Gen3 UNISHAPE Firmware Application Note P-VIP® Lamp Systems Kernel DB09 Application Note UNISHAPE – Universal Shaped Light Waveform Table of Contents 1. 2. 3. Introduction ......................................................................................................................................2 Kernel DB09 features ......................................................................................................................2 Basic driver operation ......................................................................................................................3 3.1 Lamp Starting Sequence (transition from idle to run mode)........................................................4 3.2 Error Handling .............................................................................................................................6 3.3 Lamp power control .....................................................................................................................6 4. Synchronization ...............................................................................................................................7 5. UNISHAPE waveform definition ......................................................................................................7 5.1 Segment definition table ..............................................................................................................7 5.2 Waveform composition ................................................................................................................8 5.3 Segment duration ........................................................................................................................8 5.4 Segment height ...........................................................................................................................8 5.5 Segment properties .....................................................................................................................8 6. Uploading new waveforms to the lamp driver..................................................................................9 6.1 Programming new waveforms to non-volatile EEPROM.............................................................9 6.2 Uploading new waveforms on-the-fly to SRAM...........................................................................9 7. Selecting between Waveforms ........................................................................................................9 7.1 Uploading new waveform data ....................................................................................................9 7.2 Selecting between stored waveforms by UART commands .......................................................9 7.3 Selecting between stored waveforms by the SCI on-time...........................................................9 8. Memory Map ..................................................................................................................................10 9. Safety features...............................................................................................................................12 10. Guidelines for Creating Waveforms ..........................................................................................12 10.1 Plateau levels ........................................................................................................................12 10.2 Lamp maintenance pulses with commutations .....................................................................12 10.3 Low pulses ............................................................................................................................12 11. Dynamic Dimming .....................................................................................................................12 12. Specification ..............................................................................................................................12 12.1 Minimum SCI frequency........................................................................................................12 12.2 Segment height limitations ....................................................................................................12 12.3 Segment duration limits.........................................................................................................13 12.4 Changing the waveform ........................................................................................................13 13. Kernel revision history ...............................................................................................................13 2007-03-19 Page 1 of 13 Gen3 UNISHAPE Firmware Application Note Kernel DB09 P-VIP® Lamp Systems 1. Introduction UNISHAPE can be used with several lamp types and wattages, and has no adverse effect on lamp life. Depending on the particular projection system design, Osram's UNISHAPE technology can increase the overall system efficiency. This allows the use of lower lamp wattages to produce performance similar to that of non-UNISHAPE systems. Osram´s lamp drivers with UNISHAPE firmware store a complete light waveform. With UNISHAPE one and the same lamp driver can be programmed with all existing lamp operation modes. The UNISHAPE software enables complex light curves with significant cost and quality advantages: • LowPulses down to 25% light level. LowPulses can increase the colour depth by two additional bits. The colour quality (resolution, linearity) is even better than that of a 7-segment DVE colour wheel system. Manufacturers can therefore save the extra cost for a 7-segment colour wheel. • VariablePlateau values for each segment. This