Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

On 12/6/16 10:05 AM, Toby Thain wrote: On 2016-12-06 1:34 AM, Eric Smith wrote: On Mon, Dec 5, 2016 at 6:53 PM, allison wrote: A bunch of us old digits (former dec engineers) got together and were talking about old systems and the thing that stood out is a general dislike

Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

On 2016-12-06 1:34 AM, Eric Smith wrote: On Mon, Dec 5, 2016 at 6:53 PM, allison wrote: A bunch of us old digits (former dec engineers) got together and were talking about old systems and the thing that stood out is a general dislike for having to use the limited set of

Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

On Mon, Dec 5, 2016 at 6:53 PM, allison wrote: > A bunch of us old digits (former dec engineers) got together and were > talking > about old systems and the thing that stood out is a general dislike for > having > to use the limited set of bus interface chips when there were

Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

On 12/05/2016 06:35 PM, Toby Thain wrote: > On 2016-05-02 9:48 AM, Noel Chiappa wrote: >> > From: Pete Lancashire >> >> > Do you or someone have a list of all the Unibus bus chips ? >> >> I have seen the following bus interface chips used on DEC UNIBUS boards: >> >> Drivers: >> >> 8881 -

Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

On Mon, Dec 5, 2016 at 4:35 PM, Toby Thain wrote: > Has anyone looked at the TI Signal Switch family for QBus? (hat tip Ian > Finder) > I use those for interfacing 5V TTL-compatible stuff to 3.3V logic. It doesn't really solve the major Qbus problems. In particular,

Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

On 2016-05-02 9:48 AM, Noel Chiappa wrote: > From: Pete Lancashire > Do you or someone have a list of all the Unibus bus chips ? I have seen the following bus interface chips used on DEC UNIBUS boards: Drivers: 8881 - Sprague, Signetics - Quad NAND Receivers: 380 - Signetics - Quad

Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

On 5/2/2016 7:04 AM, Mattis Lind wrote: The following chips have been used by DEC to interface to the QBUS, and I have seen many of the above chips (e.g. 8641's) used there too, so I think chips seen on one bus could be used on the other: Drivers: 7439 - Various - Quad NAND Transceivers:

Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

I did a bit of searching in the fall for an 8881 (to fix a busted HALT instruction on a PDP8a). I concluded the 7439 is a pin-for-pin replacement - I can't claim all credit for this, it's probably known by a few people here. My notes say the 8881 will handle 30mA loads. The 7401 will handle

Re: UNIBUS/QBUS interface chips Was: Re: MEM11 update

> The following chips have been used by DEC to interface to the QBUS, and > I have seen many of the above chips (e.g. 8641's) used there too, so I > think chips seen on one bus could be used on the other: > > Drivers: > > 7439 - Various - Quad NAND > > Transceivers: > > 2908 - AMD - Quad latching

UNIBUS/QBUS interface chips Was: Re: MEM11 update

> From: Pete Lancashire > Do you or someone have a list of all the Unibus bus chips ? I have seen the following bus interface chips used on DEC UNIBUS boards: Drivers: 8881 - Sprague, Signetics - Quad NAND Receivers: 380 - Signetics - Quad NOR 314 - Signetics - 7-input NOR 8815 -

Re: MEM11 update

Do you or someone have a list of all the Unibus bus chips ? I'd like to put them in my search list -pete On Mon, Feb 8, 2016 at 2:10 PM, Guy Sotomayor wrote: > >> On Feb 8, 2016, at 2:04 PM, Noel Chiappa wrote: >> >> >> >>> From: Ethan Dicks >> >>>

Another MEM11 update

Just to let everyone know, I'm making pretty good progress. I just hit "code complete" on the FPGA. That means I've written all of the Verilog code for the FPGA that is the heart of the MEM11. This includes *all* of the Unibus functionality. It all synthesizes for the FPGA and the remaining

MEM11 update

Just wanted to let folks know where I am with respect to the MEM11 project. I had decided to take a break from writing J1 code and updating the simulator to actually work on the hardware. To make things easy for myself, I decided to use my FPGA eval board and build a daughter board with CPLDs

Re: MEM11 update

On Mon, Feb 8, 2016 at 3:30 PM, Guy Sotomayor wrote: >> On 2/8/16 10:09 AM, Guy Sotomayor wrote: >>> So, things are moving forward. I also wanted to get folk's opinion on >>> the need to actually produce >>> an SPC form factor board. In other words (and sort of in line with

Re: MEM11 update

> On Feb 8, 2016, at 1:03 PM, Ethan Dicks wrote: > > On Mon, Feb 8, 2016 at 3:30 PM, Guy Sotomayor wrote: >>> On 2/8/16 10:09 AM, Guy Sotomayor wrote: So, things are moving forward. I also wanted to get folk's opinion on the need to

