Building the TerribleFire TF530r2, Part 2: Obtaining the components
So I've made the descision to try to build a TerribleFire TF530r2 accelerator. The TF530 uses SMD components, which are really small, but the overall number of components is quite low. Based on that, I decided that with good eyesight and accepting some fail-rate it should generally be possible to build the thing.
Disclaimer: This is not an instruction. Use at your own risk. No responsibility taken for whatever you do. Safety first. Kids, dont try this at home.
Parts and cost
As we know, the docs of the TF530 can be found at: https://github.com/terriblefire/tf530
The readme file contains a BOM (bill of material), of which columns 2 to 4 are relvant for component indentification. It takes some time to get used to specifications and naming. When looking for parts, keep an eye on the "Package" (column 4 of BOM), which in some cases describes the required type (shape/layout/...). Also sometimes you will find out there are variations of components, like for industrial use, made of different material, etc., which are identified by some suffix appended to the name given in the BOM. Finding the matching socket for the 68030 CPU can also be a bit tedious, it has a special layout.
And of course there's the PCB (circuit board) itself, which you can order from dirtypcbs.com: http://dirtypcbs.com/store/details/1330/tf530-rev2b-zip
After hours of searching the internet, I got this impression:
- the PCBs are really cheap
- parts are generally available
- some parts seem to be a bit rare and can only be ordered from one or two retailers
- few parts are cost relevant: CPU, FPU, sockets for CPU and FPU, and SRAM
- the socket / connector to the Amiga's original CPU socket is a critical part that's rare, thus comparably expensive
I decided to go with a 40MHZ 68030RC CPU, 40MHz 68882 FPU, and will not use industrial parts, which cost more and are probably more reliable, but I'm assuming there are no extreme temperatures etc. on the TF530. For the 68000-socket connector I'll try to modifiy some other pin connector (2.54mm pin grid).
It turns out that including shipment from different retailers we're still in the "around 100EUR" range for a complete accelerator board, which is an acceptable risk.
So I placed my orders.
TF530r2 PCB (circuit board) from dirtypcbs.com:
You probably want to order a "Protopack (+/-10)" which is the cheapest option, and gives you (about? +/-?) 10 boards to play with.
68030 CPUs and 68881 or 68882 FPUs are available on eBay.
Additionally, I ordered one or two individual parts via eBay directly from China if there was a good offer.
Special thanks to the very friendly and helpful guy at CONRAD store (Munich, Moosach) who recommended to buy a soldering station and gave lots of information, you're doing a fantastic job!
Delivery & Conclusion
The overall time spent on obtaining the parts has to be somewhere around 20hrs, for research, talk, orders, and purchases at local stores. 10 weeks went by from placing the first order to receiving the last one.
Everything arrived properly packaged, and hopefully it's the correct parts... I'll just have to trust them on this. ;-)
Blue TF530r2 PCBs look great, my "protopack (+/-10)" contained ten pieces. On first visual inspection one of them that has a tiny flaw between two IC soldering pads - maybe that's the "Protopack (+/-10)" option? Less quality control than ordering "10" (pieces)? I'll be using that flawed one for some SMD-soldering warm-up practice.
Overall I had one or two issues with the ordering process, but I'm pleasantly surprised how well everything worked, including resolving these issues.
Next time we'll see what we've missed so far, and be doing our first soldering tests - watch out for part 3 of our series "Building the TerribleFire TF530 accelerator board"!