Category: DOS extenders
Flags: available only in protected mode
INT 21 - Phar Lap 386/DOS-Extender v3.0+ - READ/WRITE SYSTEM REGISTERS AX = 2535h EBX = direction (00h read registers, 01h write) DS:EDX -> system register record (see #01375) Return: CF clear Note: this call is only available under MS Windows if PHARLAP.386 VDD is installed