to the DiSEqC commands as described in the DiSEqC spec. - -\begin{verbatim} -typedef enum fe_sec_mini_cmd { - SEC_MINI_A, - SEC_MINI_B -} fe_sec_mini_cmd_t; -\end{verbatim} - - -\devsubsubsec{frontend status} -\label{frontendstatus} - -Several functions of the frontend device use the fe\_status data -type defined by -\begin{verbatim} -typedef enum fe_status { - FE_HAS_SIGNAL = 0x01, /* found something above the noise level */ - FE_HAS_CARRIER = 0x02, /* found a DVB signal */ - FE_HAS_VITERBI = 0x04, /* FEC is stable */ - FE_HAS_SYNC = 0x08, /* found sync bytes */ - FE_HAS_LOCK = 0x10, /* everything's working... */ - FE_TIMEDOUT = 0x20, /* no lock within the last ~2 seconds */ - FE_REINIT = 0x40 /* frontend was reinitialized, */ -} fe_status_t; /* application is recommned to reset */ -\end{verbatim} -to indicate the current state and/or state changes of -the frontend hardware. - - -\devsubsubsec{frontend parameters} -\label{frontendparameters} - -The kind of parameters passed to the frontend device for tuning -depend on the kind of hardware you are using. -All kinds of parameters are combined as a union in the -FrontendParameters structure: -\begin{verbatim} -struct dvb_frontend_parameters { - uint32_t frequency; /* (absolute) frequency in Hz for QAM/OFDM */ - /* intermediate frequency in kHz for QPSK */ - fe_spectral_inversion_t inversion; - union { - struct dvb_qpsk_parameters qpsk; - struct dvb_qam_parameters qam; - struct dvb_ofdm_parameters ofdm; - } u; -}; -\end{verbatim} - -For satellite QPSK frontends you have to use the \verb|QPSKParameters| member -defined by -\begin{verbatim} -struct dvb_qpsk_parameters { - uint32_t symbol_rate; /* symbol rate in Symbols per second */ - fe_code_rate_t fec_inner; /* forward error correction (see above) */ -}; -\end{verbatim} -for cable QAM frontend you use the \verb|QAMParameters| structure -\begin{verbatim} -struct dvb_qam_parameters { - uint32_t symbol_rate; /* symbol rate in Symbols per second */ - fe_code_rate_t fec_inner; /* forward error correction (see above) */ - fe_modulation_t modulation; /* modulation type (see above) */ -}; -\end{verbatim} -DVB-T frontends are supported by the \verb|OFDMParamters| structure -\begin{verbatim} -struct dvb_ofdm_parameters { - fe_bandwidth_t bandwidth; - fe_code_rate_t code_rate_HP; /* high priority stream code rate */ - fe_code_rate_t code_rate_LP; /* low priority stream code rate */ - fe_modulation_t constellation; /* modulation type (see above) */ - fe_transmit_mode_t transmission_mode; - fe_guard_interval_t guard_interval; - fe_hierarchy_t hierarchy_information; -}; -\end{verbatim} - -In the case of QPSK frontends the \verb|Frequency| field specifies the -intermediate frequency, i.e. the offset which is effectively added to the -local oscillator frequency (LOF) of the LNB. -The intermediate frequency has to be specified in units of kHz. -For QAM and OFDM frontends the Frequency specifies the absolute frequency -and is given in Hz. - -The Inversion field can take one of these values: -\begin{verbatim} -typedef enum fe_spectral_inversion { - INVERSION_OFF, - INVERSION_ON, - INVERSION_AUTO -} fe_spectral_inversion_t; -\end{verbatim} -It indicates if spectral inversion should be presumed or not. -In the automatic setting (\verb|INVERSION_AUTO|) the hardware will -try to figure out the correct setting by itself. - -\noindent -The possible values for the \verb|FEC_inner| field are -\begin{verbatim} -typedef enum fe_code_rate { - FEC_NONE = 0, - FEC_1_2, - FEC_2_3, - FEC_3_4, - FEC_4_5, - FEC_5_6, - FEC_6_7, - FEC_7_8, - FEC_8_9, - FEC_AUTO -} fe_code_rate_t; -\end{verbatim} -which correspond to error correction rates of 1/2, 2/3, etc., -no error correction or auto detection. - -\noindent -For cable and terrestrial frontends (QAM and OFDM) one also has to -specify the quadrature modulation mode