enables loss-free colour adjustment. The UNISHAPE colour adjustment works without light losses because it is achieved by modulation of the light source. Up to 40% more screen lumens are possible compared to nonUNISHAPE systems. Switching between different waveforms enables brilliant colours in video mode and greatest possible brightness in data mode with the same projector. This application note describes the DB09 UNISHAPE software kernel. This lamp driver can be controlled in two ways: 1. The conventional driving mode 2. The UART mode UNISHAPE operation is possible with both ways. The following paragraphs describe the conventional mode in detail. The UART mode is only described control briefly, as there is a dedicated application note for the UART protocol. The DB09 kernel uses the standardised UART protocol, please refer to “Standardised UART protocol, Revision 1.4” from 2005-1024. 2. Kernel DB09 features • Create arbitrary light waveforms! • Select between multiple waveforms (240 byte waveform memory) • Instant PLL Synchronisation • Dynamic Dimming for contrast enhancement • Standardised UART communication • LOFS overshoot reduction improves colour linearity • EEPROM firmware update offers maximum flexibility 2007-03-19 Page 2 of 13 Gen3 UNISHAPE Firmware Application Note Kernel DB09 P-VIP® Lamp Systems 3. Basic driver operation This chapter describes how to apply control signals to the SCI interface und how the ballast will react. Furthermore, it describes the basic workflow of lamp start and stop and the related response to that. Basic requirement to all mentioned functions and timings is a stable supply voltage within the specified range of the ballast. The input voltage range is specified in the lamp driver specification. After powering up the driver the internal auxiliary supply will start up and the control logic will be reset and booted. This typically need a processing time of 100ms. Putting the driver into “Idle Mode” is a necessary condition to process signals from the SCI. For a lamp start it is always necessary to apply a valid SCI signal. This is a basic requirement to start and to operate a lamp. UART communication can be opened in idle mode, too. A valid SCI ON signal can be either a static ON or a square wave signal within a specified frequency range. Please refer to lamp driver specification for detailed information about valid SCI square wave timing. Basically two different ways to switch on and off the lamp can be distinguished: 1. Non UART mode: In conventional driving mode (non UART) lamp start and stop process only depend on SCI signal. Refer to the bold signal path in the state diagram below. 2. UART mode: If the lamp driver was put into UART mode, lamp start and stop process can be optionally controlled via UART. UART mode can be entered at any time in IDLE mode or in RUN mode. Please note again: For lamp start and lamp operation it is always mandatory to apply a valid SCI signal. 2007-03-19 Page 3 of 13 Gen3 UNISHAPE Firmware Application Note P-VIP® Lamp Systems Kernel DB09 Once UART mode has been entered it can be restored in two ways. First possibility is to recycle power and start the driver again from OFF state. Secondly, UART communication can be opened and a RESET command can be send to reset all volatile settings in the control unit of the driver. After entering RUN mode the lamp driver will start a state machine to perform a lamp start. First the lamp driver triggers the ignition sequence (high voltage). After successful ignition the driver switches to the preheating sequence where the lamp heats up. The preheating sequence is followed by normal lamp operation (low frequency operation). The lamp driver remains in normal operation until the lamp is switched off (STOP mode via UART command or IDLE mode by restoring the SCI signal). 3.1 Lamp Starting Sequence (transition from idle to run mode) Action Lamp burn conditition Flag indication uncertain Lamp Lit Flag Lamp start failed Preheating SCI hold on time min. 100ms Ignition (HV) SCI start trigger min. 20ms SCI ON IDLE MODE RUN MODE SCI OFF Boottime min. 100ms DC Supply on 0 2007-03-19 1 2 3 4 5 HV generation terminated 6 7 8 Lamp Lit flag indication stable 9 10 time/sec. Page 4 of 13 Gen3 UNISHAPE Firmware Application Note P-VIP® Lamp Systems Kernel DB09 The lamp normal operation status (low frequency operation) will be indicated via the Lamp Lit signal to the projector. This is only possible if the driver was not set into UART mode before. Thus is because the Lamp Lit indication line at the SCI interface is multiplexed with the UART TxD line. In case of UART mode has been entered, the Lamp Lit line is only controlled by UART and is no longer an indicator for a successful lamp start. In UART mode the status of lamp operation can be only read via UART communication. To read the condition a status query has to be performed and the “Lamp On” Flag has to be checked. This Flag emulate the hardware Lamp Lit indicator. In case of non UART mode and successful lamp start the Lamp Lit indicator will be set after 4s. The diagram below describes how to retry a lamp start if the first start sequence was not successful and a lamp fails to ignite. To activate another restart attempt the SCI ON signal has to be recycled. After switching off (either STOP mode or idle mode) the lamp driver waits for a certain time in order to cool down the lamp and thus prepare the system for a successful restart. A typical minimum restart * blocking time is 15 sec ( ). Restart Sequence (repetetive start cycles) Action Lamp start failed Flag indication Lamp burn conditition Lamp Lit Flag Preheating Ignition (HV) 1st start trial 2st start trial 3st start trial RUN SCI ON IDLE Restart time min. 15sec SCI OFF Boottime min. 100ms DC Supply on 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 time/sec. During the restart blocking timer is running the driver will not start the lamp even if SCI ON is applied. In UART mode the restart can be performed via UART commands. In this case a SCI ON in the drawing corresponds to a LampON command and a SCI OFF in the drawing corresponds to a LampOFF command but keep in mind that the SCI line needs to stay high ( SCI ON) to restart the driver via UART. * ( ) Values are parameterized in the system configuration. Please refer to the system specification for more details. 