Great suggestion Richard ! When I used the code below, x & y seem to increment to high values without errors. At a timer tick, there is a switch between increment_x_task & increment_y_task !
IRQ_Handler
LDR r10, =LPC_BASE_VIC ; Sid - 2022.02.11 - Assuming r10 is rarely used
LDR pc , [r10, #VIC_VectAddr]
Now, I’ll enable the UART interrupt, restore its ISR & see how that goes ! If it works, I’ll start bringing in other tasks from the FreeRTOS main() function one by one !