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NEANDER AP-1971 8-bit accumulator — the starting point.
- WIDTH
- 8 bit
- OPCODES
- 11
- MEMORY
- 256 B
One accumulator, three flags, 11 opcodes. The simplest Weber machine — made to teach fetch / decode / execute.
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AHMES AP-1973 Neander, extended — shifts, rotates, arithmetic.
- WIDTH
- 8 bit
- OPCODES
- 24
- FLAGS
- N Z V C B
Adds carry, borrow, overflow, unsigned compares, and bit-shift instructions. Still one accumulator, still 256 bytes.
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RAMSES AP-1985 Three registers, four addressing modes.
- WIDTH
- 8 bit
- REGS
- RA · RB · RX
- MODES
- 4
RA / RB / RX, immediate / direct / indirect / indexed. Introduces JSR self-linking and real operand encoding in the IR.
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CESAR AP-1991 16-bit, eight registers, 64 KiB, memory-mapped I/O.
- WIDTH
- 16 bit
- MEMORY
- 64 KiB
- MODES
- 8
Eight 16-bit registers (R6=SP, R7=PC), eight addressing modes, display + keyboard at the top of memory. The family's flagship.