אורח חיים ק״וOrach Chayim 106

Se’if 1א׳

כָּל הַפְּטוּרִים מִקְּרִיאַת שְׁמַע פְּטוּרִים מִתְּפִלָּה, וְכָל שֶׁחַיָּב בִּקְרִיאַת שְׁמַע חַיָּב בִּתְפִלָּה; חוּץ מֵהַמְלַוִּין אֶת הַמֵּת, שֶׁאֵין לַמִּטָּה צֹרֶךְ בָּהֶם, שֶׁאַף עַל פִּי שֶׁהֵם חַיָּבִים בִּקְרִיאַת שְׁמַע, פְּטוּרִים מִתְּפִלָּה.

Those Who Are Exempt From Praying [the Amidah]. Containing 3 S'ifim: All those who are exempt from the Recitation of the Shema are exempt from [the Amidah] prayer and all who are obligated in the Recitation of the Shema are obligated in [the Amidah] prayer, except for those who are accompanying the deceased (i.e. a funeral procession) that are not needed for the [funeral] bier; for even though they are obligated in the Recitation of the Shema, they are exempt from [the Amidah] prayer.

Se’if 2ב׳

נָשִׁים וַעֲבָדִים, אַף עַל פִּי שֶׁפְּטוּרִים מִקְּרִיאַת שְׁמַע חַיָּבִים בִּתְפִלָּה, מִפְּנֵי שֶׁהִיא מִצְוַת עֲשֵׂה שֶׁלֹּא הַזְּמַן גְּרָמָא; וּקְטַנִּים שֶׁהִגִּיעוּ לְחִנּוּךְ, חַיָּבִים לְחַנְּכָם.

Women and slaves, even though they are exempt from the Recitation of the Shema, are obligated in [the Amidah] prayer, because it is a positive mitzvah that is not limited by time. And children that have reached [the age] for education, we are obligated to educate them.

Se’if 3ג׳

מִי שֶׁתּוֹרָתוֹ אֻמָּנוּתוֹ, כְּגוֹן רַשְׁבִּ"י וַחֲבֵרָיו, מִפְּסִיק לִקְרִיאַת שְׁמַע, וְלֹא לִתְפִלָּה; אֲבָל אָנוּ, מַפְסִיקִים בֵּין לִקְרִיאַת שְׁמַע בֵּין לִתְפִלָּה. הַגָּה: וְאִם לוֹמֵד לַאֲחֵרִים, אֵינוֹ פּוֹסֵק, כְּמוֹ שֶׁנִּתְבָּאֵר לְעֵיל סי' פ"ט; וּמִכָּל מָקוֹם פּוֹסֵק וְקוֹרֵא פָּסוּק רִאשׁוֹן שֶׁל קְרִיאַת שְׁמַע; (בֵּית יוֹסֵף סי' ע') וְאִם אֵין הַשָּׁעָה עוֹבֶרֶת, וְיֵשׁ לוֹ שְׁהוּת עֲדַיִן לְהִתְפַּלֵּל וְלִקְרֹא קְרִיאַת שְׁמַע, אֵינוֹ פּוֹסֵק כְּלָל (בֵּית יוֹסֵף בְּשֵׁם הָרַ"ן).

One for whom Torah [study] is one's profession, for example, Rabbi Shimon bar Yochai and his companions, interrupts [Torah study] for the Recitation of the Shema, but not for [the Amidah] prayer. But we do interrupt [studies], whether for the Recitation of the Shema or for [the Amidah] prayer. Gloss: And if one is teaching others, one does not interrupt, as was explained above in [Orach Chayim 89:6]. Nevertheless, one should interrupt and recite the first verse of the Recitation of the Shema (Beit Yosef - Siman 70). And if the time [of the Recitation of the Shema or prayer] is not passing and one still has time left to pray or to recite the Recitation of the Shema, one does not interrupt at all [but finishes studying first]. (Beit Yosef in the name of the Ran)