Floating device vectors - Revision history

Jnc: probable explanation for base units

2023-02-08T13:43:30Z

probable explanation for base units

Jnc: Link board

2023-02-08T03:03:53Z

Link board

Jnc: add a bunch of devices from a later version

2022-08-30T01:40:47Z

add a bunch of devices from a later version

Jnc: /* Further reading */ +PDP-11 Architecture Handbook

2022-08-30T01:19:07Z

‎Further reading: +PDP-11 Architecture Handbook

Jnc: /* External links */ dates on cover

2022-08-29T19:57:40Z

‎External links: dates on cover

Jnc: /* External links */ +peripherals handbook (1981)

2022-08-29T19:23:04Z

‎External links: +peripherals handbook (1981)

Jnc: Avoid redir

2021-08-01T23:50:15Z

Avoid redir

Jnc: To go with floating addrs

2021-07-28T15:35:17Z

To go with floating addrs

New page

'''Floating device vectors''' are a block of [[interrupt vector]]s in low [[main memory]] on the [[UNIBUS]] (and later the [[QBUS]]). Originally, each specific [[peripheral]] was assigned a fixed [[address]] for its vector(s); once the number of different device types became large, circa 1975, this was no longer feasible (or scalable), and the 'floating' approach was adopted instead.

In this, a block of vectors (from 0300 to 0776) is allocated for 'floating' devices. Within that block, devices are assigned in a fixed order, with all the devices of any type in a contiguous group. If a device type which has only one vector (4 bytes) has an odd number of devices, and is followed by a device type with pairs (or more) of vectors, which generally are aligned on a 010 boundary, there will have to be an unused vector between them.

The floating devices, in assignment order, are:

{| class="wikitable"
! Rank !! Device !! Size !! Comment
|-
| 1 || [[DC11 asynchronous serial line interface|DC11]] || 010
|-
| 1 || [[TU58]] || 010 || No config for systems with DC11 + TU58
|-
| 2 || [[KL11 asynchronous serial line interface|KL11]] || 010 || Extra units
|-
| 2 || [[DL11 asynchronous serial line interface|DL11-A/DL11-B]] || 010 || Extra units
|-
| 3 || [[DP11-A synchronous serial line interface|DP11]] || 010
|-
| 4 || [[DM11 asynchronous serial line interface|DM11-A]] || 010
|-
| 5 || [[DN11]] || 04
|-
| 6 || [[DM11-BB Modem Control Option|DM11-BB]] || 04
|-
| 7 || [[DH11 asynchronous serial line interface|DH11 modem control]] || 04
|-
| 8 || [[DR11-A General Device Interface|DR11-A]] || 010
|-
| 9 || [[DR11-C general device interface|DR11-C]] || 010
|-
| 10A || [[PA611]] || 04 || Reader
|-
| 10B || [[PA611]] || 04 || Punch
|-
| 11 || [[LPD11]] || 010
|-
| 12 || [[DT11]] || 010
|-
| 13 || [[DX11]] || 010
|-
| 14 || [[DL11 asynchronous serial line interface|DL11-C/DL11-D/DL11-E]] || 010
|-
| 15 || [[DJ11 asynchronous serial line interface|DJ11]] || 010
|-
| 16 || [[DH11 asynchronous serial line interface|DH11]] || 010
|-
| 17 || [[GT40]] || 020
|-
| 17 || [[LSV11]] || 020
|-
| 18 || [[LPS11]] || 030
|-
| 19 || [[DQ11]] || 010
|-
| 20 || [[KW11-W]] || 010
|-
| 21 || [[DU11]] || 010
|-
| 22 || [[DUP11 synchronous serial line interface|DUP11]] || 010
|-
| 23 || [[DV11]] || 014 || Also [[modem]] control
|-
| 24 || [[LK11]] || 010
|-
| 25 || [[DWUN]] || 010
|-
| 26A || [[DMC11]] || 010
|-
| 26B || [[DMR11]] || 010
|-
| 27 || [[DZ11 asynchronous serial line interface|DZ11]] || 010
|-
| 28 || [[KMC11]] || 010
|-
| 29 || [[LPP11]] || 010
|-
| 30 || VMV21 || 010
|-
| 31 || VMV31 || 020
|-
| 32 || VTV01 || 020
|-
| 33 || [[DWR70]] || 020
|-
| 34 || [[RL11 disk controller|RL11]] || 04 || Extra units
|-
| 35 || [[RX211 floppy disk controller|RX211]] || 04
|-
| 36 || [[TS11]] || 04 || Extra units
|-
| 37 || [[LPA11]] || 010
|-
| 38 || [[IP11]] || 04
|-
| 39 || [[KW11-C]] || 010
|-
| 40 || [[RX11 floppy disk controller|RX11]] || 04 || Extra units
|-
| 41 || [[DR11-W]] || 04
|-
| 42 || [[DR11-B parallel interface|DR11-B]] || 04 || Extra units
|}

==See also==

* [[Floating device address space]]

[[Category: UNIBUS]]
[[Category: QBUS]]

@@ Line 126: / Line 126: @@
 | 54 || [[TU81 magtape drive|TU81]] || 02 || Extra units
 |}
 ==See also==

@@ Line 122: / Line 122: @@
 | 52 || PCL11-B || 04
 |-
-| 53 || VS100 || 02
+| 53 || [[VS100]] || 02
 |-
 | 54 || [[TU81 magtape drive|TU81]] || 02 || Extra units

← Older revision		Revision as of 01:19, 30 August 2022
Line 106:		Line 106:

	* [[Floating device address space]]		* [[Floating device address space]]
		+
		+	==Further reading==
		+
		+	* ''PDP-11 Architecture Handbook'' (not online); 'Floating Vectors', in Appendix A

	==External links==		==External links==

@@ Line 109: / Line 109: @@
 ==External links==
-* [http://www.bitsavers.org/pdf/dec/handbooks/EB-20443-20_Peripherals_Handbook_1981.pdf peripherals handbook (1981)] - Appendix D, 'Floating Vectors' (pp. 492-493 of the PDF]
+* [http://www.bitsavers.org/pdf/dec/handbooks/EB-20443-20_Peripherals_Handbook_1981.pdf peripherals handbook (1981-82)] - Appendix D, 'Floating Vectors' (pp. 492-493 of the PDF]
 [[Category: UNIBUS]]
 [[Category: QBUS]]

@@ Line 86: / Line 86: @@
 | 34 || [[RL11 disk controller|RL11]] || 04 || Extra units
 |-
-| 35 || [[RX211 floppy disk controller|RX211]] || 04
+| 35 || [[RX211 floppy disk controller|RX211]] || 04 || Missing from PDP-11 Architecture Handbook
 |-
 | 36 || [[TS11]] || 04 || Extra units
@@ Line 101: / Line 101: @@
 |-
 | 42 || [[DR11-B parallel interface|DR11-B]] || 04 || Extra units
 |}

@@ Line 56: / Line 56: @@
 | 20 || [[KW11-W]] || 010
 |-
-| 21 || [[DU11]] || 010
+| 21 || [[DU11 synchronous serial line interface|DU11]] || 010
 |-
 | 22 || [[DUP11 synchronous serial line interface|DUP11]] || 010