2007-03-19 Page 5 of 13 Gen3 UNISHAPE Firmware Application Note Kernel DB09 P-VIP® Lamp Systems Please refer to the application note “Standardized UART Protocol” to find detailed information how to use the UART command: UARTenable, Query Status, LampON, Reset and LampOFF. 3.2 Error Handling In case of abnormal operating conditions or lamp start failure (e.g. over temperature, End-of-life-voltage reached, short circuit) the driver is automatically switched off and the related error status will be stored in the driver and can be read out via UART communication. In non UART mode the lamp driver is set to idle mode and the Lamp Lit signal is cleared to indicate that the lamp operation was stopped. To restart the ballast again it is necessary to recycle the SCI signal (SCI OFF SCI ON). This will reset the error status in non UART mode. If an error occurred in non UART mode it is possible to enable UART communication afterwards and to read out the error status. To restart the driver has to be handled like in the UART mode description below. In this case the SCI needs to stay high to keep the error information present. In case of UART mode has been entered, the driver is set to STOP mode and the error status can be read via UART communication. To restart the ballast again it is necessary to send first Lamp OFF command followed by a Lamp ON command. This will reset the error status in UART mode. As long as the error status is not <no_error_occurred> the driver cannot put into RUN mode again. In UART mode the error status is not reset by switching the SCI signal off. Please refer to the application note “Standardized UART Protocol” to find detailed information how to use the UART commands: Read Error Status. 3.3 Lamp power control The lamp driver is able to operate the lamp at different power levels. In non UART mode the user can select between two different power levels (normal power and eco power) by switching the ECO mode input pin at the SCI interface. The ECO mode can be switched at any time after the driver was put into RUN mode. The lower power level of ECO mode is predefined for the related lamp type and can not be changed. It is not recommended to switch ECO mode during the lamp starting process. In case of UART mode has been entered, lamp power control is only possible via UART communication. This is because the ECO mode input line at the SCI interface is multiplexed with the UART RxD line. By means of the Set Gain command it is possible to set a power level within a certain dimming range. The lamp power will be scaled with a certain percentage from the nominal power. The power range is predefined for the corresponding lamp type and can not be changed. The typical dimming resolution is 1% (*) from nominal lamp power. This feature can be used for Dynamic Dimming where the power level has to be adjusted according to the video information. Please refer to the application note “Standardized UART Protocol” to find detailed information how to use the UART command: SetGain. 2007-03-19 Page 6 of 13 Gen3 UNISHAPE Firmware Application Note P-VIP® Lamp Systems Kernel DB09 4. Synchronization The SCI input is used not only for switching on and off the lamp, but also for synchronization. UNISHAPE is easy to synchronize! It avoids complex SCI synchronization patterns because it only uses the SCI pulse as a clock cycle. The start of the waveform is synchronized with the rising edge of the SCI signal. The delay time tdelay between SCI signal and waveform is constant 190µs. All waveform segments are scaled linearly in order to fit the whole waveform into the SCI period. The synchronization routine itself is a digital PLL. It reacts to rising SCI current edges. To avoid any artefacts constant and continuous SCI timing without jitter is mandatory. If the SCI input is receiving a static ON signal the lamp driver operates the lamp in free running mode. The internal frequency is defined in the waveform information. 5. UNISHAPE waveform definition The complete waveform information is stored in the memory of the lamp driver. The waveform itself consists of the segment definition table and the sequence composition. Each rising SCI edge triggers a new start of the waveform. The term SCI signal refers to the current, not the voltage. This is because the optocouplers of the 5pin interface can only detect currents. It’s recommendable to use a simple square wave signal with a dutycycle of 50%, if you just have one waveform. 5.1 Segment definition table Segment type hfactor dfactor properties 0 100 60 0b00000000 1 134 13 0b00001001 2 50 8 0b00000000 … … … … … … … … 2007-03-19 Page 7 of 13 Gen3 UNISHAPE Firmware Application Note P-VIP® Lamp Systems Kernel DB09 5.2 Waveform composition The waveform is a string of segments: Segment number 0 1 2 segment type 5 3 13 … … The segments theirselves are defined as described in section 5.1. 