Cerebot 32MX4 and mpide

Created Wed, 21 Nov 2012 23:08:22 +0000 by danm3030

danm3030

Wed, 21 Nov 2012 23:08:22 +0000

Hi, I recently bought the uC32, which is really really nice, and started using it with mpide.

I notice mpide also has a selection for the old 32MX4 board, which I have had for a couple of years. The board works with MPLAB 8.86, and appears properly there as a PIC32 Starter kit, when the proper driver is loaded.

However, the 32MX4 does not seem to show up on the mpide in the "Tools > SerialPort" menu. I've tried all 3 USB connectors on the 32MX4, and also selecting the Board as 32MX4 and also PIC32 Start kit.

Can you direct me in the proper direction on this.

Also, it is possible to download the bootloader used in the 32MX4ck into the 32MX4 board. I do have a PICKIT3.

Thanks.

mkirby

Mon, 17 Dec 2012 21:33:26 +0000

Yes you can use the MX4cK bootloader for this board. Really the only difference between these two boards is the extra UART USB header on the MX4cK. The 32mx4 does not have this header so you will not be able to simply plug in a USB cable from the board to your computer to use with MPIDE. You will need to use something like an RS232x pmod and an RS232->USB cable to go from UART->RS232->USB type signaling. Using this on the pmod port that is attached to the UART 1 controller will then allow you to use this board with MPIDE.

KeithV

Thu, 20 Dec 2012 17:16:30 +0000

This is deceptively complex to do; but is possible. There are 2 ways to do it, neither is particularly satisfying.

The first is to do (almost) exactly as Michael Kirby says and use a pmodUSBUART Serial Converter and plug that into the top 6 pins on connector JE. But here is the rub, the 32MX4 uses an obsolete UART pin out and you will also need to purchase a cross-over cable to convert the new UART pin out to the old one used on the 32MX4. You can read about this complication at:

http://www.digilentinc.com/Data/Documents/Other/Connecting%20UART%20Pmod%20Interfaces.pdf

What you would need to get is a cross-over cable and the pmodUSBUART

http://www.digilentinc.com/Products/Catalog.cfm?NavPath=2,393&Cat=3 (scroll down to the UART Crossover Cable) http://www.digilentinc.com/Products/Detail.cfm?NavPath=2,401,928&Prod=PMOD-USB-UART

However, when you hook this up, MPIDE will NOT auto reset the board when uploading a sketch, so you will have to “quickly” power off and then on the 32MX4 (as there is no reset button on the board) and then within the 2 seconds or so that the bootloader is listening for the upload, get MPIDE to upload the sketch. It is difficult to hit that timing as the bootloader only gives you a 2 second window (remember, the bootloader thinks MPIDE is going to control the reset).

With the 32MX4 you need to treat this board as a chipKIT board without auto-reset capabilities from MPIDE, that is, you need to have a program button. I have made a skunk project bootloader for the 32MX4 that will assign button 1 on the board as a program button. The way this works is, if you hold the program button as you power cycle the board, when the 32MX4 comes up it will stay in the listening mode until you upload a sketch from MPIDE. If you do not press the program button as you cycle the power, the bootloader will just load the previously program sketch and run that. I have attached a .zip file with this bootloader in it if you want it.

However, there is another way to go that requires no new hardware; but this also has its limitations. You can use the USB port on the 32MX4 (not the debug USB, the Device USB) if you have a USB bootloader for it. I have also made such a skunk project bootloader, it is also in the attached zip file. While this requires no additional hardware, you will NOT be able to use the serial monitor once your sketch is running. Again, a lot of complications here as to why, but there is (and will be fixed in the next official release of MPIDE) a bug in the USB for Serial code in the MPIDE runtime and for that reason the 32MX4 is defined to NOT use USB for Serial for the serial monitor. So even if you can program your sketch via the USB bootloader, you won’t be able to use the serial monitor from your sketch. As with the other bootloader, you will need to hold button 1 as you power cycle the 32MX4 to put the bootloader into listening mode on the USB; remember, no auto-reset from MPIDE and you need to have a program button (btn 1). Also make sure the serial monitor is NOT displayed when you put the 32MX4 into listening mode as the serial port will not show up in MPIDE if the serial monitor window is displayed. Also be aware, once you upload a sketch via the USB, the serial port will disappear in MPIDE as the bootloader closes the USB when done.

Eventually we will probably go back to making the 32MX4 a USB for Serial board once a fixed MPIDE is posted; and then you will be able to use the serial monitor from your sketch over the USB.

Oh, BTW: if you use the UART solution above, you CAN use the serial monitor as that doesn’t use the USB for Serial code in MPIDE.

Hope this helps; and good luck.

pr0ton

Mon, 12 Jan 2015 16:47:59 +0000

Hi, whenever I download the zip file it says it's corruped when opening. I would like to try to make it work without any additional hardware on my old 32MX4. Thanks!!

pr0ton

Tue, 27 Jan 2015 17:34:49 +0000

Test: can i reply now, lost my post it seems.