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The main motivation to get Forth up and running on the Steckschwein was to participate at The Ultimate Benchmark, in order to crush all 8bit competition to dust.

So the plan was to benchmark the Steckschwein live at the VCFe. Unfortunately, Carsten could not be there, so no Forth benchmark competition this year. Recently, Carsten presented his benchmark results using TaliForth2, which led us to run the same benchmarks he did and send the results to Carsten, who was kind enough to include them on his site:

As real computer is not a real computer without a real time clock, the Steckschwein is no exception here. As we know, we use the Maxim DS1306 RTC, which is a very common RTC which comes as DIP IC and has an SPI interface. And of course it supports battery backup in various configurations. And this is where things get interesting.

Apart from timekeeping, the DS1306 also has 96 bytes of battery buffered RAM. The ideal place to store system configuration parameters. As of now, the RTC NVRAM contains the name of the file to be read from sdcard at startup, the line parameters for the serial interface (baud rate, data bits, parity, stopbits), and also a version number and a crc7 checksum:

The Tekway DST 1062B (also known unter the Hantek or Voltcraft brand) is an inexpensive 60MHz digital storage oscilloscope, which is very much hackable and has proven to be worth its weight in gold pressed latinum.

More recently, my scope became affected by the infamous white screen problem, which apparently is a problem quite common to this model and its 100MHz or 200MHz siblings.

The Tekway/Hantek white screen of death

The newly made boards made their way from China to Munich. Starting now, the multi board version of the Steckschwein is made up of 3 Boards: CPU/Memory, IO/UART and V9958-OPL2.

It’s time for another hardware upgrade. Since we really want to get our single board Steckschwein done, we are going for higher integration of our multiboard prototype. After integrating the UART to the IO-Board, we integrate the OPL2 sound part onto the V9958 video board, so the current Steckschwein multi board incarnations are reduced to three boards. We did postpone our plan to upgrade sound to OPL3 because Daniel Illgen, which we met at VCFb, convinced us with some awesome OPL2 tunes that OPL2 is still cool. Also, we save the extra oscillator, since the OPL2 can be clocked using the CPUCLK-Pin from the V9958, which happens to provide 3.58MHz.

… on the way back to munich, we had some time to do a little code review of our gfx library. thinking about the cpu to video chip timings and again read the well known datasheets of the V9938/V9958. suddenly i got an enlightenment and we came to the following conclusion.

as described in the datasheet (V9958-Technical-manual_v1.0.pdf) of the V9958 there are different timings given for different kind of writes. so as far as we understand there are the following timings