Changes
CRTC
,This table lists the known ICs used, with their part number, manufacturer and type number.
{|{{Prettytable|width: 700px; font-size: 2em;}}|''Part number ''||''Manufacturer ''||''Type number (note 3) ''|-|UM6845 ||UMC ||0 |-|HD6845S ||Hitachi ||0 |-|UM6845R ||UMC ||1 |-|MC6845 ||Motorola ||2 |-|AMS40489 ||Amstrad ||3 (note 1) |-|??? ||Amstrad? ||4 (note 2) |}
'''NOTES'''
As far as I know, the type number system was originally used by demo programmers.
In most cases, the type of the detected 6845 is reported.
4. As far as I know, the KC compact used HD6845S only.
The 6845 is selected when bit 14 of the I/O port address is set to "0". Bit 1 and 0 of the I/O port address define the function to access. The remaining bits can be any value, but it is adviseable to set these to "1" to avoid conflict with other devices in the system.