A system is provided for recording, storing and reproducing sound for playing back in an environment requiring simulated sounds, voices, and/or sound effects. Sounds are recorded on a chip and played back in an asynchronous manner from the chip as a result of activation of a switch or inertial movement within the system. A Hall-effect sensor, reed switch or momentary switch or the like may be implemented for enabling activation of the recorded sound from the chip for broadcasting. A compander compresses the sound on the chip and expands the compressed sound for playback. Employing the above system for audio storage, a sound, motor and special effects controller may be created for model train applications as well. The different functions of the sound unit are controlled through a discrete bi-polar digital command control signal using a unique address for each unit. A synchronous means of play back may also be employed when the system is used with the bi-polar signal using a sensor. In addition to the analog sound storage, the same concepts and ideas may be applied to a digital sound recording and play back device as well.
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0. 21. A sound reproducing system for a model train traveling on a plurality of rails that uses an amplified digital control signal for propulsion and control, the system comprising:
a sound unit;
a memory within the sound unit wherein the memory stores a plurality of sound effects at addresses wherein the sound effects contain multiple samples that emulate a train locomotive at various speeds and various work-loads wherein the memory has an analog wave form representing sound effects of a locomotive at the various speeds and the various work-loads or a digital representation of the analog wave form that represents a plurality of sound effects of a locomotive at the various speeds and the various work-loads wherein the sound effects simulate the various speeds and the various work-loads by comparing the on-off rate of a sensor to a digital speed packet; and
a controller connected to the memory for recalling at least one of the sound effects wherein the controller is controlled by a digital signal.
0. 1. A sound reproducing system for a model train traveling on a plurality of rails that uses a amplified digital control signal for propulsion and control, the system comprising:
a sound memory storing a plurality of sound effects at predetermined addresses;
a controller connected to the sound memory for recalling the sound effects of either one or a plurality of sound effects in a predetermined sequence or a random sequence;
a sound memory containing multiple samples that emulate a model locomotive at various speeds and work loads;
an integrated sound, motor and special effects controller controlled by a bi-polar digital signal, the motor and special effects controller re-producing the stored sounds contained in the model train; and
a digital packet triggering a sound effect for automatic playback of a sound effect.
0. 2. The system according to
0. 3. The system according to
an electrical power supply in the rail car or track side structure having a means for collecting the digital bi-polar signal from either of the two insulated tracks by a pick up on two insulated wheels or off of a digital buss line or overhead wire;
a full wave bridge rectifier with an input connected to a bi-polar digital signal with an output producing a DC voltage regardless of the phase of the bi-polar signal;
a regulated power supply connected to a full wave bridge rectifier supplying power to the sound reproducing system; and
a regulated power source for the audio amplifiers.
0. 4. The system according to
means for simultaneously decoding a properly addressed digital control packet for control of the model locomotive's electric motor, control of the sound functions and on board special effects.
0. 5. The system of
a fixed external source of either AC or DC power and means for connecting a bi-polar digital signal to the sound unit;
means for filtering the low level signal noise in the reception of the bi-polar digital signal for power and control of the sound unit.
0. 6. The system of
means to synchronize sound effects through the use of a Hall effect sensor to trigger a plurality of speed sensitive sounds located in a model train locomotive or rail car based on a digital speed packet wherein the speed sensitive sounds are stored in the memory and include various samples that emulate different speeds and loads;
a controller that recalls the same plurality of synchronized sound effects at intervals appropriate to the speed of the locomotive depending on a digital command control speed packet wherein the same controller recalls a plurality of synchronized sound effects at intervals appropriate to the speed of the locomotive using a speed sync sensor and further wherein the controller recalls asynchronous sound effects from the same memory or from additional memories for sound on sound.
0. 7. The system of
0. 8. The system of
a controller that will decode a three byte packet with an addressed header that matches the sound unit's discreet address in the range of 1 to 127 addresses for controlling a model train locomotive motor, sound effects and onboard special effects.
0. 9. The system of
a controller that decodes a four byte packet with an address header that matches the sound units discreet address in the address range of 1 through 9999 for controlling a model train locomotive motor, sound effects and onboard special effects.
0. 10. The system of
means for synchronizing the sound effects to the driver's wheels through decoding a properly addressed digital speed packet that controls the speed of the model locomotive and determines which sound effect to synchronize with the speed of the locomotive using the same digital speed packet.
0. 11. The system of
a Hall effect sensor to sense a change of speed of wheels of a steam locomotive to trigger the proper speed sound effect by mounting a magnet to the rear of a drive wheel to form a switch closure for synchronization of the sound effect to the digital speed control packet.
