I don't want to use the internal Flash memory but need to address an external Flash memory of 2MB. For this I need 21 address lines. AD0-7 and A8-11 are available. Am I correct that it is possible to use Ports A and B to generate A12-A21? Maybe it's a silly question but I don't have any experience with the µPSD so far. Thanks in advance for any comments. Regards, Werner