??? 03/02/05 20:02 Read: times |
#88910 - Much simpler Responding to: ???'s previous message |
First forget the separate stack space. That was not my idea and I don't really like it. Second, forget the RD2 et al. paradigm of "internal external" memory (XRAM). There is internal RAM inside the chip (being it 256B, 1kB, 8kB, 64kB or whatever) fullstop. External memory is what isoutside, RAM, ROM, FLASH, anything. The lower 128B of internal ram is accessed as usual - direct, indirect; bitwise, implied where appropriate. Internal RAM above 128B (including above 256B) is accessed only using mov @Ri. Push and pop works over entire internal RAM. External data memory is accessed using movx @dptr, or movx @Ri, where the upper address is given (and strongly driven) by RiH. Is it KISS enough? Compatibility switch - if even needed - is only one bit and can be implemented in any SFR. Jan Waclawek PS. Pandora was a relative of Prometheus (his brother's wife), who created mankind and gave them fire and knowledge. For doing this, he was punished by gods. Good and bad go hand in hand... |