0. 12. The system of
a micro-controller that decodes a predetermined addressed digital signal for control of sound effects, model train propulsion and on board special effects wherein the micro-controller is operatively connected to the analog sound storage of the sound effects wherein the analog sound storage has a predetermined set of sounds at specific addresses; and
a controller that is connected to special effects outputs that control lighting and other onboard effects.
0. 13. The system of
0. 14. The system of
0. 15. The system of
means for changing the break points at which the digital speed packet triggers the related sound effects through end user accessible software on the micro-controller or as defined as configuration variables.
0. 16. The system of
a plurality of digitized sounds that are controlled by the controller that receives a bi-polar digital signal.
0. 17. The system of
0. 18. The system of
a magnet; and
a pendulum on which the magnet is suspended wherein motion causes the magnet to transpose resulting in a change in the magnetic field.
0. 19. The system of
a microphone constructed and arranged to record the at least one additional characteristic sound on the sound module means.
0. 20. The system of
0. 22. The system of
0. 23. The system of
0. 24. The system of
0. 25. The system of
0. 26. The system of
0. 27. The system of
0. 28. The system of
0. 29. The system of
0. 30. The system of
0. 31. The system of
an electrical power supply connected to at least one of the plurality of rails;
a pick-up means for collecting the digital signal; and
a full-wave bridge rectifier connected to the electrical power supply and further having an input for receiving the digital signal and an output wherein the output produces a DC voltage without regard to phase of the digital signal.
0. 32. The system of
0. 33. The system of
a fixed external source of electrical power;
means for connecting the digital signal to the sound memory; and
means for filtering the digital signal.
0. 34. The system of
a speed sync sensor in the controller wherein the controller recalls a plurality of speed sensitive sounds to emulate a speed of the train locomotive based on a speed of the model train wherein the speed sync sensor synchronizes the speed sensitive sounds with the speed of the model train.
0. 35. The system of
0. 36. The system of
a second memory for storing the plurality of sound effects.
0. 37. The system of
a discrete address in the range of 1 to 127 contained within the sound unit wherein the digital signal includes a three byte packet wherein the three byte packet includes an address header that matches the discrete address.
0. 38. The system of
a discrete address in the range of 1 to 9999 contained within contained within the sound unit wherein the digital signal includes a four byte packet wherein the four byte packet includes an address header that matches the discrete address.
0. 39. The system of
wheels on the model locomotive;
a digital packet within the digital signal for controlling a speed of the model locomotive; and
means for synchronizing the plurality of sound effects to the wheels of the model locomotive wherein the synchronization means decodes the digital packet and further wherein the synchronization means determines which sound effect to synchronize with the speed of the model locomotive using the digital packet.
0. 40. The system of
0. 41. The system of
0. 42. The system of
0. 43. The system of
0. 44. The system of
0. 45. The system of
0. 46. The system of
a microphone on the sound unit for recording an additional sound effect.
0. 47. The system of
an activation means for activating the sound effect wherein the activation means is a magnetically responsive sensor.
0. 48. The system of
means for controlling a variable filter network wherein the variable filter network suppresses audible noise.
0. 49. The system of
0. 50. The system of
0. 51. The system of
0. 52. The system of
0. 53. The system of
0. 54. The system of
0. 55. The system of
a first circuit board having a plug; and
a second circuit board having a socket wherein the plug of the first circuit board connects to the socket of the second circuit board.
0. 56. The system of
a controllable filter network reducing vibrations in a motor.
0. 57. The system of
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input 38 may be connected as an input for recording of sounds on the chip 14. Alternatively, the DAST™ chip 14 is provided with a built-in microphone for recording of sounds thereon.
The present invention will be described with reference to a livestock sound module used with a model railroad car which plays pre-recorded messages when activated, although it should be understood that any environment requiring playback of sound may implement the sound reproducing and recording system of the present invention. Up to six basic components or sections may be implemented to perform the features embodied by the principles of the present invention.
The first section is the power supply previously described. The power supply when used with a model railroad car may run off of track voltage wherein the power is input to a full-wave bridge rectifier and a capacitor acting as a filter. The output is then connected to a voltage regulator. The nine volt DC input from, for example, a nine volt DC battery, is tied in at a node through a diode. If a nine volt battery is used in conjunction with the track power, the battery acts as a low voltage backup keeping the module voltage up when the track voltage drops off or shuts off. Power is switched to the module via the SPST switch.
