Documentation/Maemo 5 Developer Guide/Using Multimedia Components/FM Transmitter API Usage
(reformat tables, wikify slightly) |
(wikify slightly) |
||
(3 intermediate revisions not shown) | |||
Line 1: | Line 1: | ||
__FORCETOC__ | __FORCETOC__ | ||
- | FM Transmitter is controlled by <code>fmtx-middleware</code> program via D-Bus API. API includes functions to enable transmitter, change transmitting frequency and station name. Please note that available frequencies may vary by sales region and FM Transmitter may be disabled in certain sales regions. Transmitter is also disabled when external devices are connected to Maemo device, excluding charger and Bluetooth devices. When FM Transmitter is enabled, fmtx-middleware will route audio automatically to the transmitter and enforce proper transmission power allowed in sales region. Fmtx-middleware will emit beeping tone when no other audio is being transmitter to comply with legislature. | + | The [[N900 FM radio transmitter|FM Transmitter]] is controlled by <code>fmtx-middleware</code> program via D-Bus API. API includes functions to enable transmitter, change transmitting frequency and station name. Please note that available frequencies may vary by sales region and FM Transmitter may be disabled in certain sales regions. Transmitter is also disabled when external devices are connected to Maemo device, excluding charger and Bluetooth devices. When FM Transmitter is enabled, fmtx-middleware will route audio automatically to the transmitter and enforce proper transmission power allowed in sales region. Fmtx-middleware will emit beeping tone when no other audio is being transmitter to comply with legislature. API documentation is in the [http://maemo.org/packages/view/fmtx-middleware-doc/ fmtx-middleware-doc] package. |
== API documentation == | == API documentation == | ||
- | + | ;Service | |
- | + | : <code>com.nokia.FMTx</code> | |
- | Interface: com.nokia.FMTx.Device | + | ;Interface |
- | Object path: /com/nokia/fmtx/default | + | : <code>com.nokia.FMTx.Device</code> |
- | </ | + | ;Object path |
- | + | : <code>/com/nokia/fmtx/default</code> | |
===Properties=== | ===Properties=== | ||
{| class="wikitable" | {| class="wikitable" | ||
- | | version | + | |+ D-Bus properties |
+ | |- | ||
+ | ! Name | ||
+ | ! Type | ||
+ | ! Flags | ||
+ | ! Description | ||
+ | |- | ||
+ | | <code>version</code> | ||
| Uint32 | | Uint32 | ||
| Read only | | Read only | ||
| Version number of <code>fmtx-middleware</code> | | Version number of <code>fmtx-middleware</code> | ||
|- | |- | ||
- | | frequency | + | | <code>frequency</code> |
| Uint32 | | Uint32 | ||
| Read/write | | Read/write | ||
| Frequency in kHz. Returns <code>DBUS_GERROR_INVALID_ARGS</code> error, if frequency is not allowed | | Frequency in kHz. Returns <code>DBUS_GERROR_INVALID_ARGS</code> error, if frequency is not allowed | ||
|- | |- | ||
- | | freq_max | + | | <code>freq_max</code> |
| Uint32 | | Uint32 | ||
| Read only | | Read only | ||
| Returns maximum allowed frequency in kHz | | Returns maximum allowed frequency in kHz | ||
|- | |- | ||
- | | freq_step | + | | <code>freq_step</code> |
| Uint32 | | Uint32 | ||
| Read only | | Read only | ||
| Returns the minimum step between frequencies in kHz | | Returns the minimum step between frequencies in kHz | ||
|- | |- | ||
- | | state | + | | <code>state</code> |
| String | | String | ||
| Read/write | | Read/write | ||
- | | Returns the state of the transmitter. States are: enabled – Transmitter is currently enabled disabled – Transmitter is currently disabled error – Internal error while initializing the transmitter, transmitter can’t be enabled. n/a – Transmitter is permanently disabled in this device. State can be set to enabled or disabled. May return <code>DBUS_GERROR_FAILED</code> if transmitter can’t be enabled | + | | Returns the state of the transmitter. States are: |
+ | * enabled – Transmitter is currently enabled | ||
+ | * disabled – Transmitter is currently disabled | ||
+ | * error – Internal error while initializing the transmitter, transmitter can’t be enabled. | ||
+ | * n/a – Transmitter is permanently disabled in this device. | ||
+ | State can be set to enabled or disabled. | ||
+ | May return <code>DBUS_GERROR_FAILED</code> if transmitter can’t be enabled | ||
|- | |- | ||
- | | startable | + | | <code>startable</code> |
| String | | String | ||
| Read only | | Read only | ||
| Returns message about can the transmitter be enabled at current time. Messages are: true Device is in offline mode Headphones are connected USB device is connected | | Returns message about can the transmitter be enabled at current time. Messages are: true Device is in offline mode Headphones are connected USB device is connected | ||
