Recent posts

#21

C

Games / Re: Bad CPC games you can't he...

Last post by cwpab - Yesterday at 09:50

The page with the Roland game reviews has some interesting scores too. Nich doesn't seem too happy with most Roland games. 

Roland in the Caves / La pulga: 2
Roland in Time: 3
Roland in Space: 3

Finishing Roland in Space, which I suffered as a kid, with emulator save states was pretty fun for me. The game would be so much better with infinite lives.

Strangely enough, I didn't find any magazine reviews for this game in CPC Power... Too soon for French magazines?

In any case, I think a 5 (as "Ahoy!" has) is a better score for those 3 titles. But if we accept Roland in Space is "bad", then it would be one I can't help but "love".

#22

Other retro / Re: Chiller remake

Last post by Gryzor - Yesterday at 07:12

Oh wow. One of the games I sooo loved to hate. I think it must've been one of the first big frustrations of my life. I got it that Christmas (85 or maybe 86?) and couldn't put it down (partly due to the fact that I didn't have so many other games), but it was always driving me crazy with its pixel-perfect difficulty...

#23

Other retro / Chiller remake

Last post by XeNoMoRPH - Yesterday at 06:18

Chiller is an action-platform game released in 1985 for the Amstrad CPC, developed by Mastertronic. Despite its title, it's not a horror game as it might suggest, but rather a platformer with a somewhat macabre aesthetic but a lighter tone.

A remake of the game is currently being developed for PC by the @pixelartingames team. As you can see in the video, the game maintains its characteristic color scheme and is programmed using the Godot Engine.

#24

N

Applications (CPC and CPC-related) / Re: 3D wireframe : Solid of re...

Last post by Nich - 21:27, 31 March 25

Amstrad Computer User published a listing in their August 1991 issue called Lathe, which does something very similar.

https://www.cpc-power.com/index.php?page=detail&num=19091

#25

Amstrad CPC hardware / Re: Real Time Clock Board

Last post by d_kef - 20:17, 31 March 25

I think that partial address decoding will not be a problem.
Regarding the /CS signal I'm not sure. It's been a long time since I was experimenting with it and I'm pretty sure I took a similar approach that didn't work out. Maybe I'm wrong though. 

Please take a look at the DS12887 datasheet. I think there is a reason /CS is tied to ground but I'm not sure. I'll also take a look at it tomorrow and try to remember...

d_kef

#26

Amstrad CPC hardware / Re: Real Time Clock Board

Last post by ikonsgr - 19:59, 31 March 25

Thanks @d_kef ! 
Now, i took a look at RTC chip pinout and the 3 GAL equations for RTC:
RTCRW =   IOREQ & A1X & WR & !RD & A8 & !A9 & !A7 & !A6 & !A5 & A4 & !A3 & A2 & !A1 & !A0;
RTCDS =   IOREQ & A1X & !WR & RD & A8 & !A9 & !A7 & !A6 & !A5 & A4 & !A3 & A2 & !A1 & !A0;
RTCAS =   IOREQ & A1X & WR & !RD & A8 & !A9 & !A7 & !A6 & !A5 & A4 & !A3 & A2 & !A1 & A0;

Now, instead of having CS to Gnd (always enable),and have complex logic for RW, DS,AS of RTC chip, i thought an alternative of activating CS using an OR gate chip that will combine the 6 address bits for &FBD14/&FBD15 ports that need to be '0' + IORQ=0 , and only then, CS will be active (='0')! AFAIK, there is no device or internal function of CPC that sets the specific 6 address bits at '0' at the same time upon I/O request, so i believe no other address bits will be needed to specifically select RTC chip.
The other 2 pins of RW and DS can go directly to WR and RD of Z80 as this is their function in intel mode (MOT->gnd)
And that leave us with AS (Adress strobe), which is exactly the same with RTCRW except for A0 which is inserted directly and not inverted (!A0). I thought of using A0 on AS pin but i don't know if it will work that way.
What do you think?

#27

V

Games / Re: Supercars - remove squeaki...

Last post by viddi - 19:22, 31 March 25

Haha 

#28

Amstrad CPC hardware / Re: Real Time Clock Board

Last post by d_kef - 19:16, 31 March 25

d_kef, Cyboard is indeed a good idea, if there is a way to "extract" the RTC part and add it to ULIfAC board. Unfortunately i couldn't load schematics file (i'm using DIPTRACE as pcb designing tool, which supports eagle projects, but it gives me an error when i tried to load sch file).

You only need to drive 3 pins: DS, AS, R/W. For address decoding I use a 2x4input AND and a GAL and I don't think you can avoid them easily.
But you can certainly fit the 3 ICs on a small PCB and separate completely the RTC from the rest of the circuit.

