VAXstation 100 firmware notes: Difference between revisions
From Computer History Wiki
Jump to navigationJump to search
Keyboard test. |
mNo edit summary |
||
| Line 24: | Line 24: | ||
The firmware transmits code FD (hex) to the LK201 keyboard, which commands it to jump to the power-up sequence and self-test. The keyboard transmits a four-byte message back. The VS100 ignores the keyboard ID, and checks that the third is not 3D. | The firmware transmits code FD (hex) to the LK201 keyboard, which commands it to jump to the power-up sequence and self-test. The keyboard transmits a four-byte message back. The VS100 ignores the keyboard ID, and checks that the third is not 3D. | ||
This information is from the VT220 Technical Manual. | This information is from the VT220 Technical Manual.<br> | ||
[[Image:LK201-powerup.png]] | [[Image:LK201-powerup.png]] | ||
Revision as of 19:14, 11 February 2023
Random notes from running the firmware in an emulator.
Memory map
Error LEDs
Indicates which test failed. During power-up, green light turned off. During idle loop, green light remains on.
Apparently there's a bug.
Interrupts
All VS100 interrupts use the autovector feature.
Keyboard test
The firmware transmits code FD (hex) to the LK201 keyboard, which commands it to jump to the power-up sequence and self-test. The keyboard transmits a four-byte message back. The VS100 ignores the keyboard ID, and checks that the third is not 3D.
This information is from the VT220 Technical Manual.
D0 flags
The firmware maintains a set of flags in register D0.
| Bit (decimal) | Meaning |
| 16 | Manufacturing mode. |
| 19 | Power-up error. |
| 24 | BBA done. |
| 25 | Vertical retrace interrupt. |
