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.

Saturday, December 9, 2017

Analogue Nt Mini : Browsing the Core Store Pt 2, AV and Future Predictions

In what is likely to be the penultimate article in my Analogue Nt Mini series for some time I intend to devote some time to a few of the more interesting cores remaining in the system, then discuss the video output from the NES.  Finally, I will offer my predictions for the future.

Saturday, December 2, 2017

Atari Flashback 2 - The Only Flashback Worth Anything

While browsing in one of my local thrift stores, I encountered an item I had been wanting for a long time, the Atari Flashback 2.  This mini-console with its built in games had interested me ever since it first game out.  Even though I already had a light-sixer 2600 and a Harmony Cartridge, I still wanted one of these.  The box was marked at $24.99, but the seal seemed to be still intact, so the purchase was a no-brainer for me.  In this blog post, let me describe the system, its capabilities and talk about its included games and its legacy.  This review may be 12 years too late, but I could not let this opportunity pass without comment.

Sunday, November 5, 2017

Analogue Nt Mini - Vs. System Support

Originally I was going to post a conclusion to my Analogue Nt series, but then I had an epiphany that was too long to attach to one of the prior posts.  Yesterday I was thinking about the Nintendo Vs. System and lack of comprehensive hacks available for the games that were released for that system.  I wondered if it was possible, given the Nt Mini's extraordinary capabilities, to get the pure Vs. System ROMs running on the system through its Flashcart functionality.  About six hours of testing later, I think can present a solution that can get many of these games working now.