It has upgraded video and can display EGA graphics. I've only got a CGA monitor so I was hoping that I could display more than 4 colours by using this driver.... unfortunately this driver doesn't appear to be compatible with the PC1640

StolleMan wrote on 2021-07-24, 07:47:

It has upgraded video and can display EGA graphics. I've only got a CGA monitor so I was hoping that I could display more than 4 colours by using this driver.... unfortunately this driver doesn't appear to be compatible with the PC1640

Ah, thanks, I only played with the PC1512 a bit and never saw much mention of this EGA upgade in the PC1640.

StolleMan wrote on 2021-07-24, 05:49:

I've tried this driver with my PC1640 and unfortunately it doesn't work. Don't suppose anybody knows of a driver out there for the 'updated' Amstrad XT?

The PC1640 has real EGA. You cannot use this driver. Choose EGA.

Jinxter wrote on 2021-07-24, 08:05:

The PC1640 has real EGA. You cannot use this driver. Choose EGA.

I only have a CGA monitor, but I understand why there may not be a 16 colour CGA driver in the wild. 16 colour CGA may not be possible with the graphics on the PC1640? Certainly not a priority when it can support EGA. I was just hoping to achieve nicer graphics without changing my monitor.

StolleMan wrote on 2021-07-24, 08:34:

Jinxter wrote on 2021-07-24, 08:05:

The PC1640 has real EGA. You cannot use this driver. Choose EGA.

I only have a CGA monitor, but I understand why there may not be a 16 colour CGA driver in the wild. 16 colour CGA may not be possible with the graphics on the PC1640? Certainly not a priority when it can support EGA. I was just hoping to achieve nicer graphics without changing my monitor.

EGA graphics in 320x200 in 16 colours can be displayed on a CGA monitor.

Jinxter wrote on 2021-07-24, 08:44:

EGA graphics in 320x200 in 16 colours can be displayed on a CGA monitor.

I can't seem to get EGA to work with my setup (just black screen), I assumed it was the monitor. Guess not? Looks like I have some more investigating to do!

Okay, so I got it to work... but it's weird...

If I cold boot and run "SCIV.EXE" from DOS3.2 I get a black screen.
If I run "SCIV.EXE" from GEM it works as it should.
Then if I quit GEM and go back to DOS it works as it should.

This is also the case for Duke Nukem 1 and Commander Keen. There isn't enough memory to run these guys from GEM but they work fine once I quit back to DOS. I'm happy enough with my work-around but I'm finding it a little odd. Commander Keen even returns an error stating that it can't detect compatible graphics.

System specs for anybody interested:
Standard Amstrad PC1640
PCCD Monitor
Amstrad Mouse and Keyboard
A: 360K 5.25"
B: 720K 3.5"
C: XT-IDE CF card with single 32mb partition
MSDOS 3.2 + GEM installed to HDD from original floppies.

PC1640 has a paradise EGA card so no point to try this... It is a completely different graphics chip

keropi wrote on 2021-07-24, 12:04:

PC1640 has a paradise EGA card so no point to try this... It is a completely different graphics chip

Yep, I'm fully across that now. The EGA driver is now working but only after first running GEM.

Sorry I've kinda derailed this thread a bit. I've made a new post for my specific issue: EGA Graphics Weirdness - Amstrad PC1640

Apologies on posting in an old thread but I've been using this thread since I got my childhood Amstrad PC1512 from my parent's place... this is awesome! haha

Anyway, I finally got Thexder working and am just curious if there was a 640x200 16 color port for it as well...... all of the Sierra PC1512 16 color games mentioned in this thread work perfectly! Thanks for the updated DRV file as well, that is mint.

snappy|nuts wrote on 2022-12-24, 04:21:

Anyway, I finally got Thexder working and am just curious if there was a 640x200 16 color port for it as well......

There is none for the PC1512 nor would it make sense:
Due to the way the PC1512's 640x200 16-color mode is implemented, the game would run at a measly 1/4 of CGA speed.

Benedikt wrote on 2022-12-24, 17:06:

There is none for the PC1512 nor would it make sense:
Due to the way the PC1512's 640x200 16-color mode is implemented, the game would run at a measly 1/4 of CGA speed.

ahhh fair enough... thanks for the information!

Benedikt wrote on 2022-12-24, 17:06:

snappy|nuts wrote on 2022-12-24, 04:21:

Anyway, I finally got Thexder working and am just curious if there was a 640x200 16 color port for it as well......

There is none for the PC1512 nor would it make sense:
Due to the way the PC1512's 640x200 16-color mode is implemented, the game would run at a measly 1/4 of CGA speed.

Um, but on the other hand, the Amstrads are no ordinary XT clones.
IBM PC with CGA: 8-Bit 8088, 4,77 MHz
PC1512/1640: 16-Bit 8086, 8 MHz.

So shouldn't the Amstrads be slightly slower or merely half as slow, at worst ?
I mean, wouldn't the better architecture compensate for the graphics overhead ?

I don't know, I'm just curious, as my father had a Schneider PC1512 with a NEC V30.
Unfortunately, PCem/86Box don't emulate a NEC, so I can't check myself. 😅

Edit: Typos fixed.
I haven't played Thexder on a 4,77 MHz PC yet.
There's no YouTube footage right now, also.
But the specs and cover arts at mobygames.com say "Tandy/IBM or PC compatibles 256K".

Yeah I have and NEC V30 installed in my PC1512 ..... Thexder runs fine in CGA.... was just curious if it fell into the same pot as the other Sierra games that can use the PC1512.DRV option.

