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

Exit:
A Will contain the error code if an error was encountered.
Z Set if the operation was successful.
7.6.95 @WRSSC SVC-54
This SVC will pass a function code 14 to a disk driver. It is used to write a system
sector (used in the directory cylinder). Where the disk controller supports the IBM Data
Address Mark convention, the controller command should denote the "deleted data mark", or
X'F8' in lieu of the standard data mark (X'FB'). This distinct mark is used in the @RDSEC
command to detect the presence of a system (directory) sector. Other than this Data
Address Mark variation, @WRSSC is the same as @WRSEC; however, the DOS will use @WRSSC
for all writes to the directory cylinder. 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 Contains the number of the cylinder to write.
E Contains the number of the sector to write.
HL A pointer to the buffer containing the sector of data.
Exit:
A Will contain the error code if an error was encountered.
Z Set if the operation was successful.
7.6.96 @WRTRK SVC-55
This SVC will pass a function code 15 to a disk driver. It is used to format a physical
track on a disk drive. Where the data pattern is under software control (as is the case
for floppy disk drives), the data format must conform to that identified in your
controller's reference manual. Hard drives that are formatted by track may use this SVC
to control the track to track formatting. If the target drive is a floppy disk, then it
is necessary to precede the @WRTRK SVC with a drive select via SVC @SLCT. 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.
HL Contains a pointer to the buffer containing the format data
D Contains the number of the cylinder to write.
Exit:
A Will contain the error code if an error was encountered.
Z Set if the operation was successful.
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