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==== Table of Contents ====

[[#dos_65_for_crc65|DOS/65 for CRC65]]

[[#introduction|Introduction]]

[[#dos_65_v3_distribution_files|DOS/65 V3 Distribution Files]]

[[#porting_dos_65_v3_to_crc65|Porting DOS/65 V3 to CRC65]]

[[#crc65_software_for_dos_65|CRC65 Software for DOS/65]]

[[#programs_assembled_in_windows_environment_using_ca65_assembler|Programs assembled in Windows environment using CA65 assembler]]

[[#programs_uploaded_to_dos_65_to_be_assembled_using_dos_65_native_assembler|Programs uploaded to DOS/65 to be assembled using DOS/65 native assembler]]

====== DOS/65 for CRC65 ======

===== Introduction =====

DOS/65 is a CP/M 2.2 clone for 6502 processor. It is created by Richard Leary who has released it as freeware under GNU General Public License V3. Beside the sources of DOS/65, a number of supporting programs are also available as 6502 source codes. Programs such as editor, assembler, debug, super directory, BASIC compiler, BASIC interpreter, Xmodem, and others. This is the [[http://forum.6502.org/viewtopic.php?f=6&t=6440&start=105#p96400|link]] to discussion about porting version 3 of DOS/65 to CRC65.

===== DOS/65 V3 Distribution Files =====

DOS/65 V3 source files can be found [[http://retro.hansotten.nl/uploads/dos65cpm/dos652020src.zip|here]]

Documentations for DOS/65 V3 is [[http://retro.hansotten.nl/uploads/dos65cpm/dos652020docs.zip|here]]

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:dos65v3d_additional.zip|Additional source]] for UCOPY, SD, and SUBMIT programs

===== Porting DOS/65 V3 to CRC65 =====

Because CRC65 bootstrap from the CF disk, the goal is creating a dedicated DOS/65 CF disk that boots directly into DOS/65 at power up. Sometimes it is desirable to have access to CRC65 hardware monitor to perform hardware level diagnostic and load hardware-specific utility software. This can be achieved by loading CRC65 monitor along with DOS/65 system files during power-on bootstrap. CRC65 monitor can be invoked by issuing a “go $b400” command at DOS/65 prompt.

By design, CRC65 loads and executes program stored in Master Boot Record of the CF disk. This bootstrap program will load CRC65 monitor and DOS/65 system program from system track of the CF disk into RAM from $b200 to top of RAM ($E7FF). Once load is completed, the bootstrap will jump to cold-boot routine of DOS/65 at $dc00.

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=9f09aa&media=https://www.retrobrewcomputers.org/lib/plugins/ckgedit/fckeditor/userfiles/image/builderpages/plasmo/crc65/dos65_v3_on_crc65.jpg|{{https://www.retrobrewcomputers.org/lib/exe/fetch.php?w=600&h=415&tok=5f3e84&media=https%3A%2F%2Fwww.retrobrewcomputers.org%2Flib%2Fplugins%2Fckgedit%2Ffckeditor%2Fuserfiles%2Fimage%2Fbuilderpages%2Fplasmo%2Fcrc65%2Fdos65_v3_on_crc65.jpg?600x415|www.retrobrewcomputers.org_lib_plugins_ckgedit_fckeditor_userfiles_image_builderpages_plasmo_crc65_dos65_v3_on_crc65.jpg}}]]

The above screen capture shows DOS/65 booting up. The first line consists of 27 dots each representing a 512-byte CF sector copied into RAM starting from $b200; the 2nd line is DOS/65 sign on message; and the third line starts with DOS/65 command prompt, A0> which denotes Drive A, User 0.

There are two methods of installing DOS/65 on a new CF disk, The easiest method is disk copy a [[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:dos65v3_02_image.zip|DOS/65 image]] to a new CF disk using diskcopy application such as Win32DiskImager in Windows environment. The second method is installing DOS/65 system files serially using a TeraTerm Macro script file. This [[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:dos65v3_serial_upload.zip|zipped file]] contains all software needed to install DOS/65 to a new CF disk by copy all file to c:\teraterm\dos65 and execute the TeraTerm Macro, newDOS65CF_v3fast.ttl.

This is a 6+ minute [[https://www.youtube.com/watch?v=DtIrVBMzIUo|YouTube video]] showing installation of DOS/65 via serial port.

===== CRC65 Software for DOS/65 =====

==== Programs assembled in Windows environment using CA65 assembler ====

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:formatcf.zip|FORMATCF]], this utility program writes $E5 to directories of drive A/B/C/D, effectively format the disk for DOS/65

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:dosboot.zip|DOSBOOT]], this utility program copies DOS/65 bootstrap to Master Boot Record and copy DOS/65 system program and CRC65 monitor to 27 sectors on the system track

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:dos65v3_rev02.zip|DOS65V3]], this is DOS/65 V3 for CRC65, SIM version 0.2

=== DOS/65 executables ===

In order to upload programs into DOS/65 CF disk and use DOS/65's native assembler to assemble source codes, three executable programs must be installed in DOS/65 disk. These programs are assembled in Windows environment using CA65 assembler then upload and save in CF disk using built-in DOS/65 command “save file_size file_name”..

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:asm_for_dos65.zip|ASM]], this is DOS/65 native 6502 assembler

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:mkcom_for_dos65.zip|MKCOM]], this converts ASM output to DOS/65 executable

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:x38sa120_xmodem.zip|XMODEM]], this is the xmodem file transfer program

==== Programs uploaded to DOS/65 to be assembled using DOS/65 native assembler ====

The [[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:crc65:dos65:dos65v3_serial_upload.zip|zipped file]] contains assembly sources of DOS/65 programs that can be assembled using DOS/65's native assember, ASM.COM.