|
|
Joined: Mar 2020
Posts: 30 Likes: 3
Member
|
OP
Member
Joined: Mar 2020
Posts: 30 Likes: 3 |
Thank you! enjoy your vacation, we are in no hurry!
|
|
|
|
|
Joined: May 2009
Posts: 2,037 Likes: 78
Very Senior Member
|
|
Very Senior Member
Joined: May 2009
Posts: 2,037 Likes: 78 |
Honestly, if any other dev wants to take a look at this system instead, I would welcome it at this point. This system is baffling the living piss out of me.
The Z80 clearly needs to boot at 0x1800, but the system manual makes it entirely unclear as to how that happens.
The VDU/COMM 8086 boots to 3000:0000, clears interrupts, then executes an "enter 8E8Ch,0C0h" instruction, which puts IP at 0000:0000h in memory that appears otherwise empty.
The "slave" 8086 boots to 4800:0000, clears interrupts, then executes the exact same instruction, with exactly the same results.
At this point I have no idea how this damn thing is even supposed to start up, let alone work.
|
|
|
|
|
Joined: Jun 2001
Posts: 473
Senior Member
|
|
Senior Member
Joined: Jun 2001
Posts: 473 |
0000: e9 ff 03 jmp 402h
0402: fa cli
0403: 8c c8 mov ax,cs
0405: 8e c0 mov es,ax
0407: b8 40 00 mov ax,40h
Not sure how you end up at 0x404.. and the byte order does not match, looks like youre interleave is fucked?
|
|
|
|
|
Joined: May 2009
Posts: 2,037 Likes: 78
Very Senior Member
|
|
Very Senior Member
Joined: May 2009
Posts: 2,037 Likes: 78 |
Could be my interleave is fucked, yeah. I'll have a look in a bit.
|
|
|
|
|
Joined: May 2009
Posts: 2,037 Likes: 78
Very Senior Member
|
|
Very Senior Member
Joined: May 2009
Posts: 2,037 Likes: 78 |
Yeah, it's a byte interleave, not a word interleave like I have it. Alright, I'll put it back on my queue, but it'll have to wait for later today, as I currently have the CD-i CDIC flayed apart.
|
|
|
|
|
Joined: Mar 2020
Posts: 30 Likes: 3
Member
|
|
OP
Member
Joined: Mar 2020
Posts: 30 Likes: 3 |
I am repairing mfm hdd, hopefully being able to restore unix from this disk. just wanted to ask if there were any changes to the emulation driver?
|
|
|
|
|
Joined: May 2009
Posts: 2,037 Likes: 78
Very Senior Member
|
|
Very Senior Member
Joined: May 2009
Posts: 2,037 Likes: 78 |
Not yet. Hasn't been submitted yet. It's on my list of things to do, ideally once I've wrapped up the Space Panic audio netlist, which should be this week.
|
|
1 member likes this:
Xolod |
|
|
|
|
Joined: May 2009
Posts: 2,037 Likes: 78
Very Senior Member
|
|
Very Senior Member
Joined: May 2009
Posts: 2,037 Likes: 78 |
I have the VDU board starting to boot. It currently brings up the MC6845, the two Am9513 timers, clears VRAM, initializes NVRAM, and then hangs because it's waiting for an interrupt.
Unless I missed something, the manual doesn't seem to describe which interrupt lines coming out of the Am9513, or any other chips, are connected to the 8 incoming interrupt lines on the NEC D8259 (NEC clone of Intel 8259 Programmable Interrupt Controller).
if you still have the board, Xolod, would it be possible to probe out which pins on which chips are connected to pins 18 through 25 (IR0 through IR7) on the NEC D8259? At this point I can hopefully make some educated guesses by examining code, but it would be easier to just know it.
|
|
|
|
|
Joined: Mar 2020
Posts: 30 Likes: 3
Member
|
|
OP
Member
Joined: Mar 2020
Posts: 30 Likes: 3 |
Great news! The boards are not at home, but I will try to get the operatives where they are now. I hope COVID lockdown will not interfere with this.
|
|
|
|
Forums9
Topics9,088
Posts119,103
Members5,014
| |
Most Online890
Jan 17th, 2020
|
|
These forums are sponsored by Superior Solitaire, an ad-free card game collection for macOS and iOS. Download it today!
|
|
|
|
