++++++++++++++++++++++++++++++++++++++++++ + METHODS + ++++++++++++++++++++++++++++++++++++++++++++ Sokol/Infotek. Here is an article by Denis Zodchenko: AY has three registers that specify channel volume. If according to the corresponding The generator is turned on on the current channel - this will tone volume. If it's off, it will be 4-bit DAC. In both cases, this value has a local garithmic dependence. Increase by one means increasing the volume/u- equal to the square root of two. Uwe- dividing by two - accordingly, by two times - for. It was made from ergonomic considerations - human hearing has a log- rhyme diagram of sensitivity, the lower the volume, the more sensitive exactly ear to the same linear change in sound power (namely power ty, volume is puresubjective concept). That is, if linearly increasing enter the volume number of the tone generator, per hearing volume will increase almost linear, and power - logarithmic. When AY works as a DAC one at a time or several channels - this logarithmic logical dependence is not very convenient. But works :-) Having connected AY to BC at one time, I "invented" (too loud a word, but that's it) g) method of improving quality when losing single digitization (without mixing) of a bunch of channels). The method is as follows: in advance (in Basi- ke, for example) TWO tables are calculated. The values in these tables are as follows: for each up to one of the desired output levels all pairs of values written in AY are tions in such a way that the arithmetic mean the logical result was closest to the desired level. 256 options (pair 4-bit values) for each of the 256 re- results. Playback is carried out as follows: for each of the digitization byte, two corresponding corresponding values, and SEVERAL TIMES are next written to the AY ports. This occurs at ultrasonic frequency, and the human ear of this alternation is simplydoesn't notice. The ear actually hears the same thing the desired average value. As a result DAC AY becomes, as it were, not even human 3-bit, or even better :-) Playback is carried out from the IDE hard drive, also in a rather cunning way - bom. The screw is initially given the command to chi- get away from the right place. When he gives out the accuracy, the program lost another digitization byte, and between alternating characters read data from the screw (four bytes ta). Thus, while it was playing 128 bytes, the sector in memory. While playing the following 384 bytes the screw managed to read the next one sector to its internal buffer and issue readiness. The speeds of even the ancient 20-me- Prairietek 120 shit was enough for to linearly read and play eight-bit new digitization. At this time, against the backdrop of the car- Teens on the screen were playing something rough similar to an oscilloscope (XOR of a new one was made byte - a dash appeared in the vertical cal column, XOR old - disappeared previously stated). A sort of digital magician nitofon :) However, this player is just as successful could play on covox.
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