02-07-2023, 05:28 PM
Hi John,
There were four versions of the "below Mainboard" colour add-on's.
MB1217 - Standard (original)
MB1217 - Analog (fuse in the ground line to pin 14/15 of the D15 output connector) also a three level (analog RGB) output was added to pins 13,11 & 12.
MB1217 -3-01 The fuse was moved to the +5 Volt line instead of the ground and the fused +5 Volt was routed to Pin 9 of the D15 output connector.
MB1217 -4 01 The final version before the Microbee design moved to the Premium mainboard which integrated the Colour onto the Main board. This version was designed to work with the MB1248 Rev6 Mainboard.
As this new mainboard had a Deglitch circuit integrated into it's design, the deglitch circuit was dropped from the last Colour adapter board reducing the parts count and the number of interconnections between the two boards.
All four of these diagrams should be in the schematics section of the Repository.
Ernest
There were four versions of the "below Mainboard" colour add-on's.
MB1217 - Standard (original)
MB1217 - Analog (fuse in the ground line to pin 14/15 of the D15 output connector) also a three level (analog RGB) output was added to pins 13,11 & 12.
MB1217 -3-01 The fuse was moved to the +5 Volt line instead of the ground and the fused +5 Volt was routed to Pin 9 of the D15 output connector.
MB1217 -4 01 The final version before the Microbee design moved to the Premium mainboard which integrated the Colour onto the Main board. This version was designed to work with the MB1248 Rev6 Mainboard.
As this new mainboard had a Deglitch circuit integrated into it's design, the deglitch circuit was dropped from the last Colour adapter board reducing the parts count and the number of interconnections between the two boards.
All four of these diagrams should be in the schematics section of the Repository.
Ernest