Re: test386.asm CPU tester

Posted on 2017-11-21, 21:30

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by superfury

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UniPCemu clears AF when using SAR without count(maskcnt!=0). SHL/SHR set it when maskcnt!=0. So their behaviour is OK. The carry/overflow flags and sign/zero/parity flags are giving errors(at least on 8-bit shl)? 8-bit GRP2: byte op_grp2_8(byte cnt, byte varshift) { //word d, INLINEREGISTER word s, …

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Re: test386.asm CPU tester

Posted on 2017-11-21, 10:21

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by superfury

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Eventually managed to fix those shift bugs, by doing the same as IBMulator: - SHL r/m8 has a bit of extra logic(clearing the result with shifts of 16 and 24): if ((EMULATED_CPU>=CPU_80386)) { if ((maskcnt==0x10) || (maskcnt==0x18)) { FLAGW_CF(s); FLAGW_OF(FLAG_CF); overflow = FLAG_OF; s = 0; //Make …

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Re: test386.asm CPU tester

Posted on 2017-11-21, 06:15

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by superfury

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Just fixed the auxiliary flag to set(shl/shr) or clear(sar) on maskcnt!=0. Now shr crashes because of an invalid carry flag? 16-bit: byte op_grp2_8(byte cnt, byte varshift) { //word d, INLINEREGISTER word s, shift, tempCF, msb; INLINEREGISTER byte numcnt, maskcnt, overflow; //word backup; //if (cnt> …

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Re: test386.asm CPU tester

Posted on 2017-11-20, 19:29

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by superfury

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You're right. This is my new code(after some more fixes, now it gets to DAS it seems, before crashing(also some shr before the HLT)): 8086+: //BCD opcodes! byte CPU8086_internal_DAA() { word ALVAL, oldCF, oldAL; CPUPROT1 oldAL = (word)REG_AL; //Save original! oldCF = FLAG_CF; //Save old Carry! ALVAL …

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Re: test386.asm CPU tester

Posted on 2017-11-20, 14:51

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by superfury

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Just recompiled the latest test386.asm, with all tests enabled. It now seems to crash on the AAA undefined flags test? I've taken a look at IBMulator and copied some of it's logic that should make my 8086 and 80186+ flags equal(although some little processor differences still apply, like += 0x106 vs …

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Re: test386.asm CPU tester

Posted on 2017-11-20, 11:15

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by superfury

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I've also just implemented the RCR variant for the Bit Test instructions. The only thing with possible problems that might have been left are the undocumented adjust instruction results.

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Re: test386.asm CPU tester

Posted on 2017-11-19, 10:41

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by superfury

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Nice test suite, most stuff seems to pass except for the typical looping rotates, although I doubt that would cause any problems with programs. Nobody is bored enough to make task switching, security and vm86 tests I guess :) I still agree with that those are still missing from the testsuite(since …

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Re: test386.asm CPU tester

Posted on 2017-11-18, 10:49

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by superfury

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So 32-bit RCR doesn't do modulo 33? But I tried that(&0x1F instead of %33) and the testsuite fails it's results when I do(errors completely, not shifting when supposed to). All others are already as you've described.

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Re: IBM VGA emulation

Posted on 2017-11-17, 20:09

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by superfury

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I see one difference at https://github.com/OBattler/86Box/blob/master … video/vid_ega.c : - port 3C8 returns 2. That's all I see at a glance. Edit: After implementing it in UniPCemu, it still doesn't enable VRAM? The misc output register is still cleared? So no output still?

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Re: IBM VGA emulation

Posted on 2017-11-17, 14:29

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by superfury

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Does any one has a VGA vs EGA difference list, listing all differences between EGA and VGA I/O and timings? I currently have implemented the following differences(the base system is a VGA after all): - Disable internal video drivers(EGA only). - ROM is reversed. - MISC output register starts with …

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Re: IBM VGA emulation

Posted on 2017-11-17, 09:27

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by superfury

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Just found a bug turning EGA clocks to use VGA clocks instead(EGA vs VGA clock determination checked CGA Extension ID 4(Unused) instead of 3(EGA)). But the BIOS still fails setting up VRAM?

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Re: IBM VGA emulation

Posted on 2017-11-17, 00:05

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by superfury

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Although that seems to have been fixed(it continues to POST and even boot on EGA now), the misc output register is still 0x00, thus nothing is in VRAM, no fonts nor text/attributes? Can you see what's going wrong by comparing logs on the EGA? The memory is mapped properly at physical address 0xB8000 …

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Re: IBM VGA emulation

Posted on 2017-11-16, 23:12

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by superfury

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Thinking about it: the fixes on the shift might make it(The EGA BIOS) continue: the shr that wasn't affecting the carry flag(properly) back then might have been fixed in more recent builds.

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Re: IBM VGA emulation

Posted on 2017-11-16, 23:09

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by superfury

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Don't forget to set it to IPS mode(and your emulator as well, if it supports it). That should fix any clock cycle differences between our emulators(which might differ due to different implementations).

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Re: IBM VGA emulation

Posted on 2017-11-16, 22:59

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by superfury

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The BIOS as well as software are properly reading the switches and responding to it(CheckIt displays and VGA BIOS initializes to monochrome or color mode accordingly, depending on the monitor setup(Settings menu -> Video -> Monitor setting. Options are Color(0110) and B/W,Brownscale,Grayscale, …

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Re: IBM VGA emulation

Posted on 2017-11-16, 22:30

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by superfury

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This is about the IBM version of the VGA ISA card. So I am trying to complete my VGA emulation and the VGA bios I am using is ibm_vga.bin from minuszerodegrees. There are a few awkward things about the behavior of the bios and you can see how it shares a lot of code with the IBM EGA bios. For …

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Re: test386.asm CPU tester

Posted on 2017-11-16, 20:21

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by superfury

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So if I understand correctly, the mask only applies to 8/16/32-bit shift/rotates, while 32-bit RCR doesn't mask and instead does modulo 33(according to test results)? And the modulo 8/16/32 mentioned in pretty much all 80386+ documentation isn't applied in the actual 80386(only top 3 bits masked off …

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Re: test386.asm CPU tester

Posted on 2017-11-16, 18:12

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by superfury

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I've logged (after finding and fixing a bug which stops logging when the debugger is logging in common log format always log even during skipping and the Settings menu is loaded) a complete log file, which should contain the problem. It's a log from the start/middle of the HDD BIOS(XT-IDE AT BIOS) …

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Re: Compaq Deskpro 386 keeps complaining about CMOS?

Posted on 2017-11-16, 17:32

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by superfury

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Well, the test AT BIOS i've used before(besides protected mode issues) also said errors exist with the CMOS, but that shouldn't be true(I see it writing and reading values from CMOS RAM and RTC time properly after all)? So a CPU error on it's data? UniPCemu's CMOS emulation: https://bitbucket.org/ …

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Re: test386.asm CPU tester

Posted on 2017-11-16, 12:25

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by superfury

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Oddly enough, with the current fixes based on the test386.asm testsuite, the Compaq BIOS once again fails setting up DMA correctly? It's once again setting the DMA mode control register for self test mode(mode 0(verify) instead of mode 1(mode 2=memory read, mode 3=invalid)) instead of memory write …

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