Super turbo PCB layout

Page 2/11
1 | | 3 | 4 | 5 | 6 | 7

By sdsnatcher73

Paragon (1720)

sdsnatcher73's picture

23-04-2021, 07:41

SkalTura wrote:
Quote:

I wonder if instead of putting it on top of the Z80 one could design the print to sit between the socket and the Z80?

That should be no problem, did it with an Atari 2600 also.
But the best solution for doing something like this is to have it shifted a bit, so they are not directly above each other in order to have a bit of room to solder some pins in place.

All in all that would make a much nicer solution I think.

By jltursan

Prophet (2476)

jltursan's picture

23-04-2021, 09:05

@SkalTura: You can find the schematic in this ZIP file ;)

By SkalTura

Champion (315)

SkalTura's picture

23-04-2021, 11:07

jltursan wrote:

@SkalTura: You can find the schematic in this ZIP file ;)

Thx...

Few questions though:
- I see in the schematic some connections without a name. Where D1 to D6 are located, only one connection is named IORQ, where do the other connections go ?
- On IC2, pin 6 and 11 are connected but not named, where does it go ?

And to be sure, this should normally go onto of the Z80 CPU correct ?
So I could also draw a PCB that sits between the Z80 (PCB will fit into the Z80 socket on the board, and the Z80 will fit onto the PCB), correct ?

Give me an couple of days, and I will make a PCB design for you guys, both as JPG/PDF in case you want to make/etch the PCB at home, and as a Gerber file so you can send it out to a PCB manufacturer.

Edit: will it be okay to use mostly SMD components ?

By lintweaker

Champion (391)

lintweaker's picture

23-04-2021, 12:15

SkalTura wrote:

- I see in the schematic some connections without a name. Where D1 to D6 are located, only one connection is named IORQ, where do the other connections go ?

Those diodes can be used to connect signals to for switching the speed back to standard (active low signals). The schematic shows /IORQ as an example. When any IO port operations are done, the speed switches back to the low setting. You can use the remaining inputs to connect for example /SLTSL to switch to low speed when a cartridge slot is selected.

By SkalTura

Champion (315)

SkalTura's picture

23-04-2021, 12:32

lintweaker wrote:

Those diodes can be used to connect signals to for switching the speed back to standard (active low signals). The schematic shows /IORQ as an example. When any IO port operations are done, the speed switches back to the low setting. You can use the remaining inputs to connect for example /SLTSL to switch to low speed when a cartridge slot is selected.

Okay, but I need to know where you want to connect these signals in order to make the PCB layout so I can draw the traces to the Z80 socket.
So please give me all connections you want to have.
Or do you want me to leave them all open, so you can later attach wires ?

By jltursan

Prophet (2476)

jltursan's picture

23-04-2021, 13:05

You can also check the layout in the ZIP file. Also another project based on this (or at least I think so) could serve to get an idea:

MSX - KIT AMPLIACION TURBO 7MHz

The above pcb is based in this document: TURBO 7 MHZ VOOR MSX-2

By Alexey

Guardian (3067)

Alexey's picture

24-04-2021, 11:00

RepairBas has a redesigned board that is mounted on top of the CPU.

By SkalTura

Champion (315)

SkalTura's picture

24-04-2021, 13:14

So, the PCB is a bit more complex to make then expected, but here it is:
TurboMSX Gerber files
These files can be used to have a professional PCB made (not that expensive these days).

It's made after the schematic provided in the ZIP file from "jltursan"
Used all SMD components, except for the Z80 (obviously), and the crystal oscillators.
The inputs (connected to the diodes) are connected to solder holes, as well as the "switch" and LED.
Because I would guess that the switch and LED would be connected with wires anyway to mount it on the outside of the MSX...
The IORQ signal is already connected, as it was in the schematic.

First solder all the SMD components.
Then solder the pins to place the PCB into the MSX socket.
And last place a socket for the Z80. This should fit over the SMD components. If not, just remove some of the plastic from the socket...

Note: Decoupling capacitors were not in the schematic.
C6: 10uF/16v (Tantalum chip capacitor)
C7, C8 and C9: 100nF (SMD 0805 format)
All resistors are also SMD 0805 format.
T1 is the SMD equivalent of the BS170, namely the MMBF170

By SkalTura

Champion (315)

SkalTura's picture

24-04-2021, 13:27

This is a small as I could make it...

By SkalTura

Champion (315)

SkalTura's picture

24-04-2021, 13:29

Please send me some pictures (by email) if you decide to make it.
Smile

Page 2/11
1 | | 3 | 4 | 5 | 6 | 7