Audio storage of programs
Posted: 28 Aug 2018, 19:43
With the creation of BASIC, I'm thinking of ways to store and load programs. I'd like to be independent of another computer. I think the best medium is something we have on hand these days - our smart phones. We could do what retrocomputers did and use audio medium to store and load programs. We have the means to store a program by connecting the audio output to the microphone input an hitting record on the phone. Then it's a simple toggling of the audio output in a defined way to encode the data. I think commodore did long and short pulses for zero and one or something.
Loading it back might be a little more difficult. I think commodore read it back by looking at it as a single data input and measuring the timing. I'm thinking the serial data input on the DB9 could be used for this. The only problem is that it only latches with HSYNC, so that might be too slow, but since we can define the output, we could make it slow enough to tolerate a slow readback. And I'm thinking there are low signal levels coming out of the phone even at high volume, but we could put an opamp in front to boost the signal or even overdrive it so we get square pulses. This could solve storing and load programs with maybe one opamp.
Anyone have experience with old tape drives? I do not - just what I've read on the internet.
Loading it back might be a little more difficult. I think commodore read it back by looking at it as a single data input and measuring the timing. I'm thinking the serial data input on the DB9 could be used for this. The only problem is that it only latches with HSYNC, so that might be too slow, but since we can define the output, we could make it slow enough to tolerate a slow readback. And I'm thinking there are low signal levels coming out of the phone even at high volume, but we could put an opamp in front to boost the signal or even overdrive it so we get square pulses. This could solve storing and load programs with maybe one opamp.
Anyone have experience with old tape drives? I do not - just what I've read on the internet.