BitWiz
Experienced Member
I've been having some fun with my Serial Disk Raspberry Pi.
I modified the software to use 3 GPIOs for an RGB LED.
Here is a video of my Serial Disk Tardis with LEDs.
Blue = Waiting for Commands (2Hz, 50% duty cycle)
Green = Sending data to the PDP-8
Red = Receiving data from the PDP-8.
You will be able to see it live at the VCF Midwest Fair next month.
And now for the question.
I know that currently serial disk used RK05 images to be compatible with SIMH and several utilities to create those images.
However, the RK05 is only about 3/4 of what OS/8 can handle on a single volume. Each 1/2 RK05 (one OS/8 device) is 3,232 sectors (256 words).
However OS/8 can handle 4096 sectors (256 words). That means that we could add 864 more sectors to our image. That's 221,184 Words (331.776 bytes). Since Serial Disk allows for 8 images this could add 1,768,472 more words (2,654,208 bytes) of online storage.
I am suggesting that we add support for this as an option to Serial Disk.
Modifying the C code is simple enough for me to do. However, I really don't understand how the OS/8 device drivers are structured.
I presume that modifying the utilities to build the images would not be all that difficult to modify once i understand how OS/8 Device Drivers and Drive Formats are structured.
What do you guys think, is this worth the effort?
How difficult would it be to modify the OS/8 drivers and the image building utilities?
Thanks,
Mike
I modified the software to use 3 GPIOs for an RGB LED.
Here is a video of my Serial Disk Tardis with LEDs.
Blue = Waiting for Commands (2Hz, 50% duty cycle)
Green = Sending data to the PDP-8
Red = Receiving data from the PDP-8.
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You will be able to see it live at the VCF Midwest Fair next month.
And now for the question.
I know that currently serial disk used RK05 images to be compatible with SIMH and several utilities to create those images.
However, the RK05 is only about 3/4 of what OS/8 can handle on a single volume. Each 1/2 RK05 (one OS/8 device) is 3,232 sectors (256 words).
However OS/8 can handle 4096 sectors (256 words). That means that we could add 864 more sectors to our image. That's 221,184 Words (331.776 bytes). Since Serial Disk allows for 8 images this could add 1,768,472 more words (2,654,208 bytes) of online storage.
I am suggesting that we add support for this as an option to Serial Disk.
Modifying the C code is simple enough for me to do. However, I really don't understand how the OS/8 device drivers are structured.
I presume that modifying the utilities to build the images would not be all that difficult to modify once i understand how OS/8 Device Drivers and Drive Formats are structured.
What do you guys think, is this worth the effort?
How difficult would it be to modify the OS/8 drivers and the image building utilities?
Thanks,
Mike