which can be one of the following: -\begin{verbatim} -typedef enum fe_modulation { - QPSK, - QAM_16, - QAM_32, - QAM_64, - QAM_128, - QAM_256, - QAM_AUTO -} fe_modulation_t; -\end{verbatim} - -Finally, there are several more parameters for OFDM: -\begin{verbatim} -typedef enum fe_transmit_mode { - TRANSMISSION_MODE_2K, - TRANSMISSION_MODE_8K, - TRANSMISSION_MODE_AUTO -} fe_transmit_mode_t; -\end{verbatim} - -\begin{verbatim} -typedef enum fe_bandwidth { - BANDWIDTH_8_MHZ, - BANDWIDTH_7_MHZ, - BANDWIDTH_6_MHZ, - BANDWIDTH_AUTO -} fe_bandwidth_t; -\end{verbatim} - -\begin{verbatim} -typedef enum fe_guard_interval { - GUARD_INTERVAL_1_32, - GUARD_INTERVAL_1_16, - GUARD_INTERVAL_1_8, - GUARD_INTERVAL_1_4, - GUARD_INTERVAL_AUTO -} fe_guard_interval_t; -\end{verbatim} - -\begin{verbatim} -typedef enum fe_hierarchy { - HIERARCHY_NONE, - HIERARCHY_1, - HIERARCHY_2, - HIERARCHY_4, - HIERARCHY_AUTO -} fe_hierarchy_t; -\end{verbatim} - - -\devsubsubsec{frontend events} -\label{frontendevents} - -\begin{verbatim} -struct dvb_frontend_event { - fe_status_t status; - struct dvb_frontend_parameters parameters; -}; -\end{verbatim} - -\clearpage - - -\devsubsec{Frontend Function Calls} - -\function{open()}{ - int open(const char *deviceName, int flags);}{ - This system call opens a named frontend device (/dev/dvb/adapter0/frontend0) - for subsequent use. Usually the first thing to do after a successful open - is to find out the frontend type with FE\_GET\_INFO. - - The device can be opened in read-only mode, which only allows - monitoring of device status and statistics, or read/write mode, which allows - any kind of use (e.g. performing tuning operations.) - - In a system with multiple front-ends, it is usually the case that multiple - devices cannot be open in read/write mode simultaneously. As long as a - front-end device is opened in read/write mode, other open() calls in - read/write mode will either fail or block, depending on whether - non-blocking or blocking mode was specified. - A front-end device opened in blocking mode can later be put into non-blocking - mode (and vice versa) using the F\_SETFL command of the fcntl system call. - This is a standard system call, documented in the Linux manual page for fcntl. - When an open() call has succeeded, the device will be ready for use in the - specified mode. This implies that the corresponding hardware is powered up, - and that other front-ends may have been powered down to make that possible. - - }{ - const char *deviceName & Name of specific video device.\\ - int flags & A bit-wise OR of the following flags:\\ - & \hspace{1em} O\_RDONLY read-only access\\ - & \hspace{1em} O\_RDWR read/write access\\ - & \hspace{1em} O\_NONBLOCK open in non-blocking mode \\ - & \hspace{1em} (blocking mode is the default)\\ - }{ - ENODEV & Device driver not loaded/available.\\ - EINTERNAL & Internal error.\\ - EBUSY & Device or resource busy.\\ - EINVAL & Invalid argument.\\ -} - -\function{close()}{ - int close(int fd);}{ - This system call closes a previously opened front-end device. - After closing a front-end device, its corresponding hardware might be - powered down automatically. - }{ - int fd & File descriptor returned by a previous call to open().\\ - }{ - EBADF & fd is not a valid open file descriptor.\\ -} - -\ifunction{FE\_READ\_STATUS}{ - int ioctl(int fd, int request = FE\_READ\_STATUS, fe\_status\_t *status);}{ - This ioctl call returns status information about the front-end. - This call only requires read-only access to the device. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_READ\_STATUS for this command.\\ - struct fe\_status\_t *status & Points to the location where the front-end - status word is to be stored. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& status points to invalid address.