Here is the schematic
You cannot view this attachment.

and the GAL equations

Code Select Expand

/*  Cyboard for Amstrad CPC - I/O address decoding logic                  */
/*  Copyright (C) 2023 Dimitris Kefalas                                   */

/*  This program is free software: you can redistribute it and/or modify  */
/*  it under the terms of the GNU General Public License as published by  */
/*  the Free Software Foundation, either version 3 of the License, or     */
/*  (at your option) any later version.                                   */

/*  This program is distributed in the hope that it will be useful,       */
/*  but WITHOUT ANY WARRANTY; without even the implied warranty of        */
/*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         */
/*  GNU General Public License for more details.                          */

/*  You should have received a copy of the GNU General Public License     */
/*  along with this program.  If not, see <http://www.gnu.org/licenses/>. */

Name     cyboard;
PartNo   01 ;
Date     7/02/2023 ;
Revision 01 ;
Designer Dimitris Kefalas ;
Company  ;
Assembly none;
Location IC4 ;
Device   g20v8a ;

/* *************** INPUT PINS *********************/
PIN  1 = A0                      ; /*                                 */
PIN  2 = A1                      ; /*                                 */
PIN  3 = A2                      ; /*                                 */
PIN  4 = A3                      ; /*                                 */
PIN  5 = A4                      ; /*                                 */
PIN  6 = A5                      ; /*                                 */
PIN  7 = A6                      ; /*                                 */
PIN  8 = A7                      ; /*                                 */
PIN  9 = A8                      ; /*                                 */
PIN 10 = A9                      ; /*                                 */
PIN 11 = A1X                     ; /*A15 & A14 & A13 & A12 & A11 & A10*/
/* PIN 12 = GND                                                       */
PIN 13 = !IOREQ                  ; /*                                 */
PIN 14 = !RD                     ; /*                                 */
PIN 23 = !WR                     ; /*                                 */

/* *************** OUTPUT PINS *********************/
PIN 15 = CFA3                    ; /* CF card A3 line                 */
PIN 16 = !W5CS                   ; /* W5100S module Chip select       */
PIN 17 = !PINT                   ; /* PIC Interrupt line              */
PIN 18 = RTCAS                   ; /* RTC Address Strobe              */
PIN 19 = !RTCRW                  ; /* RTC Read/Write                  */
PIN 20 = !RTCDS                  ; /* RTC Data Strobe                 */
PIN 21 = !CFLED                  ; /* CF card activity LED            */
PIN 22 = !CFCS                   ; /* CF card Chip Select             */
/* PIN 24 = VCC                                                       */


/* Logic */

RTCRW =   IOREQ & A1X & WR & !RD & A8 & !A9 & !A7 & !A6 & !A5 & A4 & !A3 & A2 & !A1 & !A0;

RTCDS =   IOREQ & A1X & !WR & RD & A8 & !A9 & !A7 & !A6 & !A5 & A4 & !A3 & A2 & !A1 & !A0;

RTCAS =   IOREQ & A1X & WR & !RD & A8 & !A9 & !A7 & !A6 & !A5 & A4 & !A3 & A2 & !A1 & A0;

PINT =    IOREQ & A1X & RD & !WR & A8 & !A9 & !A7 & !A6 & !A5 & A4 & !A3 & !A2 & !A1 & !A0;

CFA3 =    !A3;

CFCS =    IOREQ & A1X & A8 & !A9 & !A7 & !A6 & !A5 & !A4 & !A3 & A2 & A1
        # IOREQ & A1X & A8 & !A9 & !A7 & !A6 & !A5 & !A4 & A3;

CFCSLED = IOREQ & A1X & A8 & !A9 & !A7 & !A6 & !A5 & !A4 & !A3 & A2 & A1
        # IOREQ & A1X & A8 & !A9 & !A7 & !A6 & !A5 & !A4 & A3;

W5CS =    IOREQ & A1X & A8 & !A9 & !A7 & !A6 & A5 & !A4 & !A3 & !A2;

d_kef

#29

Games / Re: Supercars - remove squeaki...

Last post by Bryce - 18:43, 31 March 25

Have you tried that volume knob on the side of the CPC?

Bryce.

#30

Amstrad CPC hardware / Re: Real Time Clock Board

Last post by poulette73 - 18:39, 31 March 25

Is France still stuck in 2023 ? We've moved on to 2025 here.
Bryce.

LOL 

Hello Bryce,
My screen capture is old... I took it from a photo posted on CPC Rulez..