Hayton BNF886 9v - Public domain dedication image

Illustration of the Battle of Yarmouk (636) at the bottom of the page of BNF Nouvelle acquisition française 886 fol. 9v (early 14th century).
The Saracens are shown with a star and crescent banner, the Byzantines (anachronistically in Crusader era armour) with a star banner. Note that the banner designs are not attributed to factions with any consistency by this illustrator: The star and crescent is also shown as carried by the Mongols in foll. 22r, 32v, 34r, 35v). For a later (mid 14th-century) copy with more developed heraldry, see Vienna ÖNB Cod. 2623[1] fol. 15r. ÖNB, Cod. 2623, f.15r
Hayton's (Faulcon's) text reads:

Lors manda l'empereour Eracles grant secors de genz pour defendre la cité d'Antioche. Qant les genz de l'empereour Eracles furent parvenuz jusques à une plainure qui est nomée Possent (var.: Posserit), les Sarazins vindrent à l'encontre; e là fu comencée molt grant bataille que longuement dura; mès, à la fin, les Sarazins en orent la victoire, e tant gent furent ocis en cele bataille que encores y perent les ossements des seignors en celui champ. Dont il avint que les Grex, qui tenoient la cité d'Antioche, furent molt espoentés, e rendirent la terre as Sarazins par convenances. (La Flor des Estories de la Terre d'Orient II.1, ed. Dardel 1906, p. 137.)