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#1
General Discussion - Introductions / Re: Introduction to CPC World
Last post by robcfg - Today at 09:46Benvingut, Josep!
Thank you for your kind words, and don't hesitate to ask whatever you may need.
Cheers,
Rob
Thank you for your kind words, and don't hesitate to ask whatever you may need.
Cheers,
Rob
#2
J
General Discussion - Introductions / Introduction to CPC World
Last post by josepprada - Today at 09:35Hello Guys,
I'm Josep, I'm from Barcelona, and a few years ago I began (like a lot of people) to collect retro consoles, but in the process wanted to learn some basic electronic and soldering skills, basically learn-by-doing, so I'm not and electronic expert. I buy them broken and try to repair them.
First I begin with the retro classic consoles (Nintendo, Sega,...) and eventually came to me an Amstrad GX4000, which I didn't hear before. When I was a little kid, my father learned Basic in an academy, and he decided to buy an Amstrad CPC 464 with diskette, my first computer experience, so I was aware of the existence of Amstrad Computers, but not that they build a console. Nowadays, I'm an IT guy, working with servers, so I think that first Amstrad make love computers.
Anyway, the Amstrad GX4000 was not working, and had both cable controllers cut. So I began the process of try to restore this beauty console. Learning mostly from this forum and wiki.
I have done a lot of work on my Amstrad, but now I'm in a point that the forum does not respond my answer and my skills and electronic tools doesn't allow me to continue, and I decided to write a Post to see if you guys can help me!
Thanks in advance, you're doing a great job here, keeping these computers alive in time
Bye!
I'm Josep, I'm from Barcelona, and a few years ago I began (like a lot of people) to collect retro consoles, but in the process wanted to learn some basic electronic and soldering skills, basically learn-by-doing, so I'm not and electronic expert. I buy them broken and try to repair them.
First I begin with the retro classic consoles (Nintendo, Sega,...) and eventually came to me an Amstrad GX4000, which I didn't hear before. When I was a little kid, my father learned Basic in an academy, and he decided to buy an Amstrad CPC 464 with diskette, my first computer experience, so I was aware of the existence of Amstrad Computers, but not that they build a console. Nowadays, I'm an IT guy, working with servers, so I think that first Amstrad make love computers.
Anyway, the Amstrad GX4000 was not working, and had both cable controllers cut. So I began the process of try to restore this beauty console. Learning mostly from this forum and wiki.
I have done a lot of work on my Amstrad, but now I'm in a point that the forum does not respond my answer and my skills and electronic tools doesn't allow me to continue, and I decided to write a Post to see if you guys can help me!
Thanks in advance, you're doing a great job here, keeping these computers alive in time
Bye!
#3
Softcore Hardware Patch Z84C - OUT(C),0
This version is an adapter between Z84C and socket. I wanted to avoid it, but 0.8W scares me.
QS3244 is fine bus gate.
This version is an adapter between Z84C and socket. I wanted to avoid it, but 0.8W scares me.
QS3244 is fine bus gate.
#4
You need 257 identical bytes because the value on the bus is usually FFh, but not guaranteed. That also means your ISR needs to start at an address with matching low/high bytes, eg. C3C3h
On a Plus things are different, because the hardware has support for auto vectoring and thus will put one of four values on the bus with bit 0 guaranteed to be 0. It's broken and doesn't put the correct value on the bus, but does mean you only need an 8 byte vector table and all entries can be set to any address you like.
On a Plus things are different, because the hardware has support for auto vectoring and thus will put one of four values on the bus with bit 0 guaranteed to be 0. It's broken and doesn't put the correct value on the bus, but does mean you only need an 8 byte vector table and all entries can be set to any address you like.
#5
I measured the short-circuit current of the Z84c data line. 20mA.
8x20=160 mA. 750ns pulse 160mA (0.8W).
I will do it, but don't do it at home.
ps. Or maybe I won't.
8x20=160 mA. 750ns pulse 160mA (0.8W).
I will do it, but don't do it at home.
ps. Or maybe I won't.
#6
General Discussion - Introductions / Re: What computer did you have...
Last post by ZorrO - Today at 08:14Only 50 people reading this forum? Come on!
#7
General Discussion - Introductions / Re: What computer did you have...
Last post by ZorrO - Today at 08:14Only 50 people reading this forum? Come on!
