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

7.6.36 @GTDCT SVC-81
This SVC will obtain a pointer to the Drive Control Table (DCT) associated with the
requested logical drive. See the section on DRIVE CONTROL TABLE in chapter 4 for detailed
information on the DCT.
Registers Affected: AF, IY.
Entry:
C logical drive number (0-7).
Exit:
IY the Drive Code Table address.
7.6.37 @GTMOD SVC-83
This SVC will locate the entry address of a module resident in memory provided all
resident modules use the established header protocol.
Registers Affected: AF, DE, HL.
Entry:
DE Pointer to the module name terminated with an ETX (or any character in the
range (X'00'-X'1F').
Exit:
HL Returned entry address of the module.
DE Pointer to address of first byte past the module name storage within the
module header.
Z Set if the module is found in memory.
7.6.38 @HDFMT SVC-52
This SVC is used to pass a function 12 (X'0C') to a disk driver. It is commonly used to
pass a "format drive" command to a hard disk controller. See chapter 4 for more
information.
Registers Affected: AF [Note: DOS saves BC, IY; drivers should save registers any
other registers they use].
Entry:
C The logical drive number (0-7).
Exit:
A The return code if an error.
Z Set if no error.
7.6.39 @HEX16 SVC-99
This SVC will convert a 16-bit binary number to hex ASCII.
Registers Affected: AF, HL.
Entry:
DE Contains the value to be converted.
HL A pointer to your 4 character buffer.
Exit:
HL Points to end of buffer + 1.
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