MicroUSB. Whats a preferred alternative interface?
in [Commodore]
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From: Tristan Mumford on 13 Dec 2006 20:05 On Wed, 13 Dec 2006 16:50:26 -0800, agila61 wrote: > Tristan Mumford wrote: >> I kknow there was a good discussion years ago on using uCs for emulating >> logic on a c64. I believe it was deemed impractical at the time. They run >> faster now so it's not as much of a limitation. The code still needs to be >> well written though. > > And for someone like me, for logic its probably more attractive to > learn how to program a SPLD like the PEEL18CV8. > > Then with one or a few chips I got all the old fashioned random logic I > would every really need. for low chipcount things I'd definitely prefer standard logic. All the pins on PLDs etc give me a headache. Especially PLCC. Mostly because of the sockets. because of doubts I have to confirm each pin equates with the contact in the socket. Confusing things. I have a couple of CYsomething32 CPLDs I've been meaning to try out. I discovered I can't fit much on them, but that's nothing major. I fit a sync generator on to one (from fpga4fun.com), but the rest of the pong game was a little large. -- -----> http://members.dodo.com.au/~izabellion1/tristan/index.html <----- ===== It's not pretty, it's not great, but it is mine. =====
From: agila61 on 14 Dec 2006 02:55 Tristan Mumford wrote: > for low chipcount things I'd definitely prefer standard logic. All the > pins on PLDs etc give me a headache. Especially PLCC. Mostly because of > the sockets. because of doubts I have to confirm each pin equates with the > contact in the socket. Confusing things. The S in SPLD stands for SIMPLE Programmable Logic device. A PEEL18CV8 has 20 pins, and is available in DIP, so face the notch up and the pins are 1 to 10 down the left side and 11 to 20 up the right. Pins 1-9 and 11 are Input, pins 12-19 are I/O, 10 is ground, 20 is Vcc, +5v. (PEEL is Programmable, Electrically Erasable Logic) So using SPLDs is more like working with random logic, except you get to customise the random logic parts.
From: Tristan Mumford on 14 Dec 2006 20:48 On Wed, 13 Dec 2006 23:55:45 -0800, agila61 wrote: > Tristan Mumford wrote: >> for low chipcount things I'd definitely prefer standard logic. All the >> pins on PLDs etc give me a headache. Especially PLCC. Mostly because of >> the sockets. because of doubts I have to confirm each pin equates with the >> contact in the socket. Confusing things. > > The S in SPLD stands for SIMPLE Programmable Logic device. A PEEL18CV8 > has 20 pins, and is available in DIP, so face the notch up and the pins > are 1 to 10 down the left side and 11 to 20 up the right. Pins 1-9 and > 11 are Input, pins 12-19 are I/O, 10 is ground, 20 is Vcc, +5v. > > (PEEL is Programmable, Electrically Erasable Logic) > > So using SPLDs is more like working with random logic, except you get > to customise the random logic parts. Ohh. I see. SO they're just the smaller sibling of the programmable logic family. I have some old altera 20 pin PLA things that I've never used. No idea how to program the things. Last time I checked there were no online specsheets. Shame really. They would be so useful. So these PEEL18CV8 ICs. In real-world terms how much can you fit on them? say something like a few counters and shift registers, or something a bit more complex? -- -----> http://members.dodo.com.au/~izabellion1/tristan/index.html <----- ===== It's not pretty, it's not great, but it is mine. =====
From: agila61 on 15 Dec 2006 01:13 Tristan Mumford wrote: > Ohh. I see. > SO they're just the smaller sibling of the programmable logic family. > I have some old altera 20 pin PLA things that I've never used. No idea how > to program the things. Last time I checked there were no online specsheets. > Shame really. They would be so useful. > So these PEEL18CV8 ICs. In real-world terms how much can you fit on them? > say something like a few counters and shift registers, or something a bit > more complex? Not that much! An 8 bit latch, with all the state on the input lines. A hex shift register, with 2 bits of state available for a state machine .... a 2 bit slice of an adder, with carry in and carry out ... the 8 I/O lines are the bits you have to work with. But of course with 10 input lines, you can have one of them running the state machine and driving several others. Like I said, its more like old school random logic than a CPLD or FPGA.
From: Tristan Mumford on 15 Dec 2006 05:56
On Thu, 14 Dec 2006 22:13:35 -0800, agila61 wrote: > Tristan Mumford wrote: >> Ohh. I see. >> SO they're just the smaller sibling of the programmable logic family. >> I have some old altera 20 pin PLA things that I've never used. No idea how >> to program the things. Last time I checked there were no online specsheets. >> Shame really. They would be so useful. > >> So these PEEL18CV8 ICs. In real-world terms how much can you fit on them? >> say something like a few counters and shift registers, or something a bit >> more complex? > > Not that much! An 8 bit latch, with all the state on the input lines. A > hex shift register, with 2 bits of state available for a state machine > ... a 2 bit slice of an adder, with carry in and carry out ... the 8 > I/O lines are the bits you have to work with. But of course with 10 > input lines, you can have one of them running the state machine and > driving several others. Like I said, its more like old school random > logic than a CPLD or FPGA. Ah right. It's more of an all purpose 'fantasy' chip, that fills the "I wish I had an IC that does X" kind of area. That could be extremely useful. -- -----> http://members.dodo.com.au/~izabellion1/tristan/index.html <----- ===== It's not pretty, it's not great, but it is mine. ===== |