TC11 DECtape controller

TC11 controller

The TC11 is the DECtape device controller for the UNIBUS. It supported, and was normally provided with, TU56 dual DECtape drives. (In theory, it could probably have controlled the earlier TU55 single drive, but this is not confirmed.)

There is only one version of the TC11, the TC11-G (although it is almost never referred to by that full name).

Like many of the earlier large peripheral controllers for the PDP-11, the TC11 was a large custom wire-wrapped backplane which bolted into the front of a 19 inch rack, such as an H960; into it plugged about 40 small M-Series FLIP CHIPs.

Device registers

Register	Abbreviation	Address
Control and Status Register	TCST	777340
Command Register	TCCM	777342
Word Count Register	TCWC	777344
Bus Address Register	TCBA	777346
Data Register	TCDT	777350

777340: Control and Status Register (TCST)

ENDZ	PAR	MTE	ILO	SELE	BLKM	DATAM	NEX	UPS	CLK	MMT	DT0-2			XD17-16
15	14	13	12	11	10	09	08	07	06	05	04	03	02	01	00

777342: Command Register (TCCM)

ERROR	Unused	MAINT	DINHB	REV	Unit			READY	IE	EXBA		Function			DO
15	14	13	12	11	10	09	08	07	06	05	04	03	02	01	00

777344: Word Count Register (TCWC)

WC15 <---> WC00
15	14	13	12	11	10	09	08	07	06	05	04	03	02	01	00

777346: Bus Address Register (TCBA)

BA15 <---> BA00
15	14	13	12	11	10	09	08	07	06	05	04	03	02	01	00

777350: Data Register (TCDT)

Data15 <---> Data00
15	14	13	12	11	10	09	08	07	06	05	04	03	02	01	00

Board chart/count table

TC11 controller cards

The Flip Chip module utilization chart for the TC11 backplane is as follows (* = Connector):

Slot	A	B	C	D
1	UNIBUS in
2	UNIBUS out
3
4	M798	M105	M307	M141
5	M784	M7821	G736	M307
6	M784	M796	M111	M113
7	M795		M113	M203
8	M783	M783	M115	M113
9	M149	M149	M115	M602
10	M302	M307	M627	M302
11	M206	M205	M611	M307
12	M239	M112	M161	M111
13	M113	M113	M127	M112
14	M205	M205	M206	M115
15	M121	M121	M207	M119
16	M205	M205	M121	M111
17	M121	M121	M113	M117
18	M161	G879	M228
19	M611	M502	M115	M205
20	M908*	G888	M117	M113
21	G888	G888	M115	M113
22	W032*		M202	M112
23	G888	G888	M117	M606
24		M050	M904*

• The M908 is the command connector
• The W032 is the analog signal connector
• The M904 is the light cable

Module counts

Module counts (drawn from the module count chart, not yet confirmed in the module utilization drawing):

Single height boards:

• 1 - G736 - Jumper module
• 1 - G879 - Transport detector
• 5 - G888 - Manchester read/write amplifier

• 1 - M050 - Inverter Driver
• 3 - M111 - Inverters
• 3 - M112 - NOR Gates
• 8 - M113 - 2-Input NAND Gates
• 5 - M115 - 3-Input NAND Gates
• 3 - M117 - 4-Input NAND Gates
• 1 - M119 - 8-Input NAND Gates
• 5 - M121 - 4-input AND-NOR Gates
• 1 - M127 - 2-2-2-3 AND-NOR Gates
• 1 - M141 - 2-2-2-2 AND-NOR gates
• 2 - M149 - 2-Input NAND Wired OR
• 2 - M161 - Binary to Octal/Decimal Decoder
• 1 - M202 - J-K Flip Flops
• 1 - M203 - S-R Flip Flops
• 6 - M205 - D Flip Flop
• 2 - M206 - D Flip-Flops
• 1 - M207 - J-K Flip-Flops
• 1 - M239 - 4 Bit Counter/Registers
• 2 - M302 - One Shot Delay
• 4 - M307 - Integrating One Shot
• 1 - M502 - Negative Input Converter
• 1 - M602 - Pulse Amplifier
• 1 - M606 - Pulse Generator
• 2 - M611 - High Speed Power Inverter
• 1 - M627 - 4-Input NAND Power Amplifier

Extended single height boards:

• 1 - M105 - UNIBUS Address Selector
• 1 - M7821 - UNIBUS Interrupt Control, 7 bits
• 2 - M783 - Bus Drivers
• 2 - M784 - Bus Receivers
• 1 - M796 - UNIBUS Master Control
• 1 - M798 - Non-inverting UNIBUS Drivers

Double height boards:

• 1 - M228 - Mark Track Decoder

Extended double height boards:

• 1 - M795 - Word Count and Current Memory Address

External links

• TC11 DECtape system manual (DEC-11-HTCB-D)
• TC11 DECtape system engineering drawings (DEC-11-HTCA-D)
• TC11 controller