Add fast transfer rate for the Pico/RP2040

[zapta]

Hello Bodmer,

The Pico/RP2040 contains Programmable IO (PIO) units that allow a very fast data transfer to the TFT with 8 or 16 bits parallel paths. For example, the proof of concept in the repository below uses a small PIO program and a 8 bit parallel path transfer 30MB/s or 15M pixels/sec This an equivalent of > 240Mbps for a SPI interface.

https://github.com/zapta/pio_tft/blob/main/platformio/src/pio_tft.cpp

Is this something that you would like to add to TFT_eSPI? If so, if you can specified the expected API from the low level PIO driver, I can implement it. The current version of the API is at https://github.com/zapta/pio_tft/blob/main/platformio/src/pio_tft.h

The PIO program is at https://github.com/zapta/pio_tft/blob/main/platformio/src/pio_tft.pio . The assignment of the DB0-7, WR, DC, RST, BL, and CS pins is arbitrary, the only requirements is that DB0-DB7 will be consecutive RP2040 gpio pins.

[Bodmer]

Hello Zapta,
Thank you for the PIO code, I have incorporated it into a test branch and it is working well:
https://github.com/Bodmer/TFT_eSPI/tree/RP2040_8bit_parallel
Typical results for the "graphicstest" sketch on a 320 x 480 ILI9488 screen:

Benchmark,                Time (microseconds)
Screen fill (5 times),    49711  (100.58 fps)
Text,                     7893
Lines,                    83295
Horiz/Vert Lines,         4349
Rectangles (outline),     2724
Rectangles (filled),      121211
Circles (filled),         29576
Circles (outline),        28686
Triangles (outline),      18275
Triangles (filled),       53626
Rounded rects (outline),  11216
Rounded rects (filled),   126054
Total = 536616us
Total = 0.5366s

[zapta]

Great. Thanks Bodmer!

…

On Thu, Dec 16, 2021 at 8:42 AM Bodmer ***@***.***> wrote: Hello Zapta, Thank you for the PIO code, I have incorporated it into a test branch and it is working well: https://github.com/Bodmer/TFT_eSPI/tree/RP2040_8bit_parallel Typical results for the "graphicstest" sketch on a 320 x 480 ILI9488 screen: Benchmark, Time (microseconds) Screen fill (5 times), 49711 (100.58 fps) Text, 7893 Lines, 83295 Horiz/Vert Lines, 4349 Rectangles (outline), 2724 Rectangles (filled), 121211 Circles (filled), 29576 Circles (outline), 28686 Triangles (outline), 18275 Triangles (filled), 53626 Rounded rects (outline), 11216 Rounded rects (filled), 126054 Total = 536616us Total = 0.5366s — Reply to this email directly, view it on GitHub <#1227 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAQVMQN545CPJGWFU4JKBJTURIJHBANCNFSM46GXNBOA> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>. You are receiving this because you authored the thread.Message ID: ***@***.***>