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Ok, so it has been a few days since I etched my prototype Jaguar PCB and I felt like I should share what I have been up to

I have drilled out the PCB for the through hole components and run the PCB through a reflow soldering cycle in my Wally World special toaster oven to install the Freescale 112pin MCU, the FT232RL USB-Serial converter and the opto-isolators.

Attached are some photos I snapped during the reflow cycle and of both sides of the PCB during testing.

Notice that the optos are missing in the SMT photo, I was having a problem with it communicating between the FT232RL and the MCU so I removed the optos and the associated resistors to make sure it would work without them in the circuit.

At this point it communicates flawlessly with MTX and I am able to flash firmware with both Sean's freeems-loader and the MTX loader, so now I just need to figure out the problem I had with the optos (data was getting corrupted between the FT232RL and the MCU).

More to come, stay tuned...

Cool! Any chance of posting the details of your oven setup? :-)

Grumpy wrote:Cool! Any chance of posting the details of your oven setup?

Sure, I have schematics and source code for a PIC16F88 as well that is GPL and tailored for lead-free solder

I will create a thread in Soldered for the oven details and sync the files to my github repository later on tonight...

Mostly curious about the sensor, heater driver and oven itself, but the more the merrier :-) I intend to write my own code and have a different micro in mind ;-)

I used a Type-K thermocouple with a Maxim chip (I don't recall which one at the moment and the files are on the computer at home, but I will follow up later tonight) and I used a 5vdc coil/12A@240vac relay to switch current on/off to the heating elements. The oven was a Black & Decker 1000 watt 2 element version. It can run the cycle within a few degrees per second of the specifications for the lead-free solder paste I'm using, which is also within the temperature specs of the ICs I am using.

I will post complete details later this evening.

Yep very cool,and man do you move fast
Keep up the good work

keep up the good work!

I am curious to know what is wrong with the optos ? can you post up about them when you sort it out please? you used the RavAGE schematics for them didnt you?

Dan: I used the same circuit and part # for the opto protection as you had drawn for your Ravage project. I will add them back to the circuit this evening and report back as soon as I have more information...

DeuceEFI wrote:Dan: I used the same circuit and part # for the opto protection as you had drawn for your Ravage project.

I have very, very, little experience with opto-couplers, but after taking a quick look at the data sheet for this part, it looks like the load resistor has a very large impact on the bandwidth + it looks like the opto is supposed to be used in a voltage follower configuration (high to the input, anode of the LED, drives a high on the output, transistor sources from Vcc). At least from my quick, unknowledgeable interpretation of the data sheet, with a 10k load resistor, bandwidth is pretty low. Is there any history of this circuit working before?
Thanks,
Huff

Huff: This is the first time I have tried to use these optos with the FT232R chip so at least for me personally I'm trying to learn if this will work for our application...

I put the optos back in the circuit as drawn in the Ravage and Jaguar schematics but all I get out as seen by cutecom is all 0 (zeroes) and MTX will not see it as a FreeEMS board. If I remove the optos from the circuit along with the accompanying resistors then MTX can see it as a FreeEMS board and function correctly. I will try using the circuit from the data sheet on my protoboard to see if the results are different.

I will let you know how it works after changing the circuit.