Difference between revisions of "MTX Registers"
(Document more matrix unit bits) |
(Update MTX bits and interrupts) |
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| 0x1EC1x00C | | 0x1EC1x00C | ||
| − | | | + | | [[#MTX_IE|MTX_IE]] |
| 4 | | 4 | ||
|- | |- | ||
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|- | |- | ||
| 0 | | 0 | ||
| − | | Enable bit | + | | Enable bit |
|- | |- | ||
| 1 | | 1 | ||
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|- | |- | ||
| 15 | | 15 | ||
| − | | | + | | Start bit (setting this will eventually raise MTX interrupt 0) |
|- | |- | ||
| 16 | | 16 | ||
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Reading this register will return pending interrupts. | Reading this register will return pending interrupts. | ||
| − | Writing this register will acknowledge the | + | Writing this register will acknowledge pending interrupts where the bits are set. |
{| class="wikitable" border="1" | {| class="wikitable" border="1" | ||
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|- | |- | ||
| 0 | | 0 | ||
| − | | | + | | FIFO ready (signal to start DMA) |
|- | |- | ||
| 1 | | 1 | ||
| − | | | + | | FIFO overrun(?) (occurs if DMA is too slow) |
|- | |- | ||
| 2 | | 2 | ||
| − | | | + | | FIFO underrun(?) (occurs on VBlank) |
|- | |- | ||
|} | |} | ||
| + | |||
| + | ==MTX_IE== | ||
| + | |||
| + | Interrupt Enable for the above interrupts. | ||
Latest revision as of 00:07, 2 April 2020
These registers are responsible for controlling how framebuffer data can be DMA'd from the DS GPU, and also for configuring the upscaling matrix.
Registers[edit]
The physical address can be calculated by subtracting 0xEB00000 from the virtual address.
Control[edit]
| VAddress | Name | Width |
|---|---|---|
| 0x1EC1x000 | MTX_CNT | 4 |
| 0x1EC1x004 | MTX_SIZE | 4 |
| 0x1EC1x008 | MTX_ACK | 4 |
| 0x1EC1x00C | MTX_IE | 4 |
| 0x1EC1x020 | ??? | 4 |
Matrix unit[edit]
There are two matrix units, one at +0x200 for vertical (Y) scaling, and the other one at +0x300 for horizontal (X) scaling.
| VAddress | Name | Width | Description |
|---|---|---|---|
| 0x1EC1xn00 | KRN_WIDTH | 4 | Kernel width - 1 is written here, 1 <= width <= 8
This decides how many pixels are written each batch. |
| 0x1EC1xn04 | KRN_PATTERN_BITS | 4 | If the corresponding bit for the current batch iteration index is set then a new pixel is read.
The amount of set bits determine how many pixels are read each batch. Any bit indexes past KRN_WIDTH are ignored. This value is 8 bits, but it has to be written with a 32bit write. |
| 0x1EC1xn40 | KRN_MTX | 0xC0 | int kerneldata[6][8]; - matrix data is written here, height is always 6 |
Descriptions[edit]
MTX_CNT[edit]
| Bit(s) | Description |
|---|---|
| 0 | Enable bit |
| 1 | Enable vertical matrix |
| 2 | Enable horizontal matrix |
| 4 | ??? |
| 5 | ??? |
| 8-9 | Input pixel mode? 0 = 4byte color, 1 = 3byte color, 2 = 2byte color, 3 = 2byte color |
| 10-11 | Output framebuffer rotation: 0 = normal, 1 = 90° CW (right), 2 = 180° CW (upside down, not mirrored), 3 = 270° CW (left) |
| 12 | Output tiling for use with the GPU. When set, the output width and height must be a multiple of 8. |
| 15 | Start bit (setting this will eventually raise MTX interrupt 0) |
| 16 | Data still available flag (?) |
MTX_SIZE[edit]
| Bit(s) | Description |
|---|---|
| 0-8 | Output framebuffer width - 1 is written here, 1 <= width <= 512 |
| 16-25 | Output framebuffer height - 1 is written here, 1 <= height <= 512 |
MTX_ACK[edit]
Reading this register will return pending interrupts. Writing this register will acknowledge pending interrupts where the bits are set.
| Bit(s) | Description |
|---|---|
| 0 | FIFO ready (signal to start DMA) |
| 1 | FIFO overrun(?) (occurs if DMA is too slow) |
| 2 | FIFO underrun(?) (occurs on VBlank) |
MTX_IE[edit]
Interrupt Enable for the above interrupts.