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v1.19.5 update

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This commit is contained in:
Jeff Parsons 2015-09-12 02:47:01 -07:00
commit 2608f0d5e3
2 changed files with 24 additions and 10 deletions
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30
blog/2015/07/17/README.md
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@ -84,6 +84,8 @@ crash, you can dump the instruction history buffer using the Debugger's "dh" com
NOTE: The diskette images contain a pre-release version of Windows 95, as I don't currently have the RTM version on
diskette.
---
August 13, 2015 Update
---
@ -92,12 +94,12 @@ immediately. To monitor DOS calls until the first 36-byte read of PRECOPY1.CAB,
breakpoint and then starting the machine, using the PCjs Debugger *input* field next to the **Enter** button:
m dos off
bp 1ED4:16B4 "let fn=ah;dos;if fn!=3f||cx!=24"
bp 1ED4:16B4 "set fn=ah;dos;if fn!=3f||cx!=24"
g
Alternatively, you can hard-code those commands into the Debugger component of the machine.xml file; eg:
<debugger id="debugger" messages="fault|tss|int" commands='m dos off;bp 1ED4:16B4 "let fn=ah;dos;if fn!=3f||cx!=24"'/>
<debugger id="debugger" messages="fault|tss|int" commands='m dos off;bp 1ED4:16B4 "set fn=ah;dos;if fn!=3f||cx!=24"'/>
Once the 36-byte read is hit, you'll probably want to stop on the next instruction that examine those bytes,
by using a memory read breakpoint:
@ -107,12 +109,12 @@ by using a memory read breakpoint:
and you also might want to change the first breakpoint to stop on *any* file read, and add a second breakpoint
to dump the initial contents of those reads:
bp 1ED4:16B4 "let fn=ah;dos;if fn!=3f"
bp 1ED4:16B4 "set fn=ah;dos;if fn!=3f"
bp FDC8:422A "if fn==3f;di ds:dx;db ds:dx;h;else"
In the current machine, `1ED4:16B4` is the DOS INT 0x21 entry point and `FDC8:422A` is the corresponding IRET.
The first breakpoint sets an internal variable, `fn`, to the value of the **AH** register on entry, so that the second
breakpoint can check the value on exit.
The first breakpoint sets an internal variable, `fn`, to the value of the **AH** register on entry, so that the
second breakpoint can check the value on exit.
Regarding the other Debugger commands shown above, the `dos` command describes the current DOS operation
(alternatively, you could use the `m int on; m dos on` commands to turn on DOS interrupt messages). The `di`
@ -144,6 +146,8 @@ A quick recap of those command prefixes (which you won't see until AFTER you've
80386 Debug register (DR0-DR7) support was recently added, so even WDEB386 read/write breakpoints should work now.
---
August 21, 2015 Update
---
@ -167,9 +171,19 @@ command:
chipset.outPort(0x0043,PIT1_CTRL,0xD2) @1847:DD02
PIT1_CTRL: Read-Back command not supported (yet)
To be continued....
---
[Embedded DeskPro 386](/devices/pc/machine/compaq/deskpro386/vga/4096kb/machine.xml "PCjs:deskpro386::uncompiled:debugger")
September 12, 2015 Update
---
Lots of bugs have been squashed in the past few weeks -- not enough to finish setting up Windows 95, but it's getting
closer. More details on recent releases can be found [here](https://github.com/jeffpar/pcjs/releases).
The machine below has been reconfigured with a hard disk image containing all the Windows 95 SETUP files. The machine
is at the point where Windows 95 SETUP has just rebooted. Click the "Run" button to start the machine. A breakpoint has
already been set in the Debugger that will stop at an address where things appear to go downhill.
[Embedded DeskPro 386](/devices/pc/machine/compaq/deskpro386/vga/4096kb/machine.xml "PCjs:deskpro386:::debugger")
*[@jeffpar](http://twitter.com/jeffpar)*
*July 17, 2015* (updated August 13 and August 21, 2015)
*July 17, 2015 (updated September 12, 2015)*