5.3 Segment duration The periodic length of the SCI signal is measured by the lamp driver. All segment widths are scaled linearly so that the whole waveform fits into the SCI period: Dwaveform = ∑d factor waveform t segment = d factor Dwaveform ⋅ 1 f SCI The parameter dfactor is stored in the appropriate EEPROM cells. The range of the dfactor is from 0 to 255. 5.4 Segment height The parameter hfactor sets the height of each segment. The pulse height values 0..255 equal multiplication factors between 0 and 2. The segment current is calculated as follows: I segment = I mean ⋅ 5.5 h factor 27 Segment properties The segment properties are set by the property byte of each segment type. The individual properties are stored in the memory, like all other segment parameters, too. The bits of this byte have the following meaning: • Bit 0 - Current commutation at the end of the segment This bit defines if the segment is followed by a commutation (bit is set) or not (bit is 0). • Bit 1 - Reserved • Bit 2 - Reserved • Bit 3 - Overshoot reduction at the end of segment If this bit is set the lamp driver changes the current smoothly in order to avoid ripple in light output. • Bit 4 - Reserved • Bit 5 - Power synchronization This bit controls where a new power level will be activated. For Dynamic Dimming it is important to synchronize the power shifts with the video frames. • Bit 6 - Lamp voltage measurement This bit defines, wether a lamp voltage measurement is to be performed during the segment. Because the lamp voltage depends to a degree on the lamp current it is recommendable to place a voltage measurement in each full plateau segment. The software calculates the average lamp voltage. • Bit 7 - Reserved 2007-03-19 Page 8 of 13 Gen3 UNISHAPE Firmware Application Note P-VIP® Lamp Systems Kernel DB09 6. Uploading new waveforms to the lamp driver The lamp driver comes pre-programmed with a standard RGBRGB waveform from the factory. The user can reprogram this standard waveform with his own one. Furthermore it is possible to program more than just one waveform into the lamp driver. At least one valid waveform must be programmed in the lamp driver, otherwise it will not work properly. The maximum number of waveforms is limited by the total waveform memory. For programming new waveforms UART communication is necessary. 6.1 Programming new waveforms to non-volatile EEPROM The programming of waveforms to EEPROM can be done both before assembly of the lamp driver and later during runtime. The reprogramming of a waveform takes approximately 2 seconds and is limited to 50.000 rewriting cycles. OSRAM provides hardware and software tools for reprogramming the lamp driver before assembly. If the customer integrates the waveform data into the memory of the display unit’s system processor which is connected via UART to the lamp driver, it is also possible to reprogram the EEPROM during setup of the MD-TV/Projector System. 6.2 Uploading new waveforms on-the-fly to SRAM The SRAM is the lamp driver’s working memory. As the SRAM is volatile the EEPROM waveforms are copied on every power-up to the SRAM. The lamp driver executes the waveform from SRAM. This waveform data can be changed on-the-fly without any rewrite cycle restrictions. The upload can be performed even during lamp operation. For this purpose commands are available in the UART command set of the lamp driver to write data into dedicated locations of the SRAM. 7. Selecting between Waveforms There are three possible ways to select between waveforms: 1. Uploading new waveform data to SRAM 2. Selecting between stored waveforms by UART commands 3. Selecting between stored waveforms by the SCI on-time. 7.1 Uploading new waveform data A change of waveform can be achieved by simply overwriting the waveform in SRAM as it is described in section 6.2. 7.2 Selecting between stored waveforms by UART commands There are special UART commands for switching between stored waveforms. Please refer to the UART Protocol application note. 7.3 Selecting between stored waveforms by the SCI on-time. The lamp driver scans the on-time of the SCI signal. If this time is within the white area the lamp driver switches to the waveform number shown in the diagram. If the on-time is within the shaded area no change is done. This hysteresis is implemented in order to prevent the lamp driver from switching back and forth. 0 1 2 3 . . . ... 0 512 2007-03-19 1024 1536 2048 2560 3072 SCI on-time in µs Page 9 of 13 Gen3 UNISHAPE Firmware Application Note Kernel DB09 P-VIP® Lamp Systems 8. Memory Map Both, the segment definition table and the sequence string are stored in the lamp driver’s memory. The lamp driver is able to switch between waveforms. Different waveforms share the same segment definition table. The total waveform memory is shared between segments and sequences according to the memory table below. All addresses given here are decimal numbers. Memory addresses are subject to change with the lamp driver’s firmware. The starting address of the waveform information is 0xBD in EEPROM and 0x81E8 in SRAM for the DB08 kernel. Alternatively the waveform information starting addresses can be read out by UART. Please refer to the “UART Protocol” application note for further information. For changing the whole waveform data in EEPROM please refer to the application note “Firmware update”. The addresses shown in the memory map table are relative to the starting address in both, SRAM and EEPROM. The waveform information consists of the following main parts: 1. General information about all stored waveforms 2. Waveform Headers 3. Segment Types Definition Table 4. Sequences The Waveform memory is organized as a shared memory area. That has the advantage that the user can decide himself if he wants to store more segment types or more sequences. The sub-structure of the waveform