System information

FUNCTION 20: READ SEQUENTIAL

Entry Parameters:

Registers DE: FCB Address

Returned Value:

Given that the FCB addressed by DE has been activated through an Open or Make function, the

Read Sequential function reads the next 128-byte record from the file into memory at the current

DMA address. The record is read from position cr of the extent, and the cr field is automatically

incremented to the next record position. If the cr field overflows, the next logical extent is

automatically opened and the cr field is reset to zero in preparation for the next read operation.

The value 00H is returned in the A register if the read operation was successful, while a nonzero

value is returned if no data exist at the next record position (for example, end-of-file occurs).

5.2 Call Conventions CP/M Operating System Manual

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