Cart for Homebrews...

[TBCTBC]

Wouldn't one 74LS573 be enough?

[Scouter3d]

Wouldn't one 74LS573 be enough?

Hi,

No, I think because the Data and Adressbus are multiplexed...
If i had enough IO Pins on the Atmega i would not Need a latch at all ...

one port (8Bits) is for the SD-Card
One Port for the RS232
One Port for SRAM (multiplexed 8bit Data and 15bit Addressbus)
One Port for SRAM and Latches / Buffers enable and / R/W / OE Stuff...

The first 573 latches the 8 lower bits of the Addressbus
the second 573 latches the upper 7 bits needed for the 15bits of Address a 32k SRAM Needs

How do you think this can be done with only one latch? As i am no expert at all i am gratefull for every Input!

TOM:-)

[TBCTBC]

No, you're probably right, I didn't think of the sd-card. I'm not very good at this either, but I'd like to try this too. I planning on ordering a USB version of the atmega32 because I want to create a development system. Connect the CV to a PC via USB to quickly transfer software to the SRAM and then test on the real hardware. The USB version is surface mounted, but futurlec (http://www.futurlec.com) sells a cheap adapter.

[Scouter3d]

Hi,

Perfect, so i am not alone trying to build something!
Are you planning on something working like this?

Attach Card via USB to PC
Use a transfer-Software to fill the SRAM
Detach from PC (SRAM bufferd with battery)
Attach to CV and start Game

Or do you have other plans?

TOM:-)

[TBCTBC]

No, I want the PC to be connected to the CV constantly via a USB-cable.

PC<---USB--->atmega<---->SRAM<---->CV

[MADrigal]

My PC is not close to my TV with CreatiVision.

I would prefer a cartridge which could be programmed and removed at will.

[TBCTBC]

Yeah, ofcourse it wouldn't need to be connected at all times, only when developing software.
Instead of, burning eprom, test it, ok didn't work, erase eprom for 15 minutes, burn again....
or even just copying to sd-card, take it out, put it in cart, test it...and so on..

[MADrigal]

why copying to sd card?

it would be great if the programmable cart had a usb jack. you simply connect the card to the pc, copy the .bin file onto the SRAM, and then remove it and use on the console.

that would be a perfect programmable cart

[TBCTBC]

Haven't thought on that actually, the SRAM would need a battery though, but that would be pretty nice to have anyway.

[Scouter3d]

why copying to sd card?

it would be great if the programmable cart had a usb jack. you simply connect the card to the pc, copy the .bin file onto the SRAM, and then remove it and use on the console.

that would be a perfect programmable cart

I agree with MADrigal, this would be the perfect Cart! (I think the Colecovision Cart Mobsie scanned works exactly like that, but with a Flash chip that Needs no Battery... and more Ram and an onscreen Menue to select a game... wow! This cart uses an USB microcontroller http://www.silabs.com/products/mcu/usb/ ... x-34x.aspx in combination with PC-Software to do the trick)

TOM:-)