The second section of the present invention is the DAST™ analog sound effects chip and audio expander. The DAST™ analog sound effects chip is capable of storing between twelve seconds and 120 seconds of analog data in a non-volatile analog memory. Various audio messages can be programmed into the sound effects chip. The library messages are stored on, in a preferred embodiment, a digital audio tape audiotape. When the messages are programmed, the analog audio signal is played back at a pre-recorded level and sent through a compressor. A compander is used in the present invention which reduces the dynamic range of the signal before it is recorded into the chip. When the sound effects are played back from the chip, they are played back through an audio expander. The expansion does two things: the audio is expanded and the signal is restored to its original dynamic range; and when the audio is expanded, low-level audio noise in the system is attenuated giving an improved signal-to-noise ratio.
The third section of the circuit is the audio amplifier. In a preferred embodiment, the amplifier is an LM386N-1. The output of the audio amplifier is capacitively coupled to a volume potentiometer. The wiper of the potentiometer is the input of the amplifier. The output of the amplifier is capacitively coupled and connected to a speaker.
The fourth section of the circuit is the message activation or chip enabling section of the circuit. Pin 23 of the sound effects chip is the chip enable. Chip enable is an active low signal, and the pin is pulled high with a resistor and a decoupling capacitor in parallel. The configuration of the device initiates the message inside the chip to be played by pulling of the pin to ground. The message plays once unless the pin is held low. If held low, the message continues to repeat until the pin is allowed to get pulled to high.
The pin can be activated several ways as previously set forth. A Hall-effect sensor below a suspended magnet may be implemented in a preferred embodiment. When a train car travels along or is jarred on a track, the change in the magnetic field from the magnet swaying causes the Hall-effect sensor to activate and give a momentary pull to ground thereby initiating the chip. Therefore, the present invention is activated by inertia-sensitive control.
The fifth section of the present invention is the option of recording custom messages. The chip has a built-in microphone amplifier that can be used to record audio data. This is controlled by the state of the playback/record pin. When held low, the chip is then put into record mode and will record audio as long as the chip enable is held low. Alternatively, an external microphone may be implemented for recording on the chip.
Referring to
To record a new message on the chip, two pins on the chip are controlled, /Chip Enable and Playback/Record. /Chip Enable controls the start of both the record and play cycles. The level of the Playback/Record pin will determine whether a new message is to be recorded or the saved message played back. Pin 27 (P/R) is normally held high and messages play back as long as chip enable (/CE pin 23) is held low. If P/R is pulled to ground and then /CE is pulled low, the chip is then automatically placed into record mode and records the analog signals in real time picked up by the microphone. Recording stops when /CE is brought high. As previously mentioned, by controlling the address or logic level, the location of the new message can be controlled such that it will not record over previous audio.
Due to the limited space available within model train locomotives and cars, the present configuration uses two narrow elongated printed circuit boards (PCB's) stacked upon each other on which the electronic components are mounted in this embodiment. The circuit boards are electrically interconnected by means of a multi-pin plug on the upper PCB and a mating socket on the lower PCB.
Referring now to
An alternate configuration uses a separate power source between 14 to 24 volts AC or DC which is connected to J2 section 109 on the upper PCB, and the jumpers set on J4 section 108 and J5 section 108 are placed between pins 1 and 2 on each while a bi-polar digital signal is attached to J3 section 108.
In either configuration, the unregulated AC, DC, or bi-polar DC power source passes through fuses F1 and F2 section 109. These fuses protect both legs of the power source and, to some degree, protect from shorts, overloads, or other faults involving the present invention or associated field wiring. The power source is then passed through a bridge rectifier (BR1) section 109 to two voltage regulators, VR1 (MC7812CT) 109 and VR2 (MC7805CT) section 109 to associated filter and decoupling capacitors. A heat sink is attached to VR1 and VR2 section 109.
The result is three power supply potentials consisting of a “V+” unregulated output for sourcing the special effects outputs and motor control. a A regulated “+12 vdc” powers the audio amplifier circuitry, and a regulated “+5 vdc” to power the logic circuitry.
The digital signal whether input through J3 section 108 or J2 section 109 is half-wave rectified by D1 section 108, current limited by R3108, and is annunciated by LED 1 section 108. It then enters a Schmitt trigger opto1 opto-isolator, (OPTO) (OPTO1) section 108. The opto-isolator provides a safety layer of isolation between the signals input and field wiring in the model setting. The Schmitt trigger aspect protects from data errors due to low level low-level digital noise. The digital signal exits the opto-isolator in an inverted state and enters a micro-controller (IC1) through the Input No. 2 line section 101.
The micro-controller's speed is set by a Crystal (XTAL 1) section 102 and an on board on-board oscillator.
