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TBC · 13th November 2009, 14:46

hi chaps !

I just popped over to look at the question being framed by nozzer and see if maybe there was a simple reason why it was causing confusion.

I think you might be better off forgetting keyrolls ect for a time, i think the way this is being put across is from the aspect of starting from scratch yet building a conoceptual understanding based on pulling the code apart.

first off one of the thing that make serial comms different from parallel ect is the way data is transmitted. 1 single bit at a time rather than bytes or words.
If things are sent 1 bit at a time as they are in iso comms and rs232 then each bit is received loaded then the next bit is received and loaded until you get a full word - then you can store the word to ram. and get the next.

There are 2 forms of serial comms that can be utilised. Asychronous and synchronous, 1 meaning use of a common clock and one meaning on the fly. The later often utilizes start and stop bits.

I realise this doesn't give you much to go on BUT it does actually help point your googling i think. Without knowing how data is exchanged on a basic level in a serial form you wouldn't even be able to start looking at a keyroll ect becuase you couldn't get the card firmware to understand the host device and visa versa. It's very much the same in glitchers.

here's a for example of how stuff can mess up;

a while ago i was trying to make a flash to run at 18mhz, the comms are serial and so they have to be timed correctly. After a while pulling the original code apart i thought i had it all worked out. I was wrong lol, what i was getting back was supposed to be an ATR but it didn't make any sense. After studying it for ten minutes i realised all the bits were shifted left so the bytes were all wrong. Of course i'd spent that much time on it by then i was able to see the flaw and fix it straight away.

So get googling serial comms protocols and have a look at iso smartcard protocols as well, should give you a good step in the right direction. Especially since there is source code for the funcards knocking about over the net.

13th November 2009, 14:46	#66 (permalink)
TBC Moderator + Join Date: May 2005 Posts: 4,016 Downloads: 0 Uploads: 0 Thanks: 0 Thanked 3 Times in 3 Posts	Re: Want to learn to make fun flash! hi chaps ! I just popped over to look at the question being framed by nozzer and see if maybe there was a simple reason why it was causing confusion. I think you might be better off forgetting keyrolls ect for a time, i think the way this is being put across is from the aspect of starting from scratch yet building a conoceptual understanding based on pulling the code apart. first off one of the thing that make serial comms different from parallel ect is the way data is transmitted. 1 single bit at a time rather than bytes or words. If things are sent 1 bit at a time as they are in iso comms and rs232 then each bit is received loaded then the next bit is received and loaded until you get a full word - then you can store the word to ram. and get the next. There are 2 forms of serial comms that can be utilised. Asychronous and synchronous, 1 meaning use of a common clock and one meaning on the fly. The later often utilizes start and stop bits. I realise this doesn't give you much to go on BUT it does actually help point your googling i think. Without knowing how data is exchanged on a basic level in a serial form you wouldn't even be able to start looking at a keyroll ect becuase you couldn't get the card firmware to understand the host device and visa versa. It's very much the same in glitchers. here's a for example of how stuff can mess up; a while ago i was trying to make a flash to run at 18mhz, the comms are serial and so they have to be timed correctly. After a while pulling the original code apart i thought i had it all worked out. I was wrong lol, what i was getting back was supposed to be an ATR but it didn't make any sense. After studying it for ten minutes i realised all the bits were shifted left so the bytes were all wrong. Of course i'd spent that much time on it by then i was able to see the flaw and fix it straight away. So get googling serial comms protocols and have a look at iso smartcard protocols as well, should give you a good step in the right direction. Especially since there is source code for the funcards knocking about over the net.
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