The Programmer's Guide to TRSDOS Version 6 - Tim Mann's Home ...

CURSOR CHARACTER
Registers Affected: AF, B.
Entry:
B 8; Change the cursor character.
C Contains the new cursor character (or code value).
Exit:
A Will be returned with the current cursor value (for 6.0.1+).
Z Set if the operation was successful.
VIDEO LINE TRANSFER
Registers Affected: AF, BC, DE, HL.
Entry:
B 9; Invoke line transfer
C transfer direction; 0 = buffer to video, 1 = video to buffer.
H video row to transfer (0-23).
DE A pointer to the user's 80-character buffer.
Exit:
A Will contain the error code if an error was encountered.
Z Set if the operation was successful.
7.6.89 @VER SVC-73
This SVC will perform a @WRITE operation followed by a test read of the sector (assuming
that the WRITE required physical I/O) to verify that it will be readable. The test read
will not cause data to be transferred to the file buffer.
Registers Affected: AF.
Entry:
DE A pointer to the FCB for the file to verify.
HL A pointer to the user record buffer (UREC) containing the logical record
(where the LRL is 256).
Exit:
A Will contain an error return code if an error was encountered.
Z Set if the operation was successful.
7.6.90 @VRSEC SVC-50
This SVC will pass a function 10 to a disk driver. The function should verify the
readability of a sector without transferring any data from the disk to the buffer. See
chapter 4 for additional information.
Registers Affected: AF [Note: DOS saves BC, IY; drivers should save any other
registers they use].
Entry:
C Contains the logical drive number.
D Contain the cylinder number to verify.
E Contains the sector number to verify.
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