|LOW ||LOW ||External ROM, 4K at 0000h..0FFFh ||No hardware known to use this
|-
|LOW ||HIGH ||External ROM, 16K at 0000h..3FFFh ||Schneider [[NLQ401]] Printer (uPD7811 with internal ROM disabled)|-
|HIGH ||LOW ||'''Internal''' ROM, 4K at 0000h..0FFFh||Amstrad DMP2000/DMP3000 Printer (uPD7811 with internal ROM enabled)
|-