Re: MEM11 update

> On Feb 8, 2016, at 1:29 PM, Ethan Dicks wrote: > > On Mon, Feb 8, 2016 at 4:13 PM, Guy Sotomayor wrote: >> Anything optional will be in sockets. I’ll be putting the UNIBUS >> transceivers >> in sockets because I can’t afford the overage that I’d

Re: MEM11 update

> On Feb 8, 2016, at 12:43 PM, Noel Chiappa wrote: > >> From: Guy Sotomayor > > >> I also wanted to get folk's opinion on the need to actually produce an >> S[P]C form factor board. ... is it OK to have the MEM11 be outside of >> the 11/20 chassis and connect via

Re: MEM11 update

On Mon, Feb 8, 2016 at 11:53 AM, Al Kossow wrote: > > > On 2/8/16 10:09 AM, Guy Sotomayor wrote: > >> So, things are moving forward. I also wanted to get folk's opinion on >> the need to actually produce >> an SBC form factor board. In other words (and sort of in line with

Re: MEM11 update

On 2/8/16 11:53 AM, Al Kossow wrote: On 2/8/16 10:09 AM, Guy Sotomayor wrote: So, things are moving forward. I also wanted to get folk's opinion on the need to actually produce an SBC form factor board. In other words (and sort of in line with how peripherals were done on the original

Re: MEM11 update

> From: Guy Sotomayor > I also wanted to get folk's opinion on the need to actually produce an > S[P]C form factor board. ... is it OK to have the MEM11 be outside of > the 11/20 chassis and connect via BC11A (my replica) cables? Well, that's going to up the cost; for some

Re: MEM11 update

On Mon, Feb 8, 2016 at 1:04 PM, Guy Sotomayor wrote: > > > On Feb 8, 2016, at 12:43 PM, Noel Chiappa > wrote: > > > >> From: Guy Sotomayor > > > > > >> I also wanted to get folk's opinion on the need to actually produce an > >> S[P]C form factor

Re: MEM11 update

> On Feb 8, 2016, at 1:08 PM, Ian S. King wrote: > >> >> See above re: gold edge fingers. I was originally thinking that if I do >> have to >> split the board up, that I’d make them completely independent. But that >> has >> the issue of requiring 2x the number of UNIBUS

Re: MEM11 update

On Mon, Feb 8, 2016 at 4:13 PM, Guy Sotomayor wrote: > Anything optional will be in sockets. I’ll be putting the UNIBUS transceivers > in sockets because I can’t afford the overage that I’d need to provide to the > board house for assembly. I'm starting to get sorry I sold

Re: MEM11 update

> On Feb 8, 2016, at 2:04 PM, Noel Chiappa wrote: > > > >> From: Ethan Dicks > >> I'm starting to get sorry I sold off my surplus NS8641s from Software >> Results 20 years ago. To be fair, I did get over $4 each for them, so at the >> time, it was a good deal for me

Re: MEM11 update

> From: Guy Sotomayor > The reality is that an SPC board will be more expensive because of the > gold edge fingers. Oh, right, forgot about that. Yeah, six of one... > I was originally thinking that if I do have to split the board up, that > I'd make them completely

Re: MEM11 Update

On 7/22/15 7:12 AM, Noel Chiappa wrote: So, I noticed that on some QBUS cards DEC used a quad transceiver with tri-state output (on the card side), the AM2908PC. It has separate tri-state drive enable, and bus drive enable, pins. The FPGA we were looking at supports bi-directional pins

Re: MEM11 Update

Made a lot of progress today. I just wrote a hello world program and got it working so the UART output shows up on the simulator. Took a bit more work as there were a couple of subtle bugs lurking in paths I hadn't fully exercised previously (it's the nature of things). It was more

Re: MEM11 Update

On 7/21/15 6:25 AM, Noel Chiappa wrote: It was interesting to re-read your original message; I and a couple of other people are looking into doing a QBUS card to provide access to modern non-volatile storage (SD cards, USB thumb drives), and in discussing the internal design, we'd planned on

Re: MEM11 Update

From: Guy Sotomayor I took some time off from working on the MEM11 ... I had some time over the past few days, so I spent it working on the simulator. Excellent news! Right now all of the J1 instructions seem to simulate properly. I had to go hunt up your original message:

MEM11 Update

As I mentioned previously, I took some time off from working on the MEM11 for the past several months. I had some time over the past few days, so I spent it working on the simulator. Right now all of the J1 instructions seem to simulate properly. Everything related to the basic simulator also