Add support for the Pimoroni Tufty 2040 #53
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boards/pimoroni-tufty2040/Cargo.toml
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| [features] | ||
| # This is the set of features we enable by default | ||
| default = ["boot2", "rt", "critical-section-impl", "rom-func-cache"] |
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tufty2040 is new enough that it should be safe to always enable rom-v2-intrinsics
| pins.lcd_rd.into_push_pull_output_in_state(PinState::High); | ||
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| /* | ||
| Example of using GPIO data lines: |
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Do you think anyone will use these pins as GPIO?
If so, it would be better to document this use-case elsewhere, not in an example.
I think everyone will use your PIO+DMA driver and never touch the display pins directly.
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Fair question - it was useful to me whilst getting everything working, but given just the built-in peripherals I don't know that anyone would choose to avoid the PIO unit & DMA channel.
Do you want me to consign the GpioDataLines implementation to history? (If I leave the DisplayDataLines trait, it's easy enough to implement out-of-tree.)
| .program st7789_parallel | ||
| .side_set 1 | ||
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| out pins, 32 side 0 |
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there's only 8 LCD data pins, why specify 32 here?
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Judging by the datasheet, the shift register is always filled by 32-bits and since we're using DMA to write a byte at a time, we want to clear the whole thing.
Also improve the description of the demo.
* Add support for Tufty 2040 * Rename tufty_blinky to tufty_demo Also improve the description of the demo. * Enable rom-intrinsics-v2 by default on tufty2040
This includes pin numbering and bindings to the ST7789 display.
There is one pretty painful issue: DMA is generally not used for
embedded_graphicscommands, since most commands are generated via an iterator. (This is particularly noticeable at startup, as the st7789 library turns the display on without leaving time for us to clear the screen buffer, which takes a while without DMA.)However, I don't feel that solving that issue is under the remit of
rp2040-hal. Ideallyst7789could do with hooks to allow DMA for long copy operations and itsinit()function needs to be broken up.