There are several articles in Go64 detailing the wait stating necessary. SIMMs are only used for the extra memory on the expansion board which goes up to 16MB. Wait states can be as long as 8cycles. Most of the time reads are from fast SRAM for the standard 64k and the extra 64k which shadows the roms. The write cycles to the C64 are DMA based... As some might know, i've been playing around with a core-emulator for the PC in the hope of getting it be the 6510... To prove how valuable selective mirroring is, consider this. If all is mirrored, the emulator slows to 1.3MHz on K6-2/500 PC, If page 0 and page 1 are not mirrored, the core emulator runs at 40MHz. If nothing is mirrored, the core will run at 66MHz. (tests done with the bas-test program distributed with C64s). The problem for the PC is ofcourse ISA I/O bus writes needed for transfering data to/from the C64. - Nick PLEASE TAKE NOTE: The contents of this email (including any attachments) may be privileged and confidential. Any unauthorised use of the contents is expressly prohibited. If you have received this email in error, please advise us immediately (you can contact us by telephone on +61 8 9441 2311 by reverse charge) and then permanently delete this email together with any attachments. We appreciate your co-operation. Whilst Orbital endeavours to take reasonable care to ensure that this email and any attachments are free from viruses or other defects, Orbital does not represent or warrant that such is explicitly the case (C) 2000: Orbital Engine Company (Australia) PTY LTD and its affiliates - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tml.hut.fi.
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