I don't find much speed difference between CGA and the Amstrad 16 color modes within the Sierra games mentioned in this thread.

snappy|nuts wrote on 2022-12-25, 00:25:

Yeah I have and NEC V30 installed in my PC1512 ..... Thexder runs fine in CGA.... was just curious if it fell into the same pot as the other Sierra games that can use the PC1512.DRV option.

Whoever installed it did make a wise decision here. 🙂👍
Depending on the type of calculations/arithmetics, the NECs are much quicker.
The average improvement over an Intel is about 10%, at least.
That being said, the original 8086 was a much better chip than the 8088, already.
The NECs also support the newer Real-Mode instructions found in 80186, which make DOS programs from the 90s happy.
(Those which were compiled with AT or 80286 PC in mind.)

snappy|nuts wrote on 2022-12-25, 00:25:

I don't find much speed difference between CGA and the Amstrad 16 color modes within the Sierra games mentioned in this thread.

That's cool, glad to hear! 🙂
Maybe Thexder is a bit special here, though.
Like Zeliard, it was from Japan. It seems that Sierra On-Line merely ported the game for the western audience.
So maybe the engine is different and doesn't know things like dirty-rectangle yet (merely update parts on screen which have changend). 🤷‍♂️

Edit: iI forgot to mention. I'm not saying that Benedikt is wrong anyhow.
I just wonder how the better 1512/1640 compares over a standard 4,77 MHz PC.
If things like RAM access are 16-Bit, too, then the Amstrads don't have the PC's bottlenecks.

But on the other hand, I don't know much about Thexder or shoot 'em ups in general.
Scrolling might be an performance issue, but maybe the NEC is better at such calculations,
if V20/V30 or 80186 instructions are used by the engine or the display driver.

Jo22 wrote on 2022-12-25, 01:08:

I did! As soon as I got this PC1512 back in my possession, I retro-brightened it, upgraded the RAM to 640K, installed V30 and 8 […]
Show full quote

snappy|nuts wrote on 2022-12-25, 00:25:

Yeah I have an NEC V30 installed in my PC1512 ..... Thexder runs fine in CGA.... was just curious if it fell into the same pot as the other Sierra games that can use the PC1512.DRV option.

Whoever installed it did make a wise decision here. 🙂👍

I did! As soon as I got this PC1512 back in my possession, I retro-brightened it, upgraded the RAM to 640K, installed V30 and 8087 processors, GoTek rotary dial unit with updated display, XT-IDE, and RadLib AdLib clone card.

The 20MB Seagate hard drive in it still works as well. Surprised the hell out of me!

FYI: The 8-Bit Guy mentioned the Amstrad 16-color graphics mode in his recent video about "Super CGA" cards.

I see SQ1 SCI remake was in the list of 16 color capable PC1512 games in this thread, but I can't find the EGA version of this anywhere!

digger wrote on 2022-12-25, 15:36:

FYI: The 8-Bit Guy mentioned the Amstrad 16-color graphics mode in his recent video about "Super CGA" cards.

Thanks! 😃

I also recommend watching this old video about the AT&T/Olivetti PCs with "CGA" graphics. 🙂
https://www.youtube.com/watch?v=mUCh46_MzZU

It shows how much better an 8086 PC @8 MHz can perform over an IBM PC.
Performance is 3x better, sometimes.

Anyway, I don't mean to go off-topic any further.
- It's just something that both the 6300/M24 have in common with the Schneider PC-1512. Hence the link.

Jo22 wrote on 2023-01-16, 04:37:

Thanks! 😃 […]
Show full quote

digger wrote on 2022-12-25, 15:36:

FYI: The 8-Bit Guy mentioned the Amstrad 16-color graphics mode in his recent video about "Super CGA" cards.

Thanks! 😃

I also recommend watching this old video about the AT&T/Olivetti PCs with "CGA" graphics. 🙂
https://www.youtube.com/watch?v=mUCh46_MzZU

It shows how much better an 8086 PC @8 MHz can perform over an IBM PC.
Performance is 3x better, sometimes.

Anyway, I don't mean to go off-topic any further.
- It's just something that both the 6300/M24 have in common with the Schneider PC-1512. Hence the link.

I've seen Trixter's video on the 6300/M24 before, but thanks for sharing. I recommend it too.

You'll be hard-pressed to teach my anything new about these machines. After all, my Dad's Olivetti M24 was the machine on which I started my journey as a life-long computer geek, back in the late '80s. 😁

To steer this somewhat back on-topic: it's a shame that Olivetti didn't bother to add support for a 16-color 320x200 mode. The on-board graphics of the M24 had 32KB RAM, which would have been enough to support such a mode, at least at 320x200 resolution. But I guess they focused too much on office productivity, with games clearly being an afterthought at best. That's probably also why it didn't support the undocumented cyan/red/white color palette in graphics mode. Games that used that mode would show up on the M24 as cyan/magenta/white. Also, the color monitor of the M24 did not contain the special circuitry to display color 6 as brown. Instead, it would show as dark yellow, kind of like mustard. Gaming just wasn't the prime focus of this system. Although practically every PC/XT-compatible game with CGA support did run flawlessly otherwise, thanks to the very high level of software-level compatibility. Some of the older ones would run too quickly, but you'd have the same problem on a PC/AT or any other "Turbo XT" clone that ran faster than 4.77MHz.

To continue this off-topic tangent in the proper thread, see here for a link to a Sierra SCI driver for the M24's 640x400 hi-res 2-color mode. (Spoiler alert: I remember not noticing any improved picture quality compared to the standard 640x200 2-color CGA driver. But then again, I believe I only tried it on Quest for Glory I. Maybe it performed better with other Sierra SCI adventure games. Perhaps someone should revisit a comparison, or better yet, re-implement such a driver with a more sophisticated dithering algorithm.)