TM11 magtape controller
The TM11, TMA111 and TMB11 magtape controllers are a series of UNIBUS device controllers, used with 1/2" magtape drives. They are all compatible, both in their interface to the drives, and in their programming interface.
The TM11 and TMA11 are almost identical in construction; they are implemented as a series of smaller standard FLIP CHIPs in a custom-wired 19" backplane.
The TMB11 is a re-implementation, using two larger custom boards - one hex (M7912) and one quad (M7911) - along with 4 UNIBUS-specific FLIP CHIPs (M105, M795, M796, M7821); all of which plug into a custom hex-high four-slot system unit (for a BA11, etc box).
The TM11 series controllers connect to a 'Master drive', which includes considerable extra electronics; additional 'Slave' drives may be connected to the Master drive.
Much of the extra functionality is related to the operation of the drive (CRC, etc); however, the TM11 series controllers generate a Positive bus, which a Master drive (depending on the drive type in use) converts to a Negative bus for the Slave drives - Slave drives of that type have a Negative bus only.
The TM11 series controllers were initially used with the TU10 drives, for which the slaves are all Negative bus. Later, they were used with the TS03 drive (for which the Master drive includes an M8920 board). They were also used with the TU10W drive (which is the later TU16 drive, without the TM02 controller); and the TE16 drive, when it is upgraded to TE10W (Positive bus - Master and Slave) or TE10N (Negative bus - Slave).
The connection to the master drive is a standard dual-width BC11-A cable, as used for the UNIBUS. This is the pinout for the TM11 (the other two are basically identical to this):
|AA1||SEL0||Tape unit select||Controller||AA2|
(see table below)
|AJ1||WXG||Write Extended Gap||Controller||AJ2||WD4|
|AR1||AR2||SET||Required to start any tape operation|
|AS1||AS2||WDR||Write Data Ready|
|AU1||AU2||WFMK||Write File Mark|
|BB1||SDWN||Tape Settle Down||BB2||Ground|
|BC1||TUR||Tape Unit Ready||BC2|
|BF1||RD0||Read Data||Drive||BF2||RWS||Rewind Status|
|BK1||RD3||BK2||BOT||Beginning of Tape||Drive|
|BM1||RD5||BM2||VPE||Vertical Parity Error|
|BR1||RDP||Read Parity Bit||Drive||BR2||EOT||End of Tape|
|BS1||FMK||File Mark Read||BS2||CRCE||CRC Error|
|BT1||Ground||BT2||LRCE||Longitudinal Parity Error|
|BU1||BU2||LRCS||Longitudinal Parity Strobe|
|BV1||MAN CLR L||BV2||Ground|
For the TMA11 and TMB11, delete the "MAN CLR L", and re-name "DEN0" and "DEN1" to "DEN8" and "DEN5" respectively. The encoding of the two density bits is:
|DEN 5||DEN 8||Mode|
|0||0||200 bpi, 7-channel|
|0||1||800 bpi, 7-channel|
|1||0||556 bpi, 7-channel|
|1||1||800 bpi, 9-channel|
TM11 and TMA11 Module Locations
These are the module locations for the TM11:
|Slot||Connector A||Connector B|
@ = Cable
For the TMA11, slot 27B contains an M7854 "OPI/BTE Detector".
|v • d • ePDP-11 Computers and Peripherals|
| Unibus PDP-11s - PDP-11/20 • PDP-11/15 • PDP-11/35 • PDP-11/40 • PDP-11/45 • PDP-11/50 • PDP-11/55 • PDP-11/70 • PDP-11/05 • PDP-11/10 • PDP-11/34 • PDP-11/04 • PDP-11/44 • PDP-11/60 • PDP-11/24 • PDP-11/84 • PDP-11/94
Clones: CM 1420