RAMBo board with heated bed

Hello, sorry to ask another question, but I am wondering if anyone has set up a heated bed with a RAMBo board yet. All the firmware works the same except my heated bed is not yet working properly, I am using Marlin firmware and wondering if pin assignments change at all between RAMPS 1.4 and RAMBo

Thanks again,
Joe

Looking at the schematics, the pin assignments are very different. The current version of Marlin supports RAMBo, define motherboard = 301.

Having the same issue here. Rambo board works for hot end, but not heated bed. Checked the configuration.h and MOTHERBOARD =301.

The hot end and heated bed are on different circuits. Make sure that all three power inputs are supplied with 12V.

Also checked configuration.h and have motherboard = 301. I'm thinking the Marlin firmware is missing some code for the heated bed, I copied this over from a previous Marlin I had running with RAMPS 1.4 but still no success.

#ifdef PIDTEMPBED
case 304: // M304
{
if(code_seen('P')) bedKp = code_value();
if(code_seen('I')) bedKi = code_value()*PID_dT;
if(code_seen('D')) bedKd = code_value()/PID_dT;
updatePID();
SERIAL_PROTOCOL(MSG_OK);
SERIAL_PROTOCOL(" p:");
SERIAL_PROTOCOL(bedKp);
SERIAL_PROTOCOL(" i:");
SERIAL_PROTOCOL(bedKi/PID_dT);
SERIAL_PROTOCOL(" d:");
SERIAL_PROTOCOL(bedKd*PID_dT);
SERIAL_PROTOCOLLN("");
}
break;
#endif //PIDTEMP

Figured it out. Thermistor was hooked up to wrong terminal, should be T2 like the RAMPS (which is the third port on the RAMBo board, I was plugging it in the last)

Quote

Thermistor was hooked up to wrong terminal, should be T2 like the RAMPS

This was a key statement for me. Possibly obvious to others, but only after seeing this did I realize that the Marlin firmware will refuse to heat the bed if the thermistor is not readble... So while the thermistor was in the wrong port, no voltage appeared on the heated bed port. Thanks!