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#91
I'd like to request (whenever / if possible) -
A.M.C. Astro Marine Corps
(although it's split into 2 parts, so I guess that's why it hasn't been done yet and makes it awkward - but it's one of my and many others fav Amstrad games)
Simulador Profesional De Tenis
(I came across this recently, and honestly I think it's the best tennis game on the Amstrad. Would time in nicely with Wimbledon on at present!)
Jax The Dog
(Recent homebrew game, my little boy likes playing this game)
Thanks!
A.M.C. Astro Marine Corps
(although it's split into 2 parts, so I guess that's why it hasn't been done yet and makes it awkward - but it's one of my and many others fav Amstrad games)
Simulador Profesional De Tenis
(I came across this recently, and honestly I think it's the best tennis game on the Amstrad. Would time in nicely with Wimbledon on at present!)
Jax The Dog
(Recent homebrew game, my little boy likes playing this game)
Thanks!
#92
H
Technical support - Hardware related / Re: CPC 464 doesn’t boot, show...
Last post by hatman72 - 19:56, 12 July 25Quote from: Bryce on 19:42, 12 July 25Hi Hatman72,Thanks Bryce. I've had both socketed chips (GA and CPU) out. I know the CPU is ok but my other (working) Amstrad has a 40010 GA so I can't easily test that.
that's not a classic RAM failure. I'd suggest you start by cleaning the pins and reseating all socketed chips and see if it helps.
What's your level of electronics knowledge and do you own any test equipment?
Bryce.
I own a multimeter and a cheap oscilloscope (which allowed me to check there's activity on all the RAM chips, but I'd consider my electronics knowledge to be fairly basic.
#93
Hi deadmeat,
I'd suggest you give the power socket and power switch a good clean. The voltage drop is probably happening in one of those.
Bryce.
I'd suggest you give the power socket and power switch a good clean. The voltage drop is probably happening in one of those.
Bryce.
#94
Technical support - Hardware related / Re: CPC 464 doesn’t boot, show...
Last post by Bryce - 19:42, 12 July 25Hi Hatman72,
that's not a classic RAM failure. I'd suggest you start by cleaning the pins and reseating all socketed chips and see if it helps.
What's your level of electronics knowledge and do you own any test equipment?
Bryce.
that's not a classic RAM failure. I'd suggest you start by cleaning the pins and reseating all socketed chips and see if it helps.
What's your level of electronics knowledge and do you own any test equipment?
Bryce.
#95
H
Technical support - Hardware related / CPC 464 doesn’t boot, shows bl...
Last post by hatman72 - 19:33, 12 July 25Hi everyone, I'm hoping that someone can suggest what might be wrong with this early 464 with a 40007 Gate Array.
When I start it always ends up at this screen with alternating blocks of 128 characters in light blue and purple. There is no beep if I press delete. There seems to be lots of activity on the board and no chips seem to be getting excessively warm. The problem is that since only the CPU and GA are socketed I don't want to start desoldering chips at random as I do not have a desoldering gun.
The computer came to me this way and has been stored in a loft. I have no idea whether it was working when it was put there.
When I start it always ends up at this screen with alternating blocks of 128 characters in light blue and purple. There is no beep if I press delete. There seems to be lots of activity on the board and no chips seem to be getting excessively warm. The problem is that since only the CPU and GA are socketed I don't want to start desoldering chips at random as I do not have a desoldering gun.
The computer came to me this way and has been stored in a loft. I have no idea whether it was working when it was put there.
#96
General Discussion - Introductions / Re: New 3" disks? Floating an ...
Last post by ZorrO - 17:27, 12 July 25Let's be serious, a floppy disk weighs almost nothing and doesn't spin hundreds or thousands of times per second. It doesn't need balancing.
#97
Quote from: XeNoMoRPH on 01:08, 11 July 25Memory bug is fixed, on the last DSK versión.I wonder who did this fix
.Thumbs up for Jörn!
@XeNoMoRPH Works like a charm now.
Out of couriosity, which mode do you prefer?
