diff options
| author | Javier Degirolmo | 2013-04-22 05:30:00 -0300 |
|---|---|---|
| committer | Javier Degirolmo | 2013-04-22 05:30:00 -0300 |
| commit | eecc39834949e6affbf3268cb5405a296cd12216 (patch) | |
| tree | d97fa90e4610ccc1afc52cf88b8db27b034ef3d4 /doc/api-asm.68k | |
| parent | 40459d3587f607753dd2f5036d2b2471cdf23add (diff) | |
Now you can change the sample rate of PCM instruments
Diffstat (limited to 'doc/api-asm.68k')
| -rw-r--r-- | doc/api-asm.68k | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/doc/api-asm.68k b/doc/api-asm.68k index e6f466c..ad552f3 100644 --- a/doc/api-asm.68k +++ b/doc/api-asm.68k @@ -88,6 +88,31 @@ Echo_GetStatus ============================================================================= +*** Settings *** + +Echo_SetPCMRate + + Changes the sample rate of PCM. Note this is a global parameter as it + affects both BGM and SFX. The value is what one would write in timer A of + the YM2612 register. Here are the approximate frequencies for some values + (default is $05): + + NTSC PAL | NTSC PAL + ----------------------------|-------------------------- + $02 ... 26632Hz ... 26389Hz | $08 ... 6658Hz ... 6597Hz + $03 ... 17755Hz ... 17593Hz | $09 ... 5918Hz ... 5864Hz + $04 ... 13316Hz ... 13194Hz | $0A ... 5326Hz ... 5278Hz + $05 ... 10653Hz ... 10556Hz | $0B ... 4842Hz ... 4798Hz + $06 .... 8877Hz .... 8796Hz | $0C ... 4439Hz ... 4398Hz + $07 .... 7609Hz .... 7539Hz | $0D ... 4097Hz ... 4060Hz + + The higher the sample rate, the better quality, but also takes up more + space and, more importantly, reduces CPU time available for other things + (which can hamper Echo's ability to process complex streams). Be careful + if you increase the sample rate. + +============================================================================= + *** Raw access *** Echo_SendCommand @@ -95,10 +120,16 @@ Echo_SendCommand Sends an argument-less command to Echo. The command ID is given as a byte in register d0. -Echo_SendCommandEx +Echo_SendCommandAddr Sends a command to Echo that takes an address as its argument. The command ID is given as a byte in register d0, while the address argument is given in register a0. +Echo_SendCommandByte + + Sends a command to Echo that takes a byte as its argument. The command ID + is given as a byte in register d0, while the byte argument is given in + register d1. + ============================================================================= |