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diff --git a/Documentation/video4linux/radiotrack.txt b/Documentation/video4linux/radiotrack.txt deleted file mode 100644 index d1f3ed199..000000000 --- a/Documentation/video4linux/radiotrack.txt +++ /dev/null @@ -1,147 +0,0 @@ -NOTES ON RADIOTRACK CARD CONTROL -by Stephen M. Benoit (benoits@servicepro.com) Dec 14, 1996 ----------------------------------------------------------------------------- - -Document version 1.0 - -ACKNOWLEDGMENTS ----------------- -This document was made based on 'C' code for Linux from Gideon le Grange -(legrang@active.co.za or legrang@cs.sun.ac.za) in 1994, and elaborations from -Frans Brinkman (brinkman@esd.nl) in 1996. The results reported here are from -experiments that the author performed on his own setup, so your mileage may -vary... I make no guarantees, claims or warranties to the suitability or -validity of this information. No other documentation on the AIMS -Lab (http://www.aimslab.com/) RadioTrack card was made available to the -author. This document is offered in the hopes that it might help users who -want to use the RadioTrack card in an environment other than MS Windows. - -WHY THIS DOCUMENT? ------------------- -I have a RadioTrack card from back when I ran an MS-Windows platform. After -converting to Linux, I found Gideon le Grange's command-line software for -running the card, and found that it was good! Frans Brinkman made a -comfortable X-windows interface, and added a scanning feature. For hack -value, I wanted to see if the tuner could be tuned beyond the usual FM radio -broadcast band, so I could pick up the audio carriers from North American -broadcast TV channels, situated just below and above the 87.0-109.0 MHz range. -I did not get much success, but I learned about programming ioports under -Linux and gained some insights about the hardware design used for the card. - -So, without further delay, here are the details. - - -PHYSICAL DESCRIPTION --------------------- -The RadioTrack card is an ISA 8-bit FM radio card. The radio frequency (RF) -input is simply an antenna lead, and the output is a power audio signal -available through a miniature phone plug. Its RF frequencies of operation are -more or less limited from 87.0 to 109.0 MHz (the commercial FM broadcast -band). Although the registers can be programmed to request frequencies beyond -these limits, experiments did not give promising results. The variable -frequency oscillator (VFO) that demodulates the intermediate frequency (IF) -signal probably has a small range of useful frequencies, and wraps around or -gets clipped beyond the limits mentioned above. - - -CONTROLLING THE CARD WITH IOPORT --------------------------------- -The RadioTrack (base) ioport is configurable for 0x30c or 0x20c. Only one -ioport seems to be involved. The ioport decoding circuitry must be pretty -simple, as individual ioport bits are directly matched to specific functions -(or blocks) of the radio card. This way, many functions can be changed in -parallel with one write to the ioport. The only feedback available through -the ioports appears to be the "Stereo Detect" bit. - -The bits of the ioport are arranged as follows: - - MSb LSb -+------+------+------+--------+--------+-------+---------+--------+ -| VolA | VolB | ???? | Stereo | Radio | TuneA | TuneB | Tune | -| (+) | (-) | | Detect | Audio | (bit) | (latch) | Update | -| | | | Enable | Enable | | | Enable | -+------+------+------+--------+--------+-------+---------+--------+ - - -VolA . VolB [AB......] ------------ -0 0 : audio mute -0 1 : volume + (some delay required) -1 0 : volume - (some delay required) -1 1 : stay at present volume - -Stereo Detect Enable [...S....] --------------------- -0 : No Detect -1 : Detect - - Results available by reading ioport >60 msec after last port write. - 0xff ==> no stereo detected, 0xfd ==> stereo detected. - -Radio to Audio (path) Enable [....R...] ----------------------------- -0 : Disable path (silence) -1 : Enable path (audio produced) - -TuneA . TuneB [.....AB.] -------------- -0 0 : "zero" bit phase 1 -0 1 : "zero" bit phase 2 - -1 0 : "one" bit phase 1 -1 1 : "one" bit phase 2 - - 24-bit code, where bits = (freq*40) + 10486188. - The Most Significant 11 bits must be 1010 xxxx 0x0 to be valid. - The bits are shifted in LSb first. - -Tune Update Enable [.......T] ------------------- -0 : Tuner held constant -1 : Tuner updating in progress - - -PROGRAMMING EXAMPLES --------------------- -Default: BASE <-- 0xc8 (current volume, no stereo detect, - radio enable, tuner adjust disable) - -Card Off: BASE <-- 0x00 (audio mute, no stereo detect, - radio disable, tuner adjust disable) - -Card On: BASE <-- 0x00 (see "Card Off", clears any unfinished business) - BASE <-- 0xc8 (see "Default") - -Volume Down: BASE <-- 0x48 (volume down, no stereo detect, - radio enable, tuner adjust disable) - * wait 10 msec * - BASE <-- 0xc8 (see "Default") - -Volume Up: BASE <-- 0x88 (volume up, no stereo detect, - radio enable, tuner adjust disable) - * wait 10 msec * - BASE <-- 0xc8 (see "Default") - -Check Stereo: BASE <-- 0xd8 (current volume, stereo detect, - radio enable, tuner adjust disable) - * wait 100 msec * - x <-- BASE (read ioport) - BASE <-- 0xc8 (see "Default") - - x=0xff ==> "not stereo", x=0xfd ==> "stereo detected" - -Set Frequency: code = (freq*40) + 10486188 - foreach of the 24 bits in code, - (from Least to Most Significant): - to write a "zero" bit, - BASE <-- 0x01 (audio mute, no stereo detect, radio - disable, "zero" bit phase 1, tuner adjust) - BASE <-- 0x03 (audio mute, no stereo detect, radio - disable, "zero" bit phase 2, tuner adjust) - to write a "one" bit, - BASE <-- 0x05 (audio mute, no stereo detect, radio - disable, "one" bit phase 1, tuner adjust) - BASE <-- 0x07 (audio mute, no stereo detect, radio - disable, "one" bit phase 2, tuner adjust) - ----------------------------------------------------------------------------- |