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Pdp11 Boot proms

Pdp11 Boot proms

Boot proms and types

82S131
Am27S13
63S241
74S571
(512x4-TS)
&
82S129
(256x4-TS)
(DL) RL01/02 cartridge disk 23-751A9 0x0698 SRC
LST
(1,2)
(DM) RK06/07 cartridge disk 23-752A9 0x0627 SRC
LST
(1,2)
(DX) RX01 floppy disk, single density 23-753A9 0x066D SRC
LST
(2)
(DP) RP02/03 cartridge disk
(DB) RP04/05/06,RM02/03/05 cartridge disk
23-755A9 0x0622 SRC
LST
(1,2)
(DK) RK03/05 DECdisk
(DT) TU55/56 DECtape
23-756A9 0x0613 SRC
LST
(1,2)
(MM) TU16/45/77,TE16 magtape 23-757A9 0x06F2 SRC
LST
(1,2)
(MT) TS03,TU10,TE10 magtape 23-758A9 0x06DC SRC
LST
(1,2)
(DS) RS03/04 fixed disk 23-759A9 0x04BC SRC
LST
(2)
(TT) ASR33 lowspeed reader
(PR) PC05 hispeed reader
23-760A9 0x0681 SRC
LST
(1,2)
(CT) TU60 DECcassette 23-761A9 0x05E2 SRC
LST
(2)
(RS) RS11/64 fixed disk 23-762A9 - - (4)
(CR) CR11 card reader 23-763A9 - - (4)
(MS) TS04/11,TU80,TSU05 tape 23-764A9 0x06E1 SRC
LST
(2)
(DD) TU58 DECtapeII 23-765A9 0x0603 SRC
LST
(2)
(DD) TU58 DECtapeII; fixes non-std CSR access 23-765B9 0x05BC SRC
LST
(5)
(DU) MSCP UDA50(RAxx) disk 23-767A9 0x0677 SRC
LST
(1)
(DY) RX02 floppy disk, double density 23-811A9 0x0646 SRC
LST
(1,2)
(MU) TMSCP TK50,TU81 magtape 23-E39A9 0x0705 SRC
LST
(1)
(XE) Ethernet DEUNA/DELUA Net Boot (v1) 23-E22A9 - - (4)
(XE) Ethernet DEUNA/DELUA Net Boot (v2) 23-E32A9 0x05D6 SRC
LST
(1)
23-E33A9 0x0755 SRC
LST
(XM) DECnet DDCMP DMC11/DMR11 23-862A9 0x0625 SRC
LST
(1,2)
23-863A9 0x063F SRC
LST
23-864A9 0x0551 SRC
LST
(XU) DECnet DDCMP DU11 23-865A9
23-866A9
23-867A9
- - (4)
(XW) DECnet DDCMP DUP11 23-868A9
23-869A9
23-870A9
- - (4)
(XL) DECnet DDCMP DL11-E 23-926A9
23-927A9
23-928A9
- - (4)
(ZZ) Test ROM; runs diagnostics continuously

Creating a boot PROM

Getting the PROMs to burn is a bit challenging, as is getting a device to burn them.. I was very lucky to get an old PROM burner: a Stag Quasar Plus. This comes with Windows XP software that knows a lot of types and which also contains really a lot of older types.

Getting the PROMs themselves was a bit harder.. These devices are old, and not easy to get. The usual route is Ebay, and my first attempt got me 10 MH74S571 proms in two weeks, which according to the number should work. But they did not: this manufacturer Tesla) only made them read compatible, writing them uses a different mechanism than all the others. Sigh.

The next attempt was a set of AM27S13 PROMs from Spain. They arrived by snail three weeks later. That is: the envelope arrived, with a nice thank you note for the order - but without PROMs. They had forgotten to put them in the envelope, so yet another three weeks to wait.

Then I got lucky: I actually found a Dutch shop (I live in the Netherlands part-time) which sold 82S129 PROMs for a sweet price - and these finally arrived… And worked

I now have an extra boot PROM for the TU58:

CZM9BE0 M9312/1144 UBI BOOT

DIAG. ROM (E20) (FOR 11-44 UBI: E58)C0

BOOTSTRAP ROM ENTRY POINTS AND DEVICE CODES
LOC.             NO DIAG.       RUN DIAG.       DEVICE CODE

ROM 1(E48)      173004          173006          MS
ROM 2(E49)      173204          173206          DL
ROM 3(E50)      173404          173406          DD

PSEUDO POWER-FAIL VECTOR ADR./NEW PC    173024  173052
ROM SEQUENCE IS INCORRECT AS PER INSTALLATION PROCEDURE.

SEQUENCE SHOULD BE:

ROM 1(E48)      DD
ROM 2(E49)      DL
ROM 3(E50)      MS

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© 2024 by Frits Jalvingh. All information in here can be freely used (MIT License)