information parts is as follows: 1. General information Byte 0: Total memory for waveform data in Bytes Byte 1: Total number of sequences 2. Waveform Headers Byte 0: Waveform ID number Byte 1: Starting address of the sequence (low byte) Byte 2: Starting address of the sequence (high byte) Byte 3: Free running frequency in 2Hz Byte 4: Maximum synchronization frequency in 2Hz Byte 5: Minimum synchronization frequency in 2Hz Byte 6: The sum of all dfactor over the whole waveform (low byte) Byte 7: The sum of all dfactor over the whole waveform (high byte) 3. Segment Type Definition Table Byte 0: Segment Height (h-factor) Byte 1: Segment Duration (d-factor) Byte 2: Segment Properties 4. Sequences Byte 0: First segment’s type 2007-03-19 Page 10 of 13 Gen3 UNISHAPE Firmware Application Note P-VIP® Lamp Systems Kernel DB09 Byte 1: Second segment’s type Byte 2: … Byte n-1: Last segment’s type Byte n: End of sequence indicator Memory map: Address 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 50 51 52 53 54 55 56 57 58 59 60 61 • • • • • • 2007-03-19 Waveform Headers Segment Type Definition Sequences general information Waveform Header 0 Segment type definition 0 Waveform Header 1 OR Segment type definition 1 Segment type definition 2 Waveform Header 2 OR Segment type definition 3 Segment type definition 14 Waveform Header 8 OR Segment type definition 15 Segment type definition 16 Waveform Header 9 OR Segment type definition 17 • • • 0 1 2 3 4 5 • • • • • • Page 11 of 13 Gen3 UNISHAPE Firmware Application Note Kernel DB09 P-VIP® Lamp Systems 9. Safety features The microcontroller’s firmware is protected against malfunction by a hardware watchdog timer. If the software does not work properly the hardware-controlled watchdog timer resets the microcontroller not later than after 16ms. 10. Guidelines for Creating Waveforms Although very complex light waveforms are now possible, the lamp needs to be operated within its specification in order to ensure optimal performance and best life time. The following paragraphs are guidelines for creating waveforms. OSRAM will publish a separate application note about waveform design soon. 10.1 Plateau levels All plateau level shall not vary more than 30% from each other. 10.2 Lamp maintenance pulses with commutations Proper lamp maintenance pulses are very important in order to achieve the specified lamp life time. The number of lamp maintenance pulses per waveform defines the lamp current frequency. The calculation formula is as follows: f lamp current = f waveform ⋅ nnumber of pulses 2 This number shall lead to a frequency that is within the specified lamp frequency range. It’s recommendable to choose an odd number of lamp maintenance pulses in order to balance any DC current automatically. The height and duration of the pulses must be within the range given in the lamp specification Place the pulses as much equally spaced as possible. The minimum and maximum time between two lamp maintenance pulses can be looked up from the lamp specification. 10.3 Low pulses The low pulse’s achievable level range is from 25% to 100%. The width shall not exceed 350µs. For now the number of low pulses is limited to one between two lamp maintenance pulses. The placement shall not be directly before or after a commutation. 11. Dynamic Dimming 12. Specification 12.1 Minimum SCI frequency The minimum SCI frequency is 30Hz at the moment. 12.2 Segment height limitations Segment currents can be from 0% up to 200% of the mean lamp current. The light output follows the lamp current with some delay. Therefore on a very fast time scale the relationship between lamp current and light output is not linear. 2007-03-19 Page 12 of 13 Gen3 UNISHAPE Firmware Application Note Kernel DB09 12.3 P-VIP® Lamp Systems Segment duration limits The minimum segment width is 75µs with no overshoot reduction. The overshoot reduction increases minimum pulse width. The maximum segment duration is 4ms. Please use multiple similar segments if you need more time. 12.4 Changing the waveform Modification of the waveform is only possible via the UART interface. The user can choose between modifying the SRAM memory or the EEPROM memory. SRAM changes can be done on-the-fly even during lamp operation. With an input power cycle the SRAM content is lost and will be restored with the waveform stored in the EEPROM memory. EEPROM changes are permanent changes of the stored waveform. The UART interface is not needed for lamp operation. 13. Kernel revision history DB09 • Improved voltage measurement algorithm. DB08 • smoothed current changes: the table driven algorithm was replaced by a vector based one. The current accuracy during lamp runup phase was improved from 8 bit to true 10 bit resolution. Also the voltage resolution was increased from 8 bit to 12 bit. • reduced the minimum segment duration by simplifying the waveform calculation. Waveform definition change was needed. • instant synchronization after ignition: the UNISHAPE waveform is synchronized within 1 second after lamp ignition. Added the possibility of voltage controlled minimum and maximum hfactor. DB07 • fixed error report in UART communication module: after an protocol, frame or parity error occurred the lamp driver kept on sending error codes until it received a valid command again. This happened even when communication was not yet enabled. DB06 • UART communication fully complies with the requirements of TI’s standardized protocol • reduced unsynchronized lamp runup time to 10 seconds • improved lamp current stability during runup phase by adding 2 virtual bits current resolution • re-synchronization after waveform change need less than 1 second 2007-03-19 Page 13 of 13