\\ -} - -\ifunction{FE\_READ\_BER}{ - int ioctl(int fd, int request = FE\_READ\_BER, uint32\_t *ber);}{ - This ioctl call returns the bit error rate for the signal currently - received/demodulated by the front-end. For this command, read-only access - to the device is sufficient. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_READ\_BER for this command.\\ - uint32\_t *ber & The bit error rate is stored into *ber.\\ - }{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& ber points to invalid address.\\ - ENOSIGNAL& There is no signal, thus no meaningful bit error - rate. Also returned if the front-end is not turned on.\\ - ENOSYS& Function not available for this device. -} - -\ifunction{FE\_READ\_SNR}{ - int ioctl(int fd, int request = FE\_READ\_SNR, int16\_t *snr);}{ - This ioctl call returns the signal-to-noise ratio for the signal currently - received by the front-end. For this command, read-only access to the device - is sufficient. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_READ\_SNR for this command.\\ - int16\_t *snr& The signal-to-noise ratio is stored into *snr.\\ -}{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& snr points to invalid address.\\ - ENOSIGNAL& There is no signal, thus no meaningful signal - strength value. Also returned if front-end is not turned on.\\ - ENOSYS& Function not available for this device. -} - -\ifunction{FE\_READ\_SIGNAL\_STRENGTH}{ - int ioctl( int fd, int request = FE\_READ\_SIGNAL\_STRENGTH, int16\_t *strength); -}{ -This ioctl call returns the signal strength value for the signal currently -received by the front-end. For this command, read-only access to the device -is sufficient. -}{ -int fd & File descriptor returned by a previous call to open().\\ -int request & Equals FE\_READ\_SIGNAL\_STRENGTH for this command.\\ -int16\_t *strength & The signal strength value is stored into *strength.\\ -}{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& status points to invalid address.\\ - ENOSIGNAL& There is no signal, thus no meaningful signal - strength value. Also returned if front-end is not turned on.\\ - ENOSYS& Function not available for this device. -} - -\ifunction{FE\_READ\_UNCORRECTED\_BLOCKS}{ - int ioctl( int fd, int request = FE\_READ\_UNCORRECTED\_BLOCKS, uint32\_t *ublocks); }{ - This ioctl call returns the number of uncorrected blocks detected by - the device driver during its lifetime. - For meaningful measurements, the increment in - block count during a specific time interval should be calculated. - For this command, read-only access to the device is sufficient.\\ - Note that the counter will wrap to zero after its maximum count has - been reached. -}{ -int fd & File descriptor returned by a previous call to open().\\ -int request & Equals FE\_READ\_UNCORRECTED\_BLOCKS for this command.\\ -uint32\_t *ublocks & The total number of uncorrected blocks seen -by the driver so far. -}{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& ublocks points to invalid address.\\ - ENOSYS& Function not available for this device. -} - - -\ifunction{FE\_SET\_FRONTEND}{ - int ioctl(int fd, int request = FE\_SET\_FRONTEND, struct dvb\_frontend\_parameters *p);}{ - This ioctl call starts a tuning operation using specified parameters. - The result of this call will be successful if the parameters were valid and - the tuning could be initiated. - The result of the tuning operation in itself, however, will arrive - asynchronously as an event (see documentation for FE\_GET\_EVENT - and FrontendEvent.) - If a new FE\_SET\_FRONTEND operation is initiated before the previous - one was completed, - the previous operation will be aborted in favor of the new one. - This command requires read/write access to the device. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_SET\_FRONTEND for this command.\\ - struct dvb\_frontend\_parameters *p& Points to parameters for tuning operation.