There is no audio commentary, so please turn on the subtitles. This video demonstrates updating the interpreter's PROMs on my homemade computer PERSEUS-8 by using homemade PROM programmer. The updated ROMs will be applied to PERSEUS-9 after this. PROM programmer parts: CMOS logic IC, 74HC374 x3, DC-DC converter, CCG1R5-12-12D x1. For more detail of this computer, see For more detail of this interpreter, see