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hitsware2

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Joined: 03/08/2019
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Posted: 02:34am 29 Dec 2021

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OPTION SYSTEM SPI CLKpin, MOSIpin, MISOpin
Specify the SPI port and pins for use by system devices (SD card,LCD panel, etc).

SPI Based Display Panels
In all commands the (pin) parameters are:
DC = Display Data/Command control pin.
RESET = Display Reset pin (when pulled low).
CS = Display Chip Select pin.

Pins on my display :
D0, D1, RES, DC, CS

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TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6283

Posted: 04:42am 29 Dec 2021

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Not sure what you are asking but
D0 is DO = DataOut
D1 is DI = DataIn

The question remains, does Data Out connect to MOSI (Master OUT,Slave IN) or MISO?
Anyone's guess.

Jim

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hitsware2

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Posted: 05:01am 29 Dec 2021

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What ( I think ? ) I ' m asking :

The 2 ' option ' statements for a spi display
assign 6 pins ...
CLK , MISO , MOSI , DC , RESET , CS

BUT .... The display has 5 pins ....
DO , D1 , RESET , DC , CS

So 1 of the 5 pins must have 2 designations ....
Right ?

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phil99

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Joined: 11/02/2018
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Posts: 2642

Posted: 05:58am 29 Dec 2021

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I think DO = Data Out = MISO and DI= Data In = MOSI, it is that way on other panels. SPI requires a clock (CLK or SCK) so that might be DC (Data Clock?), still leaving it a pin short. The puzzle is that it is usually Chip Select (CS) that is optional not Data Command (D/C).

I guess you will have to search the web for a data sheet for your exact panel.

To work it out by non-destructive trial and error put 390R in series with each of the 5 display pins and try all combinations.

Found this showing that it is MISO that is missing and DO is the clock.

Edited 2021-12-29 16:17 by phil99

hitsware2

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Posted: 02:25pm 29 Dec 2021

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Yea .. I found that also ...
Hence perhaps DC=A0=MISO ?
and
The real question becomes ...
Is 1 pin# repeated in both
option system spi(CLK,MOSI,MISO)
and
option lcdpanel (DC,RESET,CS)....?(MISO,RESET,CS)?

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lizby
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Joined: 17/05/2016
Location: United States
Posts: 3378

Posted: 03:08pm 29 Dec 2021

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If the ssd1306sp can't be read from (e.g., with BLIT READ), then it doesn't need/use MISO. How the 'Mite configures the MISO signal should be irrelevant--it wouldn't be connected to the ssd1306sp. The absence of a MISO pin would seem to indicate that it's an input-only device.

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

hitsware2

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Posted: 06:54pm 29 Dec 2021

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lizby said If the ssd1306sp can't be read from (e.g., with BLIT READ), then it doesn't need/use MISO. How the 'Mite configures the MISO signal should be irrelevant--it wouldn't be connected to the ssd1306sp. The absence of a MISO pin would seem to indicate that it's an input-only device.

' so
option system spi clk,mosi, ' ? error without miso value

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lizby
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Posted: 06:56pm 29 Dec 2021

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You still need to specify the MISO pin, it just won't be connected to the SSD1306.

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

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