Update lcd_api.py / One linefeed too many, in case the line is filled up to the last character #29
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One linefeed too many, in case the line is filled up to the last character In case I fill the line to the last row, it skips the following line without replacement and the following line remains empty. This is independent of whether I put a \n at the end of the line or not. If I fill the display only with 19 characters instead of the 20 possible characters, the line jump to the following line works. I walked through your code and the following change in lcd_api.py in "putchar" definition will fix this issue:
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| @@ -140,7 +140,8 @@ def putchar(self, char): | |||
| self.cursor_x += 1 | |||
| if self.cursor_x >= self.num_columns or char == '\n': | |||
| self.cursor_x = 0 | |||
| self.cursor_y += 1 | |||
| if char == '\n': | |||
| self.cursor_y += 1 | |||
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It seems to me that if you output to exactly fill the display without a \n then this change will leave the cursor at the beginning of the last line rather than at the beginning of line 0.
I'll have to write some test code to see what happens.
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With your proposed change, the following test:
lcd.putstr('Line 1 - 01234567890')
lcd.putstr('Line 2 - 01234567890')
lcd.putstr('Line 3 - 01234567890')
lcd.putstr('Line 4 - 01234567890')
lcd.putstr('Line 5 - 01234567890')
results in all 5 lines printing on top of each other on the first line. Without this change, Line 5 overwrites Line 1 (which is what I would have expected).
Can you provide an example test and explain what you're seeing with and without the patch?
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I see the problem: If I use this:
lcd.putstr('Line 1 - 01234567890\n')
lcd.putstr('Line 2 - 01234567890\n')
lcd.putstr('Line 3 - 01234567890\n')
lcd.putstr('Line 4 - 01234567890\n')
lcd.putstr('Line 5 - 01234567890\n')
then I get the blank lines like you describe.
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I fixed the issue via 18bc2e0
One linefeed too many, in case the line is filled up to the last character
In case I fill the line to the last row, it skips the following line without replacement and the following line remains empty. This is independent of whether I put a \n at the end of the line or not. If I fill the display only with 19 characters instead of the 20 possible characters, the line jump to the following line works.
I walked through your code and the following change in lcd_api.py in "putchar" definition will fix this issue: