| AT&T 3B2 Simulator | |
| ================== | |
| This module contains a simulator for the AT&T 3B2 Model 400 microcomputer. | |
| *CAUTION*: The simulator is under active and heavy development. It is | |
| usable today, but please consider this emulator to be a beta. | |
| Devices | |
| ------- | |
| The following devices are simulated. The SIMH names for the simulated | |
| devices are given in parentheses: | |
| - 3B2 Model 400 System Board with 1MB, 2MB, or 4MB RAM (CSR, NVRAM) | |
| - WE32100 CPU (CPU) | |
| - WE32101 MMU (MMU) | |
| - PD8253 Interval Timer (TIMER) | |
| - AM9517 DMA controller (DMAC) | |
| - SCN2681A Integrated DUART (IU) | |
| - TMS2793 Integrated Floppy Controller (IF) | |
| - uPD7261A Integrated MFM Fixed Disk Controller (ID) | |
| Usage | |
| ----- | |
| To boot the 3B2 simulator into firmware mode, simply type: | |
| sim> BOOT CPU | |
| You will be greeted with the message: | |
| FW ERROR 1-01: NVRAM SANITY FAILURE | |
| DEFAULT VALUES ASSUMED | |
| IF REPEATED, CHECK THE BATTERY | |
| FW ERROR 1-02: DISK SANITY FAILURE | |
| EXECUTION HALTED | |
| SYSTEM FAILURE: CONSULT YOUR SYSTEM ADMINISTRATION UTILITIES GUIDE | |
| NVRAM can be saved between boots by attaching it to a file. | |
| sim> ATTACH NVRAM <file> | |
| On subsequent boots, you will instead see the message | |
| SELF-CHECK | |
| FW ERROR 1-02: DISK SANITY FAILURE | |
| EXECUTION HALTED | |
| SYSTEM FAILURE: CONSULT YOUR SYSTEM ADMINISTRATION UTILITIES GUIDE | |
| Once you see the `SYSTEM FAILURE` message, this is actually an | |
| invisible prompt. To access firmware mode, type the default 3B2 | |
| firmware password `mcp`, then press Enter or carriage return. | |
| You should then be prompted with: | |
| Enter name of program to execute [ ]: | |
| Here, you may type a question mark (?) and press Enter to see a list | |
| of available firmware programs. | |
| Booting UNIX SVR3 | |
| ----------------- | |
| UNIX SVR3 for the 3B2 partially boots. To boot UNIX, attach the first | |
| disk image from the 3B2 "Essential Utilities" distribution. | |
| sim> ATTACH IF <disk-image> | |
| sim> BOOT CPU | |
| Once you reach the `SYSTEM FAILURE` message, type `mcp` to enter | |
| firmware mode. When prompted for the name of a program to boot, enter | |
| `unix`, and confirm the boot device is `FD5` by pressing Enter or | |
| carriage return. | |
| Enter name of program to execute [ ]: unix | |
| Possible load devices are: | |
| Option Number Slot Name | |
| --------------------------------------- | |
| 0 0 FD5 | |
| Enter Load Device Option Number [0 (FD5)]: | |
| Installing SVR3 | |
| --------------- | |
| To install SVR3 to the first hard disk, first, attach a new image | |
| sim> ATTACH ID0 <disk-image> | |
| Then, boot the file `idtools` from the "3B2 Maintenance Utilities - | |
| Issue 4.0" floppy diskette. | |
| From `idtools`, select the `formhard` option and low-level format | |
| integrated disk 0. Parameters are: | |
| Drive Id: 5 | |
| Number cylinders: 925 | |
| Number tracks/cyl: 9 | |
| Number sectors/track: 18 | |
| Number bytes/sector: 512 | |
| After low-level formatting integrated disk 0, boot the file `unix` | |
| from the first diskette of the 3B2 "Essential Utilities" distribution, | |
| and follow the prompts. |