[SOLVED] Keyboard inop at POST/BIOS

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henderson_bay329
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[SOLVED] Keyboard inop at POST/BIOS

Post by henderson_bay329 »

Hello.

Today, I received a Lagrande C2G PS2F to USBM adapter so that I can use an HP keyboard (preferred) on my Dell Optiplex 755 SFF desktop. I put the adapter onto the keyboard cable and connected to the same USB port I had the Dell keyboard on, and then booted the system. When prompted for the boot password, I found that no alpha-numeric keys showed on the display. The NUMLOCK light was off (I have BIOS set to NUMLOCK <On> at boot). I did find later that the system at boot time responded to the ENTER key on the Dell keyboard, but only that key, also that the NUMLOCK light was on.

I think I did an update before I shut it down (late) last night, so this would be the first boot after the update. I did not capture a Timeshift before the update (note I can't get into the system currently to restore without the keyboard!). The system information presented below is not fully up to date - it's from Jan 3 2024 when I initially got this system running. Certainly the BIOS is newer, I think A24. The Linux Kernel is likely to be 5.4.0-172 or close with last night's update (that's the latest on my laptop, similarly updated).

So far, I have tried this list of actions, no joy:
1. unplug/replug keyboard
2. reinstall original Dell keyboard
3. unplug power, replug power, try to boot
a. with original keyboard
b. with HP keyboard
4. remove USB and Enet cables and power cord, reinstall power cord, power on, install keyboard and mouse.
5. try all the USB ports
6. Tried to boot from an external SATA drive, which is in the boot order preceding the internal SSD

I will research a bit then likely carry out a CMOS reset as my next attempt to fix this.
[SOLUTION EDIT: CMOS + password reset via MoB jumpers fixed. I replicated the problem after the CMOS reset, then reset again.]

Anybody know what might be going on? Did the adapter maybe fry the USB subsystem somehow?
[SOLUTION EDIT: Researching, I learned that PS2 and USB keyboards use fundamentally different I/O schemes, so a "PS2-USB" adapter in this case was worthless. I don't know exactly why plugging in the "adapted" keyboard would affect the BIOS and or POST as it did, requiring the CMOS reset to correct. Conclusion - Dell Optiplex 755 requires USB keyboard and mouse, unless you maybe could do an elaborate workaround through the legacy serial ports; IMO it's not worth the effort.]

Thanks in advance.

Code: Select all

System:    Kernel: 5.4.0-169-generic x86_64 bits: 64 compiler: gcc v: 9.4.0 
           Desktop: Cinnamon 5.2.7 wm: muffin dm: LightDM Distro: Linux Mint 20.3 Una 
           base: Ubuntu 20.04 focal 
Machine:   Type: Desktop System: Dell product: OptiPlex 755 v: N/A serial: <filter> Chassis: 
           type: 15 serial: <filter> 
           Mobo: Dell model: 0PU052 serial: <filter> BIOS: Dell v: A09 date: 03/11/2008 
CPU:       Topology: Dual Core model: Intel Core2 Duo E8200 bits: 64 type: MCP arch: Penryn rev: 6 
           L2 cache: 6144 KiB 
           flags: lm nx pae sse sse2 sse3 sse4_1 ssse3 vmx bogomips: 10640 
           Speed: 2509 MHz min/max: N/A Core speeds (MHz): 1: 2509 2: 2499 
Graphics:  Device-1: AMD RV610 [Radeon HD 2400 PRO/XT] vendor: Dell Optiplex 755 driver: radeon 
           v: kernel bus ID: 01:00.0 chip ID: 1002:94c1 
           Display: x11 server: X.Org 1.20.13 driver: ati,radeon unloaded: fbdev,modesetting,vesa 
           resolution: 1360x768~60Hz 
           OpenGL: renderer: AMD RV610 (DRM 2.50.0 / 5.4.0-169-generic LLVM 12.0.0) 
           v: 3.3 Mesa 21.2.6 compat-v: 3.0 direct render: Yes 
Audio:     Device-1: Intel 82801I HD Audio vendor: Dell Optiplex 755 driver: snd_hda_intel 
           v: kernel bus ID: 00:1b.0 chip ID: 8086:293e 
           Sound Server: ALSA v: k5.4.0-169-generic 
Network:   Device-1: Intel 82566DM-2 Gigabit Network vendor: Dell OptiPlex 755 driver: e1000e 
           v: 3.2.6-k port: ecc0 bus ID: 00:19.0 chip ID: 8086:10bd 
           IF: enp0s25 state: up speed: 100 Mbps duplex: full mac: <filter> 
Drives:    Local Storage: total: 232.83 GiB used: 7.38 GiB (3.2%) 
           ID-1: /dev/sda vendor: Seagate model: ST3250310AS size: 232.83 GiB speed: 3.0 Gb/s 
           serial: <filter> 
Partition: ID-1: / size: 28.67 GiB used: 7.23 GiB (25.2%) fs: ext4 dev: /dev/sda1 
           ID-2: /home size: 194.47 GiB used: 148.2 MiB (0.1%) fs: ext4 dev: /dev/sda2 
           ID-3: swap-1 size: 4.88 GiB used: 0 KiB (0.0%) fs: swap dev: /dev/sda3 
Sensors:   System Temperatures: cpu: 37.0 C mobo: N/A gpu: radeon temp: 57 C 
           Fan Speeds (RPM): N/A 
Repos:     No active apt repos in: /etc/apt/sources.list 
           Active apt repos in: /etc/apt/sources.list.d/official-package-repositories.list 
           1: deb http: //packages.linuxmint.com una main upstream import backport
           2: deb http: //mirrors.accretive-networks.net/ubuntu focal main restricted universe multiverse
           3: deb http: //mirrors.accretive-networks.net/ubuntu focal-updates main restricted universe multiverse
           4: deb http: //mirrors.accretive-networks.net/ubuntu focal-backports main restricted universe multiverse
           5: deb http: //security.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
           6: deb http: //archive.canonical.com/ubuntu/ focal partner
Info:      Processes: 195 Uptime: 16m Memory: 1.89 GiB used: 793.3 MiB (41.0%) Init: systemd 
           v: 245 runlevel: 5 Compilers: gcc: 9.4.0 alt: 9 Client: Unknown python3.8 client 
           inxi: 3.0.38 
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