DECmate II-III-Specific Files. CPODT CPODT [aka CPXDT or CPUODT] is a debugging tool for the DECmate II/III/III+ that uses specific control-panel memory functions as implemented on these machines specifically. All CPODT-related files in this directory were recovered from OS/8 format MDC8 [FLP] diskettes created on 19-Nov-1989. Last edit: 25-Feb-2015 cjl Note: File naming conventions are compatible with the intentions of the P?S/8 SHELL overlay directory. In some cases, conversion requires truncation of the names to conform with [possibly MS-DOS and] OS/8 limitations before usage. Time/date stamps on certain files indicate the intentions of release dates of files where applicable. For undocumented files, time/date information represents the latest values that might apply to the file based on where the file was recovered, as specific media are known to have been created on the date and time used. Actual time/date information may be somewhat earlier and will be revised if more accurate information becomes available. OS/8-derived file date information is subject to an anomaly of multiples of eight years due to poor internal design. Information as to refining the date accuracy was obtained from reliable sources unless otherwise indicated. Where applicable, date and time information obtained from authoritative comments within the file will be used. Certain files are known to be older than 01-Jan-1980. Due to the limitations of MS-DOS/Windows, the time/date stamp on these files has been set to 2 seconds after the start of the above date, the lowest supported in these environments; this is done to prevent quirks of Windows directory routines that will report no date if the time is 2 seconds earlier. When moved to a file system capable of better date stamp information such as the P?S/8 SHELL, more accurate information will be applied. [Note: The P?S/8 SHELL environment supports dates from 1-Jan-1900 through 31-Dec-2411.] Directory Listing: ____________________________________________________________________________________ 25-Feb-2015 06/15/1982 12:00 AM 46,405 CPODT.PAL 06/24/1982 12:00 AM 57,412 CPXDT.AA 08/03/1988 12:00 AM 200,606 CPXDT.LST 07/14/1982 12:00 AM 67,288 CPXDT.PAL ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ Program Information CPODT .PAL Source file for CPODT Version 1.0 released 15-Jun-1982. This is an earlier release of the CPODT program than the one named CPXDT.PA as described elsewhere. Apparently this is a preliminary release of CPODT before the program was complete; revisions of the program were released relatively quickly for a time. CPXDT .AA Source file for CPODT Version 1.3 released 24-Jun-1982. This is an earlier release of the CPODT program than the one named CPXDT.PA as described elsewhere. Apparently this is a preliminary release of CPODT before the program was complete; revisions of the program were released relatively quickly for a time. Note: It is apparently a personal preference of the programming staff that worked on this program to use the .AA extension for older releases of the program. CPXDT .LST OS/8 listing file created from the CPXDT.PA source file. The listing needs to be confirmed as the accurate listing that would result using the current CPXDT.PA file; however, this cannot be directly accomplished: 1) The listing file was created by PAL8 under the OS/278 V1 system which was never released. 2) There are internal differences within files created by OS/278 V1 PAL8 and all other versions of PAL8 for other OS/8 family members. While assembling the source file with a different assembler may produce similar results, programs must be written to reconcile the output format differences to be certain the source code is identical. Note: The indicated file date is somewhat misleading; it is several years after the release of CPODT. This date could merely be that of the transfer of the original file to another OS/8 family system that assigned the then-current date to the file. Unfortunately, this cannot be verified because the assembly was performed wihout setting the system date. [Note: Unlike P?S/8, OS/8 family members must have the system date set on every bootup; P?S/8 retains the current [last explicitly set] date permanently unless commands are given to either update or clear the system date setting. As such, P?S/8 current dates as expressed in listing files are inherently quite trustworthy.] If the contents prove to be essentially identical to that which can be produced by assembling the CPXDT.PA file, it is recommended the program be assembled with a newer assembler such as P?S/8 PAL as an alternate to this file. Note: 31-Jan-2015. The source file CPXDT.PA was assembled with PAL8 Version B0 from OS/278 V2; the file differences were for the most part reconciled by appying editing procedures that produced a listing file resembling the output of the PAL8 Version A1 from OS/278 V1. The only differences between the files reveals there are bugs in the "/C" [CREF] option of the earlier PAL8 that tends to corrupt part of the output processing of generated literals; this was apparently fixed in the next complete system release. Thus, it is recommended that CPXDT.LS be ignored in favor of an output listing created by an assembler not presenting these flaws. CPXDT .PAL Source file for CPODT Version 1.5 released 14-Jul-1982. This is a stand-alone debugging tool for use on the DECmate II/III only. It takes advantage of the control-panel memory capability of the 6120 CPU as implemented on the DECmate II, III and III+ to implement an independent software debugger meant to be loaded from an operating system such as OS/278 V1. Another bootable system such as WPS can be booted with CPODT resident to allow debugging of that system. [Note: There is no documentation given as to the exact mechanism used to transfer control; it is conceivable that a rigged version of WPS was required to establish breakpoint control; WPS is a bootable application that can only indirectly support program execution as a system menu entry. It would appear that CPODT can be used to debug almost any main memory program using breakpoints that initiate panel requests. As such, it is less invasive than OS/8 and P/S/8 ODT which require the cooperative effort in the program being debugged of running under the designated operating system and allowing modification of location 0004 in any memory field a breakpoint is required [and in some cases 00004 even if there is are no breakpoints in field 0]. As such, more of the operating system itself can be be debugged using this method. [End-of-file]