\\ - }{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& p points to invalid address.\\ - EINVAL& Maximum supported symbol rate reached.\\ -} - -\ifunction{FE\_GET\_FRONTEND}{ - int ioctl(int fd, int request = FE\_GET\_FRONTEND, struct dvb\_frontend\_parameters *p);}{ - This ioctl call queries the currently effective frontend parameters. - For this command, read-only access to the device is sufficient. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_SET\_FRONTEND for this command.\\ - struct dvb\_frontend\_parameters *p& Points to parameters for tuning operation.\\ - }{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& p points to invalid address.\\ - EINVAL& Maximum supported symbol rate reached.\\ -} - -\ifunction{FE\_GET\_EVENT}{ - int ioctl(int fd, int request = QPSK\_GET\_EVENT, struct dvb\_frontend\_event *ev);}{ - This ioctl call returns a frontend event if available. If an event - is not available, the behavior depends on whether the device is in blocking - or non-blocking mode. In the latter case, the call fails immediately with - errno set to EWOULDBLOCK. In the former case, the call blocks until an event - becomes available.\\ - The standard Linux poll() and/or select() system calls can be used with the - device file descriptor to watch for new events. For select(), the file - descriptor should be included in the exceptfds argument, and for poll(), - POLLPRI should be specified as the wake-up condition. - Since the event queue allocated is rather small (room for 8 events), the queue - must be serviced regularly to avoid overflow. If an overflow happens, the - oldest event is discarded from the queue, and an error (EOVERFLOW) occurs - the next time the queue is read. After reporting the error condition in this - fashion, subsequent FE\_GET\_EVENT calls will return events from the queue as - usual.\\ - For the sake of implementation simplicity, this command requires read/write - access to the device. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_GET\_EVENT for this command.\\ - struct dvb\_frontend\_event *ev & Points to the location where the event,\\ - & if any, is to be stored. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& ev points to invalid address.\\ - EWOULDBLOCK & There is no event pending, and the device is in - non-blocking mode.\\ - EOVERFLOW &\\ -& Overflow in event queue - one or more events were lost.\\ -} - -\ifunction{FE\_GET\_INFO}{ -\label{fegetinfo} - int ioctl(int fd, int request = FE\_GET\_INFO, struct dvb\_frontend\_info *info);}{ - This ioctl call returns information about the front-end. - This call only requires read-only access to the device. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_GET\_INFO for this command.\\ - struct dvb\_frontend\_info *info & Points to the location where the front-end - information is to be stored. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EFAULT& info points to invalid address.\\ -} - -\ifunction{FE\_DISEQC\_RESET\_OVERLOAD}{ - int ioctl(int fd, int request = FE\_DISEQC\_RESET\_OVERLOAD);}{ - If the bus has been automatically powered off due to power overload, this - ioctl call restores the power to the bus. The call requires read/write - access to the device. - This call has no effect if the device is manually powered off. - Not all DVB adapters support this ioctl. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_DISEQC\_RESET\_OVERLOAD for this command.\\ - }{ - EBADF & fd is not a valid file descriptor.\\ - EPERM & Permission denied (needs read/write access).\\ - EINTERNAL & Internal error in the device driver.\\ -} - - -\ifunction{FE\_DISEQC\_SEND\_MASTER\_CMD}{ -int ioctl(int fd, int request = FE\_DISEQC\_SEND\_MASTER\_CMD, struct dvb\_diseqc\_master\_cmd *cmd);}{ - This ioctl call is used to send a a DiSEqC command.