We have talked to our client recently and have had to modify our relay setup. this is what each relay setup for each MFC will look like.
We have bought more relays for the other 3 MFCs that we need to read their values. We hope to reduce the amount of relays from 12, to just 10 relays.
We recently got our RTC chip and it was very easy to install, it uses I²C and just we had to use some Linux commands to get it to work. Now if the internet is down, the Raspberry Pi will still get the right time and date.
We are also looking into using a Raspberry Pi Zero instead of the Raspberry Pi B+ that we are currently using, because it is half the size and it can do everything our RPi can do.
Here are the current pins we are using on the RPi, excluding some Ground and some DC Power pins . We have plenty of pins left over for the LCD that we want to use. We want it to have the date, time, and when the last sample was taken. We could possibly have it to show the user any errors that are occurring.
We are still working on the sending data to a flash drive and to our server. We want to organize the data in the flash drive by year, month and day, with the file being named after the day. The data we want will include the date, time and the voltages for the two stages of each MFC. The website will show the data in a table and have graphs for each stage.
We bought a 12-bit ADC chip, MCP3204, to get better readings from the MFC, so we are not using our PIC18F45K20 anymore. Even though the MCP3204 only has 4 ADC channels and the PIC has 13, we do not need that many. For the MFC system we are testing with, it only has 4 MFCs on it. The chip interfaces with SPI and we were able to get readings from the chip. We are taking the average of 100 readings. The readings are off by a few mVolts. We have discussed it with our advisor, Dr. Kujoory, and he thinks it might be from the noise in the lab and/or the length of our wires.
Here is a reading from the program.
We have the voltage readings and are sending them to a text file and displaying the contents of it on the website. The program only does a finite amount of readings and won’t display the readings until the amount we set is finished. We want to be able to display the data all the time so the user doesn’t have wait for the program to finish executing.
Here is a table that is displayed on the website.
Our next stage, after we get better readings from the first relay,is to order more relays since we are only reading in one value in the MCP3204 chip, we want to read 4 values. We also want to get a Raspberry Pi 3 it should be faster than the Raspberry Pi B+ we currently have and it has built in Wi-Fi so we don’t need an adapter.
We also need to improve the website, right now it doesn’t display the readings in a graph. Jesse is going to look into it. We also need to have the website set up on an external server, that way you can be anywhere in the world and see the values from our system.