The intel 4004 Processor

This processor is commonly seen as the first microprocessor. It is a 4 bit processor which means its registers are commonly 4 bits wide (with grouping 8 and 12 bits for larger data can be achieved). Unfortunately, information is scarce, so I focused development around a few documents, such as:

http://bitsavers.trailing-edge.com/components/intel/MCS4/MCS-4_Assembly_Language_Programming_Manual_Dec73.pdf

http://datasheets.chipdb.org/Intel/MCS-4/datashts/intel-4004.pdf

For this processor, I had to add the generic bit size to allow 4-bit memory. Also, some of the concepts such as the RAM status flags need to be embedded into the system.