\\ - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_DISEQC\_SEND\_MASTER\_CMD for this command.\\ - struct dvb\_diseqc\_master\_cmd *cmd & Pointer to the command to be transmitted.\\ - }{ - EBADF & fd is not a valid file descriptor.\\ - EFAULT & Seq points to an invalid address.\\ - EINVAL & The data structure referred to by seq is invalid in some way.\\ - EPERM & Permission denied (needs read/write access).\\ - EINTERNAL & Internal error in the device driver.\\ -} - -\ifunction{FE\_DISEQC\_RECV\_SLAVE\_REPLY}{ -int ioctl(int fd, int request = FE\_DISEQC\_RECV\_SLAVE\_REPLY, struct dvb\_diseqc\_slave\_reply *reply);}{ -This ioctl call is used to receive reply to a DiSEqC 2.0 command.\\ - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_DISEQC\_RECV\_SLAVE\_REPLY for this command.\\ - struct dvb\_diseqc\_slave\_reply *reply & Pointer to the command to be received.\\ - }{ - EBADF & fd is not a valid file descriptor.\\ - EFAULT & Seq points to an invalid address.\\ - EINVAL & The data structure referred to by seq is invalid in some way.\\ - EPERM & Permission denied (needs read/write access).\\ - EINTERNAL & Internal error in the device driver.\\ -} - -\ifunction{FE\_DISEQC\_SEND\_BURST}{ -int ioctl(int fd, int request = FE\_DISEQC\_SEND\_BURST, fe\_sec\_mini\_cmd\_t burst);}{ -This ioctl call is used to send a 22KHz tone burst.\\ - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals FE\_DISEQC\_SEND\_BURST for this command.\\ - fe\_sec\_mini\_cmd\_t burst & burst A or B.\\ - }{ - EBADF & fd is not a valid file descriptor.\\ - EFAULT & Seq points to an invalid address.\\ - EINVAL & The data structure referred to by seq is invalid in some way.\\ - EPERM & Permission denied (needs read/write access).\\ - EINTERNAL & Internal error in the device driver.\\ -} - - -\ifunction{FE\_SET\_TONE}{ -int ioctl(int fd, int request = FE\_SET\_TONE, fe\_sec\_tone\_mode\_t tone);}{ -This call is used to set the generation of the continuous 22kHz tone. -This call requires read/write permissions. -}{ -int fd & File descriptor returned by a previous call to open().\\ -int request & Equals FE\_SET\_TONE for this command.\\ -fe\_sec\_tone\_mode\_t tone & The requested tone generation mode (on/off).\\ -}{ -ENODEV & Device driver not loaded/available.\\ -EBUSY & Device or resource busy.\\ -EINVAL & Invalid argument.\\ -EPERM & File not opened with read permissions.\\ -EINTERNAL & Internal error in the device driver.\\ -} - - -\ifunction{FE\_SET\_VOLTAGE}{ -int ioctl(int fd, int request = FE\_SET\_VOLTAGE, fe\_sec\_voltage\_t voltage);}{ -This call is used to set the bus voltage. -This call requires read/write permissions. -}{ -int fd & File descriptor returned by a previous call to open().\\ -int request & Equals FE\_SET\_VOLTAGE for this command.\\ -fe\_sec\_voltage\_t voltage & The requested bus voltage.\\ -}{ -ENODEV & Device driver not loaded/available.\\ -EBUSY & Device or resource busy.\\ -EINVAL & Invalid argument.\\ -EPERM & File not opened with read permissions.\\ -EINTERNAL & Internal error in the device driver.\\ -} - -\ifunction{FE\_ENABLE\_HIGH\_LNB\_VOLTAGE}{ -int ioctl(int fd, int request = FE\_ENABLE\_HIGH\_LNB\_VOLTAGE, int high);}{ -If high != 0 enables slightly higher voltages instead of 13/18V -(to compensate for long cables). -This call requires read/write permissions. -Not all DVB adapters support this ioctl. -}{ -int fd & File descriptor returned by a previous call to open().\\ -int request & Equals FE\_SET\_VOLTAGE for this command.\\ -int high & The requested bus voltage.\\ -}{ -ENODEV & Device driver not loaded/available.\\ -EBUSY & Device or resource busy.\\ -EINVAL & Invalid argument.\\ -EPERM & File not opened with read permissions.\\ -EINTERNAL & Internal error in the device driver.\\ -} - - -%%% Local Variables: -%%% mode: latex -%%% TeX-master: "dvbapi" -%%% End: |