okaaay, so to solve the problem with RAMBOv1.2g boards not working properly i've bypassed the two voltage divider circuits for heater and hotend, and created equivalents from components that i had immediately to hand:
[attachment 75672 IMG_0038.png]
the dog's dinner on a 3x2 header with four resistors and two capacitors is a replacement pair of voltage dividers plugged into X-40. i've modified pins.h so that it uses ADC3 and ADC4, and i'm getting temperature readings of 20.3 and 20.4C as a result.
what we can conclude from this - especially given that all four thermistor circuits are wrong - is that the most likely fault on the RAMBOv1.2g board is the OVREF circuit. however as i have a solution - messy or not - i'm calling "time" on this one as i have so much else to get done. if anyone else encounters incorrect temperature readings with a RAMBOv1.2g please do speak up.
[attachment 75672 IMG_0038.png]
the dog's dinner on a 3x2 header with four resistors and two capacitors is a replacement pair of voltage dividers plugged into X-40. i've modified pins.h so that it uses ADC3 and ADC4, and i'm getting temperature readings of 20.3 and 20.4C as a result.
what we can conclude from this - especially given that all four thermistor circuits are wrong - is that the most likely fault on the RAMBOv1.2g board is the OVREF circuit. however as i have a solution - messy or not - i'm calling "time" on this one as i have so much else to get done. if anyone else encounters incorrect temperature readings with a RAMBOv1.2g please do speak up.