First keyboards with an XT interface. There is no keyboard controller, no commands to the keyboard. On a modern computer these will usually yield "keyboard error" or "KB/interface error" or some such, but sometimes they can be used nevertheless.
The IBM PC (all models) and the IBM XT (models 68, 78, 86, 87, 88, 267, 277) came with this 83-key keyboard. The IBM AT (models 68, 99, 239, 319) came with an 84-key keyboard. The IBM XT (models 89, 268, 278, 286) and the IBM AT model 339 came with a 101-key keyboard.
The original IBM 83-key PC/XT keyboard did not have LEDs. The original IBM 84-key AT keyboard has LEDs, separates the keypad from the main area, moves the Esc key to the right, and adds the SysReq key. The original IBM 101-key keyboard moves the ten function keys from the left to the top row and adds two more. The Esc key is moved in front of this row of function keys. The "number" and "cursor" functions of the keypad are separated. There are duplicate Ctrl and Alt keys.
The XT keyboard has 83 keys, nicely numbered 1-83, that is, with scancodes 01-53. No escaped scancodes.
This Victor keyboard is very similar. The keypad is separated here, and the Esc key has been moved to the keypad. The frontside of the ScrollLock key says Break. It resembles an AT keyboard but has only 83 keys, the SysRq is still missing.
The Telerate keyboard was used for financial applications, as is clear from the keycaps. This keyboard (in the old XT version, without e0 prefixes) has four additional keys, with scancodes 61, 62, 63, 64. The F11 and F12 keys have scancodes 54 and 55 (instead of the common 57 and 58). There are two LEDs (for CapsLock and NumLock).
Also with an XT interface this NCR keyboard, still with ten function keys on the left, but already with a separate block of keys between the ordinary keys and the numeric keypad. This middle block has on top five keys Ctrl (1d, same as the Ctrl on the left), Del (53, same as Keypad-Del/.), PgUp (49, same as Keypad-9/PgUp), End (4f, same as Keypad-1/End), PgDn (51, same as Keypad-3/PgDn), and below five cursor keys (48, same as Keypad-8/Up; 4b, same as Keypad-4/Left; 47, same as Keypad-7/Home; 4d, same as Keypad-6/Right; 50, same as Keypad-2/Down). Enter and Keypad-enter are both 1c. Below the Enter key PrtScn/* (37), and below that again Ins (52, same as Keypad-0/Ins). CapsLock and NumLock have a built-in LED.
According to FreeKEYB/kbdinfo.html this keyboard has five additional keys with scancodes 55 (F11), 56 (F12), 57 (F13), 58 (F14), 59 (F15).