Sunday, February 11, 2018

Super Nt Review - The Ideal FPGA Console?

In the four months since the announcement of the Super Nt, there has been a lot of anticipation over the final product.  Will it ship on time?  Will it be as good as the Nt Mini?  Is it worth the money?  Can I put my original hardware away?  Now that I have had mine for about four days by the time this blog entry posts, I can try to answer those questions and give my own impressions of the system.

Sunday, February 4, 2018

StarTech USB3HDCAP Review - A Jack of All Trades?

The StarTech USB3HDCAP (courtesy of
Capturing real hardware has always been something of a challenge, especially when it comes to retro video game consoles and computers.  I have been seeking an affordable "all-in-one" capturing solution for some time.  Recently I read about the StarTech USB3HDCAP and remarked that it could handle odd inputs like 15KHz RGB, 240p Component video and even 320x200 70Hz VGA.  I also read that the StarTech uses the same hardware as the more expensive Micomsoft X-CAPTURE 1 and the less-featured Elgato HD60 S.  I purchased a card recently and found that getting the best out of it is not quite as straightforward as I expected.  Here let me discuss what I have tried and how well it works.

Wednesday, January 24, 2018

sd2snes and MSU-1

The MSU-1 was a software memory controller (mapper) created by byuu for the bsnes/higan emulator to allow for vastly increased storage for SNES software.  The MSU-1 allows for ROMS up to 4GB in size whereas ROMs for the SNES were limited usually to 4MB without extra hardware.  FMV playback became possible due to the DVD-like storage capacity provided by the MSU-1.  In addition to the size increase, the MSU-1 allows for streaming audio in the same format provided by a CD, namely 16-bit uncompressed stereo audio at a 44.1KHz sample rate.  The ill-fated SNES CD-ROM system that Nintendo and Sony collaborated on was not nearly as powerful and would have suffered from noticeable load times.  In this blog post, let's talk about the hardware behind the MSU-1 and some of the more interesting hacks available for it.

Wednesday, January 10, 2018

Famicom & NES - Simple Tweaks to Restore Audio Balance Levels

Audio balance levels in the NES and Famicom can cause some consternation and official hardware is not always consistent.  Here I will discuss some simple modifications you can do to your console to restore the balance between internal audio channels and internal audio channels and external cartridge audio.

Sunday, January 7, 2018

Analogue Nt Mini : Audio Tweaking

The Nt Mini's audio has come under some criticism from such luminaries as the My Life in Gaming channel.  Kevtris has fixed NES audio issues in Jailbreak firmwares v1.0 (MMC5 pulse pitch), v1.3 (audio sweep bug), and v1.8 (crackling static issue).  The excellent MLiG video was using v1.2, so its statements may not hold true for the latest official or jailbroken firmware.  Even so, it is hard to diagnose and fix a problem without being able to define the problem or demonstrate it in a way that would illustrate the problem to the less-technical viewer.  The MLiG video said little more than "We feel that sound might be somewhat further removed from the original hardware experience than any other aspect of the system."  

That MLiG comment is so vague as to suggest that the Nt Mini could be outputting reversed-duty cycle pulse waves like a Famiclone or too low pitched noise as with the NES Classic Edition, which it clearly does not.  Nonetheless, a more articulate critic of kevtris' APU implementation in the Nt Mini and Hi-Def NES Mod is that in certain musical tracks, the triangle and noise channels are too quiet compared to the two pulse channels.  In order to talk about this claim, first we must discuss the mixing levels of NES APU channels.

Friday, January 5, 2018

OPL2/3 Frequency - The 1Hz-ish Difference

The nature of FM Synthesis sound is based on sine waves.  Sine waves create sound by oscillating at a certain frequency and amplitude.  So a sine wave oscillating at a frequency of 440Hz (the pitch) would sound like an A note (A4) hit above the middle C (C4) on the 4th octave of a full 88-key keyboard.  But a sine wave in and of itself is not very interesting musically, so FM synthesis modulates two or more sine waves to create a much more complex sound.  The sine wave's frequency is programmed into the FM Synthesis chip and the modulation of the two frequency, combined with other methods to shape the waveform such as ASDR envelopes, make a sound more complex and realistic than the Programmable Sound Generators that were used in computer and video game music before FM Synthesis became popular in computer music.

Monday, January 1, 2018

Hyperkin's SNES Mouse - A Curious Product out of Left Field

In the middle of 2017, one of the more prominent companies that make retro-video gaming products, Hyperkin, announced a new mouse for the SNES.  The SNES mouse was released with Mario Paint in 1992, and while some other games supported it, it was mainly associated with Mario Paint.  Needless to say this announcement came as something of a surprise, as few people were really clamoring for a replacement SNES mouse.  I was so fascinated by this product that I resolved to obtain one as soon as I could, budget permitting, and review it on this blog.  This Christmas, the budget did permit my acquisition of what Hyperkin calls the "Hyper Click Retro Style Mouse for SNES", so let us proceed to the review.

Friday, December 22, 2017

Parallel & Serial Sound Card Emulation Options for your Vintage PC

In the beginning the Intel 8088 and 8086 CPUs only implemented, Real Mode, where a program had total control over all aspects of a system.  Real Mode's main issue, other than it was limited to 1MB of RAM, was that multitasking was almost impossible to accomplish.  Then the 286 CPU implemented a Protected Mode and allowed the CPU to address 16MB in that Mode, but few applications used it because DOS required Real Mode. Finally, the 386 CPU implemented a far more usable Protected Mode and a Virtual 8086 Mode (V86).  V86 Mode allowed the CPU to run multiple instances of Real Mode where each program would be given access to up to 1MB of RAM for their own purposes without overwriting another program's data.  To each program running in V86 Mode, it would appear to it as though it had full control over the PC.

As a byproduct of V86 Mode, Expanded Memory, which had been implemented with expansion cards on 8088 & 286 machines, could be emulated with Expanded Memory Managers (EMS).  The most popular EMS was EMS386, which came with MS-DOS 5.0 and later.  There were other EMS softwares like QEMM and JEMM.  EMS also allowed a user to trap writes to memory locations and I/O ports.  Sound cards invariably wrote to I/O ports on a PC to make sound.  Eventually it was discovered that this port trapping capability could be used to emulate sound cards.  Software drivers of recent and ancient vintage have been being this feature, or implementing their own, to emulate sound cards and chips for systems that may not or cannot use them.  Let's take a look at some of these devices and methods.