| 0,0 → 1,57 |
|---|
| /* |
| * SoundBlaster routines for DSP driving |
| * |
| * Copyright (C) 2022 Mateusz Viste |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to |
| * deal in the Software without restriction, including without limitation the |
| * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or |
| * sell copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| * IN THE SOFTWARE. |
| */ |
| |
| #ifndef MDR_SBDIGI_H |
| #define MDR_SBDIGI_H |
| |
| struct sbdigi_ctx; |
| |
| /* initializes the SoundBlaster DSP chip |
| * blaster must point to a BLASTER environment string (like "A220 I5 D1") |
| * returns a pointer to a context, NULL on error |
| * NOTE: DSP's state after initialization may or may not be muted, depending |
| * on the exact hardware revision. use sbdigi_spkoff() to make sure it is |
| * unmuted */ |
| struct sbdigi_ctx *sbdigi_init(const char *blaster); |
| |
| /* unmutes the SoundBlaster DSP */ |
| void sbdigi_spkon(struct sbdigi_ctx *ctx); |
| |
| /* mutes the SoundBlaster DSP */ |
| void sbdigi_spkoff(struct sbdigi_ctx *ctx); |
| |
| /* plays a short sample |
| * ctx - DSP context, as returned by sbdigi_init() |
| * buf - pointer to sample data (must be PCM, 8000 Hz, mono, 8-bit unsigned |
| * len - length of the sample, in bytes |
| * NOTES: this routine uses DMA to transfer memory. This has two implications: |
| * 1. the routine will return almost immediately, while the sound is playing |
| * 2. sample data must be contained in a buffer that does NOT cross a 64K page |
| * because DMA transfers are unable to cross 64K boundaries */ |
| void sbdigi_playsample(struct sbdigi_ctx *ctx, void *buf, unsigned short len); |
| |
| /* shuts down the DSP and frees context memory */ |
| void sbdigi_quit(struct sbdigi_ctx *ctx); |
| |
| #endif |