#8
Ok guys, it's nice to see Triaxos working so well, but it also party time for a new game. As requested by @overange , here is a new conversion thanks to the work of @Urusergi and @dragon with my humble involvement:
RED HEAT from Ocean
Controls:
J1B1 = Fire
J1UP = Head butt / fire gun
J1DOWN = Duck / Pick up
Pause button = Pause game (any button to resume)
Modifications for the GX4000 version:
- Original title screen but also a new one in mode 0 based on the C64 version,
- Wait for fire on title screen,
- Patched keys,
- Joystick as default controls,
- Plus incompatibility fixed,
- Modified disk access routine,
- Pokes: Unlimited lives and health
Many thanks to @dragon for the modification of the disk access routine to make the game work converted in CPR. You're a real master, dude
RED HEAT from Ocean
Controls:
J1B1 = Fire
J1UP = Head butt / fire gun
J1DOWN = Duck / Pick up
Pause button = Pause game (any button to resume)
Modifications for the GX4000 version:
- Original title screen but also a new one in mode 0 based on the C64 version,
- Wait for fire on title screen,
- Patched keys,
- Joystick as default controls,
- Plus incompatibility fixed,
- Modified disk access routine,
- Pokes: Unlimited lives and health
Many thanks to @dragon for the modification of the disk access routine to make the game work converted in CPR. You're a real master, dude
#9
Like Hannibal said in the A-Team "I love it when a plan comes together" . So here is a new version for :
TRIAXOS from Ariola Soft
So many thanks to @Urusergi for patching this and to @dragon for fixing a nasty bug that made the Amstrad version unplayable since 40 years
Controls:
d-pad = Move the character in the desired direction
J1B1 = Fire / Open inventory (long press)
J1B2 = Pause game (J1B1 to resume game)
Pause button = Quit game
Any direction to quit the inventory, d-pad left/right and J1B1 to select an item (grenade or DHE-IV CHARGES)
Modifications for the GX4000 version:
- Wait for fire on title screens,
- Remapped keys,
- Dynamite game corruption fixed (many thanks to dragon),
- Pokes : Unlimited laser, shield, time.
Triaxos is one of these games on computer in which the publishers seemed to consider that discovering what to do was part of the game itself. Really frustrating, making these games completely cryptic without any reason. I offer you a new instruction manual in the archive to start more easily what is really a hidden gem, mature and more ambitious than many others
You can discover an impressive longplay of the spectrum version here:
https://www.youtube.com/watch?v=hFV6Mrc_Ci0&t=2180s
. So here is a new version for :TRIAXOS from Ariola Soft
So many thanks to @Urusergi for patching this and to @dragon for fixing a nasty bug that made the Amstrad version unplayable since 40 years
Controls:
d-pad = Move the character in the desired direction
J1B1 = Fire / Open inventory (long press)
J1B2 = Pause game (J1B1 to resume game)
Pause button = Quit game
Any direction to quit the inventory, d-pad left/right and J1B1 to select an item (grenade or DHE-IV CHARGES)
Modifications for the GX4000 version:
- Wait for fire on title screens,
- Remapped keys,
- Dynamite game corruption fixed (many thanks to dragon),
- Pokes : Unlimited laser, shield, time.
Triaxos is one of these games on computer in which the publishers seemed to consider that discovering what to do was part of the game itself. Really frustrating, making these games completely cryptic without any reason. I offer you a new instruction manual in the archive to start more easily what is really a hidden gem, mature and more ambitious than many others
You can discover an impressive longplay of the spectrum version here:
https://www.youtube.com/watch?v=hFV6Mrc_Ci0&t=2180s
#10
Manual z80 page 20:
A CPU reset clears the I Register so that it is initialized to 0. The lower eight bits of the pointer must be supplied by the interrupting device. Only seven bits are required from the interrupting device, because the least-significant bit must be a 0.
I misunderstood that bit0 is ignored and used as zero by z80. and that's not the case.
org #41b9
jp #b941 ; int with bit0=0
org %8000
db #B9
org #8001
REPEAT 128
DW #B941
REND
.L8101
DI
LD A,#80 ;8000-80FF
LD I,A
IM 2
RET
CALL &8101
A CPU reset clears the I Register so that it is initialized to 0. The lower eight bits of the pointer must be supplied by the interrupting device. Only seven bits are required from the interrupting device, because the least-significant bit must be a 0.
I misunderstood that bit0 is ignored and used as zero by z80. and that's not the case.
org #41b9
jp #b941 ; int with bit0=0
org %8000
db #B9
org #8001
REPEAT 128
DW #B941
REND
.L8101
DI
LD A,#80 ;8000-80FF
LD I,A
IM 2
RET
CALL &8101