Rishi: Yājñavalkya-tradition (Śukla-Yajurvedic school attribution; specific ṛṣi ascription not explicit in the provided excerpt).
Devata: Viśve Devāḥ (All the Gods), with functional linkage to prastara/paridhi deities as ritual supports.
Chandas: Yajus (prose formula; not metrical in the strict ṛk-sense).
Samhita Patha (Devanagari)स्र॒वभा॑गा स्थे॒षा बृ॒हन्त॑: प्रस्तरे॒ष्ठाः प॑रि॒धेया॑श्च दे॒वाः । इ॒मां वाच॑म॒भि विश्वे॑ गृ॒णन्त॑ आ॒सद्या॒स्मिन् बर्हिषि॑ मादयध्व॒ ᳪ स्वाहा॒ वाट्
Transliterationsravabhā́gā stheṣā́ bṛhántaḥ prastaréṣṭhāḥ paridhéyāś ca devā́ḥ | imā́ṃ vā́cam abhí víśve gṛṇánta āsádyāsmín barhíṣi mādayadhvam svā́hā vāṭ
Translation诸天神啊,你们分受流注之供献(sravabhāga),安住不动,广大而强盛,最宜居于铺草束(prastara)之上;又有当被环置为围柴(paridhi)者——愿你们众神同声赞咏此我之言,既坐于此祭草座(barhis)上,欢悦沉醉。娑嚩诃(svāhā)!瓦特(vāṭ)!
Padapatha (Word Analysis)स्रव-भा॑गाः । स्थे॒षाः । बृ॒हन्तः । प्रस्तर-ए॒ष्ठाः । परि॒धेयाः । च । दे॒वाः । इ॒माम् । वाच॑म् । अ॒भि । विश्वे॑ । गृ॒णन्तः । आ॒सद्य॑ । अ॒स्मिन् । बर्हिषि॑ । मादयध्वम् । स्वाहा॑ । वाट् ।
Word by Wordस्रवभागाःthe share-receiving (deities), having portions of the oblation इषाःrefreshments; nourishment प्रस्तरेष्ठाःmost fond of the sacrificial grass-spread (prastara) परिधेयाःto be placed around; fit for the enclosing (paridhi) अभिtowards; over; in response to आसद्यhaving sat down; having approached and seated बर्हिषिon the sacred grass (barhis) मादयध्वम्rejoice; be exhilarated स्वाहाsvāhā (oblation-call) वाट्vāṭ (Vedic closing exclamation) 
Entities MentionedV
Viśve Devāḥ (All the Gods)P
Prastara-devatā (deities ‘most at home upon the prastara’)P
Paridhi-devatā (deities linked with the enclosing sticks) Viniyoga (Ritual Application)