The other question is, how much software emulation you want. If you emulate a lot, you might end up asking yourself, why not emulate the CPU also and use UQLX.
Expansion serial card?
Re: Expansion serial card?
One thing to keep in mind is that the Raspberry PI usually is a Linux machine that takes a significant time to boot. During this time, the QL would have no microdrive, mouse, serial, etc.
The other question is, how much software emulation you want. If you emulate a lot, you might end up asking yourself, why not emulate the CPU also and use UQLX.
The other question is, how much software emulation you want. If you emulate a lot, you might end up asking yourself, why not emulate the CPU also and use UQLX.
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XorA
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Re: Expansion serial card?
Could use it bare metal like PiTube guys do!Peter wrote:One thing to keep in mind is that the Raspberry PI usually is a Linux machine that takes a significant time to boot. During this time, the QL would have no microdrive, mouse, serial, etc.
Or just a proper custom kernel with custom initramfs and it should boot in less time than the RAM test with a TrumpCard takes to complete.
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Derek_Stewart
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Re: Expansion serial card?
Hi,
I have a RS232 to TTL module from China, cost about £0.99, which can connect to the Raspberry PI GPIO bus, which is MAX3232ACPE but with RS-232 connector to give serial connections.
Sourced from Ebay:
http://www.ebay.co.uk/itm/262625113050? ... =ext,bu=bu
price now £1.99 delivered.
There is a link: https://www.raspberrypi.org/forums/view ... 44&t=10024
Which details the connection of a TTL-RS232 module.
I have the module, but not had time to look at it.
I have a RS232 to TTL module from China, cost about £0.99, which can connect to the Raspberry PI GPIO bus, which is MAX3232ACPE but with RS-232 connector to give serial connections.
Sourced from Ebay:
http://www.ebay.co.uk/itm/262625113050? ... =ext,bu=bu
price now £1.99 delivered.
There is a link: https://www.raspberrypi.org/forums/view ... 44&t=10024
Which details the connection of a TTL-RS232 module.
I have the module, but not had time to look at it.
Regards, Derek
Re: Expansion serial card?
Those were the RS232 modules I have - only tried one on the Dragon 32 at the moment but, ordered two intending the other for the PI for the QL project the arrived very quickly and are very neat.
I have done a bit of bare metal arm asm but, getting it to boot and flashing LED's is about my limit and I understand some of the other hardware on the Pi is difficult to manage or no low level drive access but, not impossible. The ZX Next plans to use a Pi as a co-pro as well. You could argue that the QL already has a co-pro as well - hence the hermes upgrade?
I just thought in the ROM socket it could be a very low impact, cheap and easy way to get new or returning QL (including 128K unexpanded) users into the scene as it is not a simple one to pick up and run with. uQLx is just not the same as typing on the keyboard and watching the dots crawl around on the TV....
At some point as you say you end up thinking ah well let's learn to program an FPGA and build a new machine. There is a place for that as well and perhaps a core for the Myst is the way to do that. Working across so many retro machines the efforts are fragmented, so a way to move to a more common platform rather than custom hardware seemed a good idea so perhaps it has got some traction from your posts?
I have done a bit of bare metal arm asm but, getting it to boot and flashing LED's is about my limit and I understand some of the other hardware on the Pi is difficult to manage or no low level drive access but, not impossible. The ZX Next plans to use a Pi as a co-pro as well. You could argue that the QL already has a co-pro as well - hence the hermes upgrade?
I just thought in the ROM socket it could be a very low impact, cheap and easy way to get new or returning QL (including 128K unexpanded) users into the scene as it is not a simple one to pick up and run with. uQLx is just not the same as typing on the keyboard and watching the dots crawl around on the TV....
At some point as you say you end up thinking ah well let's learn to program an FPGA and build a new machine. There is a place for that as well and perhaps a core for the Myst is the way to do that. Working across so many retro machines the efforts are fragmented, so a way to move to a more common platform rather than custom hardware seemed a good idea so perhaps it has got some traction from your posts?
Re: Expansion serial card?
These RS232 modules all use the flawed QL serial ports. The intent of this thread is to find or design a superior quality serial port that is at least 5x faster than the inbuilt ones.
One answer has been offered but I am open to others.
One answer has been offered but I am open to others.
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Derek_Stewart
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- Joined: Mon Dec 20, 2010 11:40 am
- Location: Sunny Runcorn, Cheshire, UK
Re: Expansion serial card?
I was just answering a question...Dave wrote:These RS232 modules all use the flawed QL serial ports. The intent of this thread is to find or design a superior quality serial port that is at least 5x faster than the inbuilt ones.
One answer has been offered but I am open to others.
Solutions for the QL, Superhermes, Hermes, Tery Harman Fast Serial Board, Jan's Serial Board.
So there are answers to the initially question.
Regards, Derek
Re: Expansion serial card?
Sorry yes my point was to make the Pi an offload processor from the QL (which could provide many more functions and be very standard / cheap for people, so I drifted off topic about how to do that; the idea of putting it on the memory map will allow fairly rapid write even with the limit of the Cartridge port being Read only using address lines for write - I was hoping to direct connect to PI GPIO somehow perhaps with a standard buffer chip).
The Max232 should be able to do 115kbs but as you say TCP/IP would need faster, hence my suggestion of ignoring the serial issue and using the PI TCP/IP stack - the PI also has TTL serial so over a very short distance it should be able to be ramped up really high. Once you can get at it, it also has an SPI interface anyway that can use the WizzNet but again a PI0W has Wifi if that was OK - depending on size constraints using a bigger Pi will give an integrated CAT5 connection.
I was looking at perhaps the memory mapping technique http://theqlforum.com/viewtopic.php?t=389 discussed in this post to communicate with the PI - the post with the technique talks about a direct SPI drive he designed connected to teh Cartridge port - so maybe that it is the way to talk to the PI for me and or your Offload WizzNet directly - we both get what we want...
...and the QL scene gets a new BUS standard we can use for modern products. (hinted at in the same article but, not explained).
The Max232 should be able to do 115kbs but as you say TCP/IP would need faster, hence my suggestion of ignoring the serial issue and using the PI TCP/IP stack - the PI also has TTL serial so over a very short distance it should be able to be ramped up really high. Once you can get at it, it also has an SPI interface anyway that can use the WizzNet but again a PI0W has Wifi if that was OK - depending on size constraints using a bigger Pi will give an integrated CAT5 connection.
I was looking at perhaps the memory mapping technique http://theqlforum.com/viewtopic.php?t=389 discussed in this post to communicate with the PI - the post with the technique talks about a direct SPI drive he designed connected to teh Cartridge port - so maybe that it is the way to talk to the PI for me and or your Offload WizzNet directly - we both get what we want...
...and the QL scene gets a new BUS standard we can use for modern products. (hinted at in the same article but, not explained).