|- | |- | ||
- | | rds_ps | + | | <code>rds_ps</code> |
| String | | String | ||
| Read/write | | Read/write | ||
- | | Get/Set RDS | + | | Get/Set RDS Station name (displayed on rds capable radios). To avoid problems with some radios, use text which length is dividable by 8. Pad with spaces if necessary |
|- | |- | ||
- | | rds_text | + | | <code>rds_text</code> |
| String | | String | ||
| Read/write | | Read/write | ||
- | | Get/Set RDS text (displayed alternating with station name. Maximum length is 64 characters. Returns <code>DBUS_GERROR_INVALID_ARGS</code> is set text is too long | + | | Get/Set RDS text (displayed alternating with station name. Maximum length is 64 characters. Returns <code>DBUS_GERROR_INVALID_ARGS</code> is set if the text is too long |
|} | |} | ||
Line 59: | Line 72: | ||
{| class="wikitable" | {| class="wikitable" | ||
- | | Changed | + | |+ D-Bus signals |
+ | |- | ||
+ | ! Name | ||
+ | ! Type | ||
+ | ! Description | ||
+ | |- | ||
+ | | <code>Changed</code> | ||
| None | | None | ||
| Some fmtx property was changed | | Some fmtx property was changed | ||
|- | |- | ||
- | | Error | + | | <code>Error</code> |
| String | | String | ||
| FM transmitter was disabled by one of the following reasons: <ul><li>Device entered offline mode</li><li>USB device was connected (excluding charger)</li><li>Headphones were connected</li><li>TV-Out cable was connected</li></ul> | | FM transmitter was disabled by one of the following reasons: <ul><li>Device entered offline mode</li><li>USB device was connected (excluding charger)</li><li>Headphones were connected</li><li>TV-Out cable was connected</li></ul> | ||
|} | |} | ||
- | Properties are manipulated with <code>org.freedesktop.DBus.Properties</code> interface. For more information see D-Bus documentation. | + | Properties are manipulated with <code>org.freedesktop.DBus.Properties</code> interface. For more information see [[Documentation/Maemo 5 Developer Guide/DBus|D-Bus documentation]]. |
[[Category:Development]] | [[Category:Development]] | ||
[[Category:Documentation]] | [[Category:Documentation]] | ||
[[Category:Fremantle]] | [[Category:Fremantle]] |
Latest revision as of 13:20, 1 March 2011
The FM Transmitter is controlled by fmtx-middleware
program via D-Bus API. API includes functions to enable transmitter, change transmitting frequency and station name. Please note that available frequencies may vary by sales region and FM Transmitter may be disabled in certain sales regions. Transmitter is also disabled when external devices are connected to Maemo device, excluding charger and Bluetooth devices. When FM Transmitter is enabled, fmtx-middleware will route audio automatically to the transmitter and enforce proper transmission power allowed in sales region. Fmtx-middleware will emit beeping tone when no other audio is being transmitter to comply with legislature. API documentation is in the fmtx-middleware-doc package.
Contents |
[edit] API documentation
- Service
-
com.nokia.FMTx
- Interface
-
com.nokia.FMTx.Device
- Object path
-
/com/nokia/fmtx/default
[edit] Properties
Name | Type | Flags | Description |
---|---|---|---|
version
| Uint32 | Read only | Version number of fmtx-middleware
|
frequency
| Uint32 | Read/write | Frequency in kHz. Returns DBUS_GERROR_INVALID_ARGS error, if frequency is not allowed
|
freq_max
| Uint32 | Read only | Returns maximum allowed frequency in kHz |
freq_step
| Uint32 | Read only | Returns the minimum step between frequencies in kHz |
state
| String | Read/write | Returns the state of the transmitter. States are:
State can be set to enabled or disabled.
May return |
startable
| String | Read only | Returns message about can the transmitter be enabled at current time. Messages are: true Device is in offline mode Headphones are connected USB device is connected |
rds_ps
| String | Read/write | Get/Set RDS Station name (displayed on rds capable radios). To avoid problems with some radios, use text which length is dividable by 8. Pad with spaces if necessary |
rds_text
| String | Read/write | Get/Set RDS text (displayed alternating with station name. Maximum length is 64 characters. Returns DBUS_GERROR_INVALID_ARGS is set if the text is too long
|
[edit] Signals
Name | Type | Description |
---|---|---|
Changed
| None | Some fmtx property was changed |
Error
| String | FM transmitter was disabled by one of the following reasons:
|
Properties are manipulated with org.freedesktop.DBus.Properties
interface. For more information see D-Bus documentation.
- This page was last modified on 1 March 2011, at 13:20.
- This page has been accessed 19,822 times.