I2C frequency gets narrowed

[ggatis]

Display works with default constructor. Error using custom I2C frequency: DisplaySH1107_64x128_I2C display( -1, { -1, 0x3C -1, -1, 1000000 } );

lcdgfx_sh1107_demo:46:68: error: narrowing conversion of '1000000' from 'long int' to 'int8_t {aka signed char}' inside { } [-Wnarrowing] DisplaySH1107_64x128_I2C display( -1, { -1, 0x3C -1, -1, 1000000 } ); ^ Using library lcdgfx at version 1.1.4 in folder: ...\Arduino\libraries\lcdgfx Using library SPI at version 1.0 in folder: ...\ArduinoData\packages\lgt8fx\hardware\avr\2.0.0\libraries\SPI Using library Wire at version 1.0 in folder: ...\ArduinoData\packages\lgt8fx\hardware\avr\2.0.0\libraries\Wire exit status 1 narrowing conversion of '1000000' from 'long int' to 'int8_t {aka signed char}' inside { } [-Wnarrowing]

I suspect DisplaySH1107_64x128_I2C display( -1, { -1, 0x3C -1, -1, 1000000 } ); should set I2C frequency to 1MHz. Changing in file lcd_sh1107.h "SPlatformI2cConfig{config.busId, static_cast(config.addr ?: 0x3C), config.scl, config.sda, config.frequency ?: 400000})" to "SPlatformI2cConfig{config.busId, static_cast(config.addr ?: 0x3C), config.scl, config.sda, config.frequency ?: 1000000})" does not give any effect. Changing in file arduino_wire.cpp "Wire.setClock( 400000 );" to "Wire.setClock( 1000000 );" is efficient. The effect was observed commenting all lcd_delay functions in demo file, initialising Serial and printing out demo execution time. Changes in demo file:

... void setup() {

Serial.begin(57600);

...

unsigned long StartMillis; unsigned long CurrentMillis;

void loop() { //lcd_delay(1000); switch (menu.selection()) { case 0: StartMillis = millis(); bitmapDemo(); break; ... case 4: drawLinesDemo(); CurrentMillis = millis(); Serial.print("Test duration, ms:"); Serial.println( CurrentMillis - StartMillis ); break;

...

The execution time changed from default 1503 ms to 808 ms. At I2C frequency 2 MHz it decreased to 576 ms.

• library version: 1.1.4
• LCD display type SH1107 64x128 I2C
• OS: Windows 10
• Platform: LGT8F328P
• IDE: Arduino 1.8.16 from MS store

[lexus2k]

Hi @ggatis

the frequency is not a last parameter in SPlatformI2cConfig. Probably you should you something like this: DisplaySH1107_64x128_I2C display( -1, { -1, 0x3C, 1000000, -1, -1, } );

[ggatis]

Hi @lexus2k! I took the syntax from the demo where it says DisplaySH1107_128x64_I2C display(-1); // or (-1,{busId, addr, scl, sda, frequency})... I think it is the correct sequence since the second arg should go as config structure SPlatformI2cConfig that in short is defined as typedef struct { int8_t busId; uint8_t addr; int8_t scl; int8_t sda; uint32_t frequency; } SPlatformI2cConfig;

And "DisplaySH1107_64x128_I2C display( -1, { -1, 0x3C, 1000000, -1, -1 } );" does not work anyway since the prob is in narrowing, not in the order:

lcdgfx_sh1107_demo:47:69: error: narrowing conversion of '1000000' from 'long int' to 'int8_t {aka signed char}' inside { } [-Wnarrowing] DisplaySH1107_64x128_I2C display( -1, { -1, 0x3C, 1000000, -1, -1 } ); ^ lcdgfx_sh1107_demo:47:69: error: narrowing conversion of '-1' from 'int' to 'uint32_t {aka long unsigned int}' inside { } [-Wnarrowing] Using library lcdgfx at version 1.1.4 in folder: ...\Arduino\libraries\lcdgfx Using library SPI at version 1.0 in folder: ...\ArduinoData\packages\lgt8fx\hardware\avr\2.0.0\libraries\SPI Using library Wire at version 1.0 in folder: ...\ArduinoData\packages\lgt8fx\hardware\avr\2.0.0\libraries\Wire exit status 1 narrowing conversion of '1000000' from 'long int' to 'int8_t {aka signed char}' inside { } [-Wnarrowing]

Kind regards ~

[lexus2k]

I do not observe any narrowing error. Could you please specify platform you're using for the compilation?