Re: [Ql-Users] QL-SD What is it?
It's a good part - $2.26 each at digikey... On Tue, Dec 10, 2013 at 6:35 AM, Miguel Angel Rodríguez Jódar miguel.an...@zxprojects.com wrote: It looks like you used a vintage PLD, which was a good idea. Not so vintage, actually. It's a XC9572XL CPLD from Xilinx, still in production, afaik. It's only that for this prototype, I've used the PLCC44 version, with PLCC44 socket. Production boards may have the VQ64, or TQ100 version (cheaper). ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm -- Dave Park Sandy Electronics, LLC d...@sinclairql.com ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] QL-SD What is it?
It looks like you used a vintage PLD, which was a good idea. Not so vintage, actually. It's a XC9572XL CPLD from Xilinx, still in production, afaik. It's only that for this prototype, I've used the PLCC44 version, with PLCC44 socket. Production boards may have the VQ64, or TQ100 version (cheaper). ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] QL-SD What is it?
On Thursday, 5 December 2013, Colin Mckay Wrote: Please describe the hardware software which forms it, sufficiently for us to know what you are talking about. On Wednesday, 04 December 2013, Peter pg...@q40.de Wrote: the restriction that a QL memory expansion is madatory for QL-SD has been removed. If a QL-SD filesystem of 3 MB size (and Groupsize 8) is attached, there still remains 62.5 KB free memory on an unexpanded QL. Not very much, but enough to load TK2 and still be able do useful things. This way, even an unexpanded QL has more mass storage than the ED floppy interface of a (Super) Gold Card offers, and that at harddisk speed without moving mechanical parts. (Larger filesystems, like the 64 MB default, can not be used on an unexpanded QL at all. This won't change.) We are talking state of the art technology. Surely, a size of 3 Gigabytes would seem to be more appropriate. Why has there to be any restrictions? If this is down to software, then can anything be done about it? Michael ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] QL-SD What is it?
Michael, Nothing to do with software, not much to do with hardware as well, just the basic needs of a computer /Any/ QL (or any other computer) needs memory to store the buffers for the mass storage, in the QL's case there is the added problem that the OS is designed in a way (like a lot of other OSs) that the disk map (the directory, basically) needs to be held in main memory as well. This map needs memory that is deducted from the memory you're working with. You could maybe have 6MB of SD space in an unexpanded QL, but in that case you wouldn't be having any memory left for actually doing something sensible. The 3M Peter mentioned is about the best compromise between memory used for the map and memory used for work. Regards, Tobias Am 10.12.2013 um 17:48 schrieb Michael Bulford: On Thursday, 5 December 2013, Colin Mckay Wrote: Please describe the hardware software which forms it, sufficiently for us to know what you are talking about. On Wednesday, 04 December 2013, Peter pg...@q40.de Wrote: the restriction that a QL memory expansion is madatory for QL-SD has been removed. If a QL-SD filesystem of 3 MB size (and Groupsize 8) is attached, there still remains 62.5 KB free memory on an unexpanded QL. Not very much, but enough to load TK2 and still be able do useful things. This way, even an unexpanded QL has more mass storage than the ED floppy interface of a (Super) Gold Card offers, and that at harddisk speed without moving mechanical parts. (Larger filesystems, like the 64 MB default, can not be used on an unexpanded QL at all. This won't change.) We are talking state of the art technology. Surely, a size of 3 Gigabytes would seem to be more appropriate. Why has there to be any restrictions? If this is down to software, then can anything be done about it? Michael ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] QL-SD What is it?
I have no idea about the zxprojects device on youtube. It's a device that is plugged into the expansion ROM connector. It offers a SD inteface and a 16K ROM with firmware. It is able to perform fast reads by using MOVE.L instruction that can read 4 bytes from the SD card in one instruction. I designed the hardware and ran some tests, which is what you have seen on Youtube (Family Guy opening and so on) For the firmware, Rich Mellor contacted me and told me that Adrian Ives was going to write / adapt a suitable firmware. I sent the prototype I built to Adrian, plus some documentation and the core routines for low level access, so I assume he's working with the interface right now. -- Miguel Angel @zxprojects | www.zxprojects.com ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm