I’m confused. In this article http://www.dinonline.org/2010/11/11/vayeitzei-the%C2%A0basics%C2%A0of%C2%A0maaser%C2%A0kesafim/ in the section titled “Are The Poor Obligated in Maaser?” it is written “According to this viewpoint, a poor person would not be obligated in tithing his income, for poor people are exempt from the mitzvah of charity (see Shach, Yoreh De’ah 248:1).”
But in this article http://www.dinonline.org/2010/08/12/laws-of-tzedakah-part-i-the-basic-obligation/ the first rule says that poor people are indeed required to give tzedaka. I realize both articles are in agreement regarding the poor person’s lack of obligation in maaser, but the first one is saying that poor people are not obligated in tzedaka while the second one is saying that they are required. Please clarify this for me.
As you note, the articles are in agreement concerning a poor person being exempt from maaser.
Concerning his obligation in tzedakah, the Rambam and the Shulchan Aruch (Yoreh De’ah 248) rule that even a poor person is obligated to give tzedakah from the money he collects, but this only applies to a poor person who has covered his basic needs. If his basic needs are not covered, he does not have an obligation to give tzedakah (Shach 1, based on 251:3).
This is presumably the resolution to the contradiction.