Thanks B.Goode
I am learning Python because it is easier to plot and do graphics than with a PIC and C. I intend to learn PyVisa as well for my HP projects.
This project is to make a real time plotter for a Heathkit Curve Tracer. Moving on to an HP4193A Vector Impedance Meter, an HP4192A Impedance Analyzer, and any other instruments that were invented before the digital plotters were invented. The Hewlett Packard were designed for 2 pen ink and paper plotters where the pens moved, not the paper. They do have have HPIB plotter functions.
The PIC is far more versatile than a Pi for hardware connections. See this link
https://drive.google.com/file/d/1SUMeJ8 ... drive_link
That is a dual ADC logging to an 8k x 8 RAM. The PIC will not sample fast enough so once this is working I will use logic circuits around the ADC to speed it up, maybe feeding a FIFO. It is basically a two channel DSO. I like to get something simple working first, then enhance it.
Why don't I use a DSO? because it will not label the axis of the plots with units of impedance, phase, current, etc. Why don't I use my Tektronix 2465A 'scope? For the same reason and because it needs setting up and ties the 'scope up. Also I have friends who would like some of these projects.
Why do I bother? I'm 85 years old. I don't need a curve tracer I only do what I enjoy. I avoid frustration and I see Pyserial heading that way. I will use i2c that I have more confidence in and is working. For Pyserial I don't think I have the same control as i2c to ask for data and get it reliably.
Maybe when I get better at Python, and the need arises, I will have a go at Pyserial. Adafruit and others that sell ADCs, and sensors, use i2c or spi which is telling me something.
I had hoped to find out how Pyserial sends a request for data and knows when it arrives without control characters or sending ASCII. i2c does it with interrupts on a PIC.
I used my own protocol with RS485 to control my ROV over 300 ft of twisted pair with a master PIC and 4 slave pics controlling the ROV. That approach is too complicated and not necessary for this project. Python should be simpler.
https://drive.google.com/file/d/16_zzvg ... sp=sharing
I am learning Python because it is easier to plot and do graphics than with a PIC and C. I intend to learn PyVisa as well for my HP projects.
This project is to make a real time plotter for a Heathkit Curve Tracer. Moving on to an HP4193A Vector Impedance Meter, an HP4192A Impedance Analyzer, and any other instruments that were invented before the digital plotters were invented. The Hewlett Packard were designed for 2 pen ink and paper plotters where the pens moved, not the paper. They do have have HPIB plotter functions.
The PIC is far more versatile than a Pi for hardware connections. See this link
https://drive.google.com/file/d/1SUMeJ8 ... drive_link
That is a dual ADC logging to an 8k x 8 RAM. The PIC will not sample fast enough so once this is working I will use logic circuits around the ADC to speed it up, maybe feeding a FIFO. It is basically a two channel DSO. I like to get something simple working first, then enhance it.
Why don't I use a DSO? because it will not label the axis of the plots with units of impedance, phase, current, etc. Why don't I use my Tektronix 2465A 'scope? For the same reason and because it needs setting up and ties the 'scope up. Also I have friends who would like some of these projects.
Why do I bother? I'm 85 years old. I don't need a curve tracer I only do what I enjoy. I avoid frustration and I see Pyserial heading that way. I will use i2c that I have more confidence in and is working. For Pyserial I don't think I have the same control as i2c to ask for data and get it reliably.
Maybe when I get better at Python, and the need arises, I will have a go at Pyserial. Adafruit and others that sell ADCs, and sensors, use i2c or spi which is telling me something.
I had hoped to find out how Pyserial sends a request for data and knows when it arrives without control characters or sending ASCII. i2c does it with interrupts on a PIC.
I used my own protocol with RS485 to control my ROV over 300 ft of twisted pair with a master PIC and 4 slave pics controlling the ROV. That approach is too complicated and not necessary for this project. Python should be simpler.
https://drive.google.com/file/d/16_zzvg ... sp=sharing
Statistics: Posted by PeterRovman — Sat May 10, 2025 4:05 pm