About LCD_VLCD1 of STM32L073

[HMura.6]

In the data sheet and reference manual of STM32L073, LCD_VLCD1 is 42pin and LCD_VLCD2 is 37pin, but in STM32CubeMX, the instructions are reversed.

Also, at 1/3 bias, the reference manual is supposed to use LCD_VLCD1 and LCD_VLCD2, but STM32CubeMX will now use LCD_VLCD2 and LCD_VLCD3.

Which is correct, the data sheet and reference manual or the STM32CubeMX 6.1.0?

[Amel NASRI]

Hi @HMura.6​ ,

Sorry for missing this post for long time to provide an answer.

Here you are reporting 2 issues:

1- In the data sheet and reference manual of STM32L073, LCD_VLCD1 is 42pin and LCD_VLCD2 is 37pin, but in STM32CubeMX, the instructions are reversed.

That is true. In this discussion, @Imen GH​ has already confirmed some discrepancies between documentation and STM32CubeMX setup. With the help of @Khouloud ZEMMELI​ , this should be fixed in coming versions of both documents and tool.

Here a summary of what we find currently:

Please keep in mind that Product datasheet is the reference in such case.

2- at 1/3 bias, the reference manual is supposed to use LCD_VLCD1 and LCD_VLCD2, but STM32CubeMX will now use LCD_VLCD2 and LCD_VLCD3.

Referring to following table from the reference manual, I assume that both reference manual and STM32CubeMX are aligned:

Are we speaking about same things?

-Amel

Edit done to select a Best Answer: Point 2: for 1/3 bias, I confirm that LCD_VLCD1 and LCD_VLCD2 are the ones to use (LCD_VLCD3 should remain grayed in STM32CubeMX).

Please note that a new English version of RM0367 will be available in order to support all required updates.

[HMura.6]

Thank you for your answer.

In conclusion, which is correct, RM or MX?

If the datasheet is correct, is it okay that MX is wrong?

In addition, the table "VLCD rail connections to GPIO pins" of RM in English and RM in Japanese are also different, but this trusts English.

[Amel NASRI]

Hi @HMura.6​ ,

For point 1: Datasheet is correct, STM32CubeMX and reference manual are wrong. Actions are taken to fix them.

For point 2: I'll check again then come back to you.

-Amel

[HMura.6]

Thank you for your answer.

I understand the contents.

[Amel NASRI · Accepted solution]

Hi @HMura.6​ ,

Point 2: for 1/3 bias, I confirm that LCD_VLCD1 and LCD_VLCD2 are the ones to use (LCD_VLCD3 should remain grayed in STM32CubeMX).

Please note that a new English version of RM0367 will be available in order to support all required updates.

-Amel

[HMura.6]

Thank you for your answer.

I understand that for a 1/3 bias, I would use port of PB2 and PB12 or PE11.

Thank you very much.