Send cctalk mailing list submissions to cctalk at classiccmp.org To subscribe or unsubscribe via the World Wide Web, visit http://www.classiccmp.org/mailman/listinfo/cctalk or, via email, send a message with subject or body 'help' to cctalk-request at classiccmp.org You can reach the person managing the list at cctalk-owner at classiccmp.org When replying, please edit your Subject line so it is more specific than "Re: Contents of cctalk digest..." Today's Topics: 1. Re: What was a Terminal Concentration Device in DEC's products? (Noel Chiappa) 2. Re: What was a Terminal Concentration Device in DEC's products? (Paul Koning) 3. Re: What was a Terminal Concentration Device in DEC's products? (Chris Zach) 4. Re: What was a Terminal Concentration Device in DEC's products? (Glen Slick) 5. Re: What was a Terminal Concentration Device in DEC's products? (Noel Chiappa) ---------------------------------------------------------------------- Message: 1 Date: Sat, 29 Jan 2022 15:58:53 -0500 (EST) From: jnc at mercury.lcs.mit.edu (Noel Chiappa) To: cctalk at classiccmp.org Cc: jnc at mercury.lcs.mit.edu Subject: Re: What was a Terminal Concentration Device in DEC's products? Message-ID: <20220129205853.15EEA18C07B at mercury.lcs.mit.edu> McNamara's DH11? (I don't know of another DECdevice of that name.) Per: http://www.bitsavers.org/pdf/dec/unibus/EK-ODH11-OP-002_DH11_Asynchronous_1… it's DMA on output only; the input side has a FIFO that has to be emptied by the CPU. Noel PS: I am familiar with the term 'terminal concentrator' from the networking world, but as a generic term, not the name of a particular product. (Although Cisco's first boxes may have included a terminal concentrator, so named.) Noel ------------------------------ Message: 2 Date: Sat, 29 Jan 2022 17:12:41 -0500 From: Paul Koning <paulkoning at comcast.net> To: Noel Chiappa <jnc at mercury.lcs.mit.edu>, "cctalk at classiccmp.org" <cctalk at classiccmp.org> Subject: Re: What was a Terminal Concentration Device in DEC's products? Message-ID: <684F1FCF-A6E6-4F3C-AC39-ADA1504FC9E1 at comcast.net> Content-Type: text/plain; charset=us-ascii Oh. That's amazing, all these years I thought it had DMA both ways. Clearly not. I wonder how I got that misunderstanding. paul ------------------------------ Message: 3 Date: Sat, 29 Jan 2022 18:49:06 -0500 From: Chris Zach <cz at alembic.crystel.com> To: Paul Koning <paulkoning at comcast.net>, "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>, Paul Koning via cctalk <cctalk at classiccmp.org>, Noel Chiappa <jnc at mercury.lcs.mit.edu>, "cctalk at classiccmp.org" <cctalk at classiccmp.org> Subject: Re: What was a Terminal Concentration Device in DEC's products? Message-ID: <24F062E4-8B26-4EB3-A573-B47C69A53B67 at alembic.crystel.com> Content-Type: text/plain; charset=utf-8 Maybe that is the dhv11. Or the dv11 I'll look it up tomorrow On January 29, 2022 5:12:41 PM EST, Paul Koning via cctalk <cctalk at classiccmp.org> wrote: -- Sent from my Android device with K-9 Mail. Please excuse my brevity. ------------------------------ Message: 4 Date: Sat, 29 Jan 2022 16:47:27 -0800 From: Glen Slick <glen.slick at gmail.com> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: What was a Terminal Concentration Device in DEC's products? Message-ID: <CAM2UOwL2hi2Crm7ovphGd+UZFPePV+vUzoduan7a2a5Xo+eimw at mail.gmail.com> Content-Type: text/plain; charset="UTF-8" http://www.bitsavers.org/pdf/dec/qbus/EK-DHQ11-UG-002.pdf DHQ11 User Guide, EK-DHQ11-UG.002 The main application of the M3107 DHQ11 is for interactive terminal handling; it can also be used for data concentration and real-time processing. It has two programming modes, DHV11 and DHU11. The register sets in these modes are compatible with those of the DHV11 and DHU11 respectively. The preferred mode of operation is DHU11 mode. The main features of the DHQ11 are: ? For transmission: DMA transfers; or for each line, program transfers to a 1 character transmit buffer in DHV11 mode, or to a 64-character transmit FIFO in DHU11 mode ? For receive: a 256-entry FIFO buffer for received characters, dataset status changes, and diagnostic information The M3118 CXA16 and the M3119 CXA08 have the same programming interface as the M3107 DHQ11 The M3108 DSV11 can do DMA transfers in both directions, although it is a synchronous interface, not asynchronous. http://www.bitsavers.org/pdf/dec/qbus/EK-DSV11-TM-001_Jan87.pdf DSV11 Technical Manual, EK-DSV11-TM-001 Functional Description (Section 1.5). The DSV11 supports a range of synchronous protocols on the serial interface, and transfers data to and from the host by DMA transfer. This section describes the way in which the DSV11 handles data. On Sat, Jan 29, 2022 at 3:49 PM Chris Zach via cctalk <cctalk at classiccmp.org> wrote: ------------------------------ Message: 5 Date: Sun, 30 Jan 2022 09:26:46 -0500 (EST) From: jnc at mercury.lcs.mit.edu (Noel Chiappa) To: cctalk at classiccmp.org Cc: jnc at mercury.lcs.mit.edu Subject: Re: What was a Terminal Concentration Device in DEC's products? Message-ID: <20220130142646.5614818C074 at mercury.lcs.mit.edu> The DH11, DHV11 and DHU11 are all very similar, although not 100.00% program compatible. (The DHQ11 can be set to exactly emulate either the DHV11 or DHU11.) So, all provide DMA output, but not DMA input. Differences with the DH11 include two full word registers for DMA address, hardware ^S/^Q support, built-in diagnostics, etc. The DHV11 and DHU11 differ in hardware echo, output FIFO, a fix for the infamous DH11 input silo level bug, etc. Noel End of cctalk Digest, Vol 88, Issue 30 **************************************