There are several output lines associated with the micro-controller section 101. Two of the lines, output 10 and output 9, are connected to the gates of driver MOSFET transistors, Q1 and Q2 section 106, which are open drain, active low auxiliary outputs; function No. 0 and function No. 1 (F0 and F1) section 106. The transistors have current limiting resistors R1 and R2 section 106 connected to the drain-source path, in series with the load. The current limiting resistors' values are selected according to the load(s). In a typical model railroading application, Q1 is connected to a flashing LED beacon or similar device and is controlled as F1. Q2 is connected to the locomotive headlight and is controlled as F0. The use of F0 as head lamp control is based upon the NMRA DCC standard; however the function outputs can be re-configured for different loads and control assignments.
Output lines 1-4 section 105 are connected to the gates of driver MOSFET transistors, Q3-Q6 arranged in an H-bridge configuration section 107 for pulse width modulated bi-directional control of a DC motor. A controllable filter network is connected across the DC motor for the modification of motor drive wave shapes for the suppression of undesirable audible noise section 107.
Output lines 5-8 section 104 are connected to the serial EEPROM section 103 and a shift register section 111. The serial EEPROM contains many memory registers which contain information that is used to define various operating characteristics of the invention. Most of these registers are defined by the NMRA and are termed Configuration Variables (CV or CV's). Some of the registers are set aside for application specific uses defined by the manufacturer. Most of the CV's can be altered by the hobbyist through programming. The digital address of the sound effect to be played is loaded by the micro-controller into the shift register section 111.
Output line 11 and input line 3 on the micro-controller section 101 are connected to the multi-pin plug section 110 which routes signals to the lower PCB.
Now refer to
The DAST™ chip (sound effect chip), IC5 section 201 is the first section of the circuit component on the lower PCB. The DAST™ chip is capable of storing between twelve seconds and 120 seconds of analog data in a non-volatile memory. Various audio sound effects can be programmed into the DAST™ chip. The location of the various sound effects in the DAST™ chip are assigned by setting the appropriate bits on the DAST™ chip's address inputs. At the time of recording, these address locations may be set by some type of development system. During playback, the address locations are set by the micro-controller IC1 section 101.
When the sound effects are played back from the chip as set by the microcontroller IC1 section 101, they are played back through an audio compander section 204. The expansion docs two things: the audio is expanded and the signal is restored to its original dynamic range; and when the audio is expanded, low-level audio noise in the system is attenuated giving an improved signal-to-noise ratio.
The third section of the circuit is the audio amplifier. In a preferred embodiment, the amplifier is an LM386N (IC4) section 205. The output of the audio expander is capacitively coupled to a volume potentiometer. The wiper of the potentiometer is the input of the amplifier. The output of the amplifier is capacitively coupled and connected to a potentiometer.
The fourth section of the circuit is the sound effect activation or chip enabling section of the circuit. One pin of the DAST™ integrated circuit (IC5) section 201 is the chip enable. Chip enable (/ce) is an active low signal, and the pin is pulled high with a resistor. Chip enable is connected with output line 11 on the micro-controller. Sound effect playback is initiated by loading the appropriate address bits into the shift register section 111 on the upper PCB and then bringing chip enable low. Typically, for playback of a single sound effect, /ce is brought high after sound effect playback begins. If playback of consecutive sound effects is desired, /ce is left low. At the end of each sound effect, a signal is generated on another pin of the DAST™ chip (IC5) called End of Message (/com) (active low). /com is connected to input line No. 3 of the micro-controller section 101 through socket J7 section 203 and J1 section 110. If it is desired to repeat a sound effect, either with spaced repetition or with seamless looping, /eom is monitored to mark the end of the current sound effect being played allowing the micro-controller to precisely control repetition or looping.
PNP transistors Q3 and Q4 section 206 have their bases connected to A6 and A7, respectively, and their collectors are tied to ground. The open emitters of Q3 and Q4 are connected to a pin of the DAST™ chip (IC5) section 201 which is labeled Power Down, an active high input. Power Down is connected to a pull up resistor (R14) section 206 and a decoupling capacitor (C18) section 206. When A6 and A7 are both high, Power Down goes high and the DAST™ chip (IC5) is taken into a standby state and reset. This is useful if the DAST™ chip (IC5) should ever become errant in operation or if it is desirable to interrupt a sound effect being played before it has reached completion.
