Welp I pretty much solved the big problems I encountered over the past couple weeks. Ground issues — turned out I was attaching ground of one interface to Vdd on another interface. That was solved by actually...
PC xfer still not working
Well I completely rewrote the code. And surprisingly, it looks pretty similar to what I did before. I moved the store/transfer routine out of (being called from) the ISR to the main loop. As soon as the ISR detects a...
Of timing, and general progress
I’ve determined that programming is like whack-a-mole(only took me 15 years to figure this out!) Fix one problem, and another one that already works stops working. This is what happened to me yesterday. My ISR...
making progress on the MFM hardware decoding
The whole question I’ve had for the last couple days (and potentially the last couple months) is how do you turn the signal coming out of the floppy drive into 0’s and 1’s. This really isn’t MFM...
Am I reading MFM wrong?
I’m beginning to think that I don’t fully understand the signalling coming out of the drive. I understand the concepts behind MFM (I think), but the actual application to this project, I’m not so sure...
Schmitt Trigger
Welp, after talking with some smart guys on forums.parallax.com, it looks like the Schmitt Trigger feature on the SX is going to allow me to get rid of my 74HC132 that I’ve spent at least a couple hours messing...
Ground issues
Although I’ve been attempting to have a common ground for this whole project — I’m not sure that is going to happen. At least not at this stage of the game. I tried connecting the ground off the floppy...
SX microcontroller with 74HC132
Here’s a picture of the prototype coming together. From the top down on the breadboard, you see a pull-up resistor, on the input that comes in on the yellow wire. The output comes out of the grey wire on the right...
Using a 74HC132E to square up the wave
A nice gentleman from sci.electronics.* newgroup suggested I use a 74HC132 on his web page here.[local copy] Below is the result of using this design, it worked perfectly. Only required one IC, one resistor, and one...
Current status updated
Current status updated I was originally going to use a Microchip PIC, but they are just too darn slow. I gave up on the idea of using the PIC as a one-chip solution, and tried to use it as just a clock generator feeding...