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这种简易接口允许数据从2400比/秒的速率储存在普通磁带录音机里。串行数据列(见图1A)通过异或门IC1/1被2400Hz的时钟信号(B)编码。逻辑“高”和“低”如图2(C)所示。这些脉冲经过分压电阻降低幅度后加入普通磁带录音机的录音输入端。在录音机放音时,脉冲(D)被CMOS门IC1/2放大,该门接成线性放大电路,并提供TTL电乎信号,如(E)所示。在正、负两个转折点IC1/4产生如(F)所示的短脉冲(约50μs),并触发单触发电路IC2。把单稳态的单触发脉冲的宽度调整到位长的3/4(310μs)。在编码的脉冲中,从“高”变到“低”时产生一位单元宽度的“低”脉冲,同样从“低”变到“高”时产生同
This simple interface allows data to be stored in normal tape recorders at 2400 bps. The serial data column (see Figure 1A) is clocked by the 2400Hz clock signal (X) through the XOR gate IC1 / 1. Logic “High” and “Low” are shown in Figure 2 (C). These pulses are added to the tape recorder’s recording input after the voltage divider has been reduced. When the recorder is playing, the pulse (D) is amplified by the CMOS gate IC1 / 2, which is connected as a linear amplifier circuit and provides a TTL level signal as shown in (E). At the positive and negative turning points, IC1 / 4 generates a short pulse (about 50μs) as shown in (F) and triggers the one-shot circuit IC2. Adjust the monostable one-shot pulse width to 3/4 (310μs) of the bit length. In a coded pulse, a “low” pulse that produces a cell width when changing from “high” to “low”, also produces the same “low” pulse from “low” to “high”