Martin, sent you a Digital Equipment Corp discord invite. 
You should br able yo get zll you questions answered there.

Sent from my iPhone

> On Jan 20, 2025, at 16:04, Martin Eberhard via cctalk <[email protected]> 
> wrote:
> 
> I looked at those images on Bitsavers. As far I understand, an RX211 
> controller can't boot a disk with an RX11 bootstrap program. The RX211 uses 
> DMA to transfer the data, while the RX11 requires software to transfer the 
> data in a loop, one word at a time.
> 
> Additionally, RT11 (or any other OS) has to be configured for the RX211, 
> differently than for the RX11, for the same reason. (A good driver would look 
> at the status register and detect whether it is an RX11 or RX211, and adjust 
> accordingly. I don't know if DEC did this or not.)
> 
> Every single-density image that I could find either does not have a boot 
> loader (Track 1, sector 1) or it has a boot loader for the RX11 controller.
> 
> I have not yet found a disk image (single-density or double-density)  for an 
> RX211 that is bootable. This would require both the boot sector to be for the 
> RX211, as well as the RT11 image itself, configured for an RX211 drive. (Or 
> configured to detect the drive type and do the right thing...)
> 
> I'm kind of new the the DEC world (aside from learning PDP11 assembly 
> language in collage...) Any pointers, advice, DISK IMAGES, etc. is greatly 
> appreciated :-)
> 
> Thanks,
> Martin E.

Reply via email to