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Cleaned up grammar, mostly 

Might need some changes after this considering some lines were rather confusing - I don't actually know much about how this chip works exactly
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# Seta/Allumer X1-010
One of sound chip originally designed by Seta, mainly used at their arcade hardwares at late-80s to early-2000s.
It has 2 output channels, but no known hardware using this feature for stereo sound.
A sound chip designed by Seta, mainly used in their own arcade hardware from the late 80s to the early 2000s.
It has 2 output channels, but there is no known hardware taking advantage of stereo sound capabilities.
Later hardware paired this with external bankswitching logic, but this isn't emulated yet.
Allumer one is just rebadged Seta's thing for use in their arcade hardwares.
Allumer rebadged it for their own arcade hardware.
It has 16 channels, and all channels can be switchable to PCM sample or wavetable playback mode.
Wavetable needs to paired with envelope, this feature is similar as AY PSG, but its shape are stored at RAM: it means it is user-definable.
It has 16 channels, which can all be switched between PCM sample or wavetable playback mode.
Wavetable playback needs to paired with envelope, similar to AY PSG, but shapes are stored in RAM and as such are user-definable.
In furnace, this chip is can be configurable for original arcade mono output or stereo output - it simulates early 'incorrect' emulation on some mono hardware, but it is also based on the assumption that each channel is connected to each output.
In furnace, this chip can be configured for original arcade mono output or stereo output - it simulates early 'incorrect' emulation on some mono hardware, but it is also based on the assumption that each channel is connected to each output.
# waveform type
# waveform types
This chip supports 2 type waveforms, needs to paired external 8 KB RAM for use these features:
This chip supports 2 types of waveforms, needs to be paired to external 8 KB RAM to access these features:
One is signed 8 bit mono waveform, it's operated like other wavetable based sound systems.
These are stored at the bottom half of RAM at common case.
One is a signed 8 bit mono waveform, operated like other wavetable based sound systems.
These are stored at the lower half of RAM at common case.
Another one ("Envelope") is 4 bit stereo waveform, it's multiplied with above and calculates final output, Each nibble is used for each output channels.
The other one ("Envelope") is a 4 bit stereo waveform, multiplied with the above and calculates final output, each nibble is used for each output channel.
These are stored at the upper half of RAM at common case.
Both waveforms are 128 byte fixed size, it's freely allocated at each half of RAM except channel register area: each half can be stored total 32/31 waveforms at once.
In furnace, You can set envelope shape split mode. When it sets, its waveform will be split to left half and right half for each outputs. each max size are 128 bytes, total 256 bytes.
Both waveforms are 128 bytes (fixed size), freely allocated at each half of RAM except the channel register area: each half can store total 32/31 waveforms at once.
In furnace, you can enable the envelope shape split mode. When it is set, its waveform will be split to the left and right halves for each output. Each max size is 128 bytes, total 256 bytes.
# effects
@ -31,8 +31,8 @@ In furnace, You can set envelope shape split mode. When it sets, its waveform wi
- `20xx`: set PCM frequency (1 to FF).
- `22xx`: set envelope mode.
- bit 0 sets whether envelope will affect this channel.
- bit 1 sets whether envelope one-shot mode. when it sets, channel is halted after envelope cycle is ended.
- bit 2 sets whether envelope shape split mode. when it sets, envelope shape will splitted to left half and right half.
- bit 1 toggles the envelope one-shot mode. when it is set, channel is halted after envelope cycle is finished.
- bit 2 toggles the envelope shape split mode. when it is set, envelope shape will be split to left half and right half.
- bit 3/5 sets whether the right/left shape will mirror the original one.
- bit 4/6 sets whether the right/left output will mirror the original one.
- `23xx`: set envelope period.