Now refer to
A digital synthesizer integrated circuit IC6 in section 301 is now used for the production of sound effects. The present invention uses a Part No. YM3812 sound generator from Yamaha Systems Technology; San Jose, Calif. for IC6 section 301. Sound effects are created by alternately loading address and data information into lines D1-D8 on IC6 section 301. The alternating action is controlled by a flip-flop section 306. A digital to analog converter (DAC) section 304 is used to change the digital outputs of IC6 section 301 into varying voltages, which are the sounds. In the present invention, a Part No. YM3014 from Yamaha Systems Technology, San Jose, Calif. is used for the DAC. The output of the DAC feeds into a unity gain buffer section 305. The output of the buffer feeds into a low pass filter section 307 before reaching the volume control potentiometer R11 which is part of the audio amplifier circuit section 305. In the present configuration, the amplifier is an LM386N (IC4) section 305 from National Semiconductor, Inc., Santa Clara, Calif. The wiper of the potentiometer is in input of the amplifier. The output of the amplifier is capacitively coupled and connected to a speaker.
Now a detailed explanation of the software operation will be given. Refer now, additionally, to
Beginning at <START> section 501, the micro-controller section 101 is initialized in section 502. The appropriate lines are configured as either input or output. Initial values are loaded into specified registers of the micro-controller section 101. One important value is the address which is loaded section 503 from the serial EEPROM section 103. The address determines which data transmissions are intended for the device to act upon. Input line No. 2 on the micro-controller section 101 then begins to receive transmitted data from the components in section 108. The present invention is configured to accept data transmissions based upon a digital protocol “Digital Command Control” DCC; a standard established and maintained by the National Model Railroad Association, Chattanooga, Tenn.
Refer now additionally to
Refer alternately to
Once a complete packet is received, the software then checks the validity of the data by performing an error check in section 506. The error check requires that the Exclusive-Or logical function be performed upon the address byte and the data byte. If the result of this operation matches the value of the error byte, the packet is valid. If the packet is rejected as invalid, the software loops back to section 504 to await the next preamble.
If the data is deemed valid, it is first checked in section 507 to see if this was a baseline idle packet. Idle packets are part of the DCC standard and are often used for time delays. If an idle packet is detected, the software loops back to section 504 to begin receiving the next preamble, as no further action is required.
If the packet was found not to be an idle packet, several tests are performed to determine what action is to be taken based upon the data. In each case, a failed test causes a branch to the next test.
Beginning with test section 508, if it is determined, this data is intended for any and all devices receiving the data; or as termed by the DCC standard, a broadcast command. If it is, a branch is taken at section 515. At the completion of the branch, the software is at section 521 of FIG. 12. The broadcast command data is tested to see if an emergency stop command has been issued at section 522. If an emergency stop command is detected, the appropriate actions are taken to effect affect an emergency stop of the model train locomotive section 523. The software then branches at section 524 back to
Referring now to
Now referring to
Moving back to
Referring now back to
Referring back to
Referring now to
Once an engine speed sound effect has been selected, it is compared with the previously selected engine speed sound effect section 580. If the most recently selected sound effect is a higher and faster sound effect, a transitional acceleration sound effect is selected first at section 581. The status of function #4 mute, from the previously received function group #1 is now checked at 582. If function #4 is active, the selected engine speed or acceleration sound effect is loaded at 583. If function #4 mute is inactive, the software continues without loading an engine speed or acceleration sound effect. Whether or not a speed or acceleration sound effect is loaded, the software continues forward to see if higher priority sound effects should be played. Next, function #3 from function group #1 is now checked at section 584. If function #3 is active, the bell sound effect is loaded at section 585. If function #3 is inactive, the software will continue without loading the bell sound effect. Next, function #2 from function group #1 is now checked at section 586. If function #2 is active, a further test is conducted to see if this is the first time function #2 has been found to be active at section 587. If this is the first time function #2 is found to be active, the first horn or whistle sound effect is loaded for model train diesel or steam locomotives, respectively, at section 589. If the second time function #2 is found to be active, the second horn or whistle sound effect is loaded for model train diesel or steam locomotives, respectively, at section 588. Through concatenation, the model train enthusiast can create realistic horn and whistle cadences. A test is now performed to see if a steam engine speed effect has been loaded at section 590. If it is not, the last loaded sound effect is now played at section 592. If no sound effects have been loaded, no sound effects are played. This would indicate that functions #2, #3, and #4 are inactive thereby preventing the loading of the horn, whistle, bell, and engine speed sound effects, respectively. If the loaded sound effect is found to be a steam engine speed sound effect in section 590, a further test is performed to see if a Hall-effect wheel sync device in
Referring now to
Referring now to
Referring now to
Referring now to
It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages. It is, therefore, intended that such changes and modifications be covered by the appended claims.
Novosel, Michael J., Fleszewski, III, Vincent S., Poles, Kelly
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