Stefan
#98
the lower voltage on the board is normal.. usually not quite that low..
but if its working..there is no problem!
there is a diag rom you can replace the onboard rom with.. but.. if ya seeing the basic screen.. its working fine!...so the diag isnt going to tell you much...
https://github.com/issalig/amstrad-diagnostics/blob/main/build/AmstradDiagLower.rom is the one you need to replace the onboard rom (you can use the upper rom version if you have a romboard,m4 etc)
but if its working..there is no problem!
there is a diag rom you can replace the onboard rom with.. but.. if ya seeing the basic screen.. its working fine!...so the diag isnt going to tell you much...
https://github.com/issalig/amstrad-diagnostics/blob/main/build/AmstradDiagLower.rom is the one you need to replace the onboard rom (you can use the upper rom version if you have a romboard,m4 etc)
#99
Hi
I am not so familiar with the Amstrad CPC and I am testing a very badly preserved 464, case was damaged by solvents and was in a very sorry state. I wasn't expecting much but when I powered it up I got the basic screen immediately. I've powered just the motherboard by jumpering 1 and 3 as the tape deck is in a bad shape and need servicing.
As said I got the blue and yellow basic screen however when checking voltage rails and signals, I noticed that the +5V was actually measuring +4.0V, CPC was connected to my bench PSU which was delivering a stable 0.750A on a setting of 5.02v@1.5A so there does not seem to be a short and current does not seem too high. I can't do too many tests until I reassemble everything chips temperatures seems fine, CPU and the video chip are hotter than others and the yamaha is slightly hot, while all others are cold to the touch. Caps are all ceramic, with only one electrolytic that does not seem damaged ... so, is this nominal?
Considering at the moment I have no way to load programs into the computer except typing them with the keyboard, is there any kind of diagnostic rom that will perform a more in depth check?
BR
I am not so familiar with the Amstrad CPC and I am testing a very badly preserved 464, case was damaged by solvents and was in a very sorry state. I wasn't expecting much but when I powered it up I got the basic screen immediately. I've powered just the motherboard by jumpering 1 and 3 as the tape deck is in a bad shape and need servicing.
As said I got the blue and yellow basic screen however when checking voltage rails and signals, I noticed that the +5V was actually measuring +4.0V, CPC was connected to my bench PSU which was delivering a stable 0.750A on a setting of 5.02v@1.5A so there does not seem to be a short and current does not seem too high. I can't do too many tests until I reassemble everything chips temperatures seems fine, CPU and the video chip are hotter than others and the yamaha is slightly hot, while all others are cold to the touch. Caps are all ceramic, with only one electrolytic that does not seem damaged ... so, is this nominal?
Considering at the moment I have no way to load programs into the computer except typing them with the keyboard, is there any kind of diagnostic rom that will perform a more in depth check?
BR
#100
Consequently, we can also replace : LD BC,#0000 :source_skip ;; Skip bytes in source data.
with
LD C,0 :source_skip
since the B' register will always be 0 after the loop, and the C' value will never be greater than 6.
with
LD C,0 :source_skip
since the B' register will always be 0 after the loop, and the C' value will never be greater than 6.
Code Select
ORG &AFC3
y_loop:
LD A,C
EXX
LD B,A ;;B'=x_loop counter
x_loop:
LD A,(DE) : INC DE ;; Load sprite data and update source pointer.
OR A : JR Z,$+3 ;; Is byte opaque?
LD (HL),A ;; Write byte.
INC HL ;; Update target pointer.
DJNZ x_loop
EX DE,HL ;; Swap registers to allow DE=DE+BC.
LD C,0 :source_skip ;; Skip bytes in source data.
ADD HL,BC
EX DE,HL
LD BC,#07FA :target_skip ;; Go to next row and skip bytes on screen.
ADD HL,BC
BIT 6,H ;; Was the screen memory left?
jump_condition: JP Z,$+7
LD BC,#C040 : ADD HL,BC ;; Then correct target pointer.
EXX
DJNZ y_loop