Roland JP-4 & Promars Main CPU Chip 8048-012

Description A common failure with the Jupiter 4 and Promars are the Mask ROM CPU Chips.  Unfortunately because these Mask ROM CPUs have the firmware on the chip, you can’t just pop in a generic MCS-48 (8048) CPU chip and be up and running.  This replacement chip is a drop in CPU replacement with the firmware on board for the main CPU found on the motherboard of the synthesizer.  All JP-4 and Promars owners would be wise to keep one of these on hand as part of a “Survival Kit”. Related