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HP-48 FRAM Cards
08-17-2016, 09:38 AM (This post was last modified: 08-18-2016 08:02 AM by matthiaspaul.)
Post: #38
RE: HP-48 FRAM Cards
(08-10-2016 01:54 PM)JDW Wrote:  I also asked him about performance. He said that while FRAM is MUCH faster than the old SRAM cards that need batteries, the 48GX limits performance such that the FRAM card is only about 20-30% faster than the SRAM cards. But honestly, that's not bad at all; and to top it off, you never need a battery for the FRAM card.
I haven't looked this up, but AFAIR the HP48 uses parallel asynchronous SRAM. If so, there's no feedback from the memory chip to the processor to indicate that the requested data is available or has been written successfully. Instead, the processor uses a fixed timing to access the memory and the memory has to be chosen just to be fast enough to fit into that timing. If it is too slow, obviously bad things will happen, but if the memory is faster than necessary, the processor will never know and therefore cannot take advantage of it.

You could take advantage of it, if you'd overclock the processor, but this will throw over the timing with other peripherals.

If the processor has configuration registers for the memory timing, it might be possible to reprogram the timing to become faster, but the processor won't do this by itself.

Greetings,

Matthias


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Messages In This Thread
HP-48 FRAM Cards - JDW - 07-16-2016, 02:59 AM
RE: HP-48 FRAM Cards - Dave Frederickson - 07-16-2016, 04:15 AM
RE: HP-48 FRAM Cards - JDW - 07-16-2016, 04:21 AM
RE: HP-48 FRAM Cards - matthiaspaul - 07-16-2016, 04:39 PM
RE: HP-48 FRAM Cards - Dave Frederickson - 07-16-2016, 09:18 PM
RE: HP-48 FRAM Cards - Michael Lopez - 07-16-2016, 07:07 AM
RE: HP-48 FRAM Cards - cruff - 07-16-2016, 12:20 PM
RE: HP-48 FRAM Cards - JDW - 07-16-2016, 12:24 PM
RE: HP-48 FRAM Cards - JDW - 07-17-2016, 09:23 AM
RE: HP-48 FRAM Cards - snrowe - 07-23-2016, 12:03 AM
RE: HP-48 FRAM Cards - JDW - 07-23-2016, 12:19 AM
RE: HP-48 FRAM Cards - snrowe - 07-23-2016, 12:51 AM
RE: HP-48 FRAM Cards - JDW - 07-23-2016, 12:58 AM
RE: HP-48 FRAM Cards - snrowe - 07-23-2016, 01:04 AM
RE: HP-48 FRAM Cards - Dave Frederickson - 07-23-2016, 01:40 AM
RE: HP-48 FRAM Cards - snrowe - 07-23-2016, 02:37 AM
RE: HP-48 FRAM Cards - Sylvain Cote - 07-23-2016, 02:45 AM
RE: HP-48 FRAM Cards - matthiaspaul - 07-23-2016, 05:10 PM
RE: HP-48 FRAM Cards - JDW - 07-23-2016, 10:56 PM
RE: HP-48 FRAM Cards - matthiaspaul - 07-24-2016, 02:28 AM
RE: HP-48 FRAM Cards - Dave Frederickson - 07-24-2016, 04:29 PM
RE: HP-48 FRAM Cards - matthiaspaul - 07-24-2016, 06:52 PM
RE: HP-48 FRAM Cards - Dave Frederickson - 07-23-2016, 12:46 AM
RE: HP-48 FRAM Cards - snrowe - 07-23-2016, 01:00 AM
RE: HP-48 FRAM Cards - Dave Frederickson - 07-23-2016, 01:22 AM
RE: HP-48 FRAM Cards - snrowe - 07-23-2016, 01:35 AM
RE: HP-48 FRAM Cards - JDW - 07-23-2016, 02:01 AM
RE: HP-48 FRAM Cards - JDW - 07-23-2016, 02:57 AM
RE: HP-48 FRAM Cards - snrowe - 07-23-2016, 03:14 AM
RE: HP-48 FRAM Cards - JDW - 07-23-2016, 03:50 AM
RE: HP-48 FRAM Cards - Dave Frederickson - 07-23-2016, 03:53 AM
RE: HP-48 FRAM Cards - JDW - 08-10-2016, 01:54 PM
RE: HP-48 FRAM Cards - matthiaspaul - 08-17-2016 09:38 AM
RE: HP-48 FRAM Cards - JDW - 08-16-2016, 01:56 AM
RE: HP-48 FRAM Cards - matthiaspaul - 08-18-2016, 09:56 AM
RE: HP-48 FRAM Cards - JDW - 08-19-2016, 12:06 AM
RE: HP-48 FRAM Cards - Dave Frederickson - 08-19-2016, 12:20 AM
RE: HP-48 FRAM Cards - JDW - 08-19-2016, 12:32 AM
RE: HP-48 FRAM Cards - Dave Frederickson - 08-19-2016, 02:15 AM
RE: HP-48 FRAM Cards - matthiaspaul - 08-20-2016, 11:52 AM
RE: HP-48 FRAM Cards - Ron Ross - 08-16-2016, 01:04 PM
RE: HP-48 FRAM Cards - JDW - 08-16-2016, 01:27 PM
RE: HP-48 FRAM Cards - Ron Ross - 08-16-2016, 04:14 PM
RE: HP-48 FRAM Cards - JDW - 08-16-2016, 11:43 PM
RE: HP-48 FRAM Cards - JDW - 08-19-2016, 02:21 AM
RE: HP-48 FRAM Cards - JDW - 08-21-2016, 11:44 PM
RE: HP-48 FRAM Cards - Han - 08-22-2016, 04:10 PM
RE: HP-48 FRAM Cards - matthiaspaul - 08-22-2016, 07:32 PM
RE: HP-48 FRAM Cards - gege - 08-25-2016, 03:19 PM
RE: HP-48 FRAM Cards - matthiaspaul - 08-25-2016, 07:38 PM
RE: HP-48 FRAM Cards - JDW - 08-25-2016, 11:52 PM
RE: HP-48 FRAM Cards - Ron Ross - 08-26-2016, 04:13 PM
RE: HP-48 FRAM Cards - matthiaspaul - 08-27-2016, 11:32 AM
RE: HP-48 FRAM Cards - JDW - 08-27-2016, 12:21 AM
RE: HP-48 FRAM Cards - gege - 08-27-2016, 09:36 AM
RE: HP-48 FRAM Cards - JDW - 08-29-2016, 12:21 AM
RE: HP-48 FRAM Cards - gege - 08-29-2016, 05:32 AM
RE: HP-48 FRAM Cards - JDW - 08-29-2016, 05:35 AM
RE: HP-48 FRAM Cards - gege - 08-29-2016, 05:36 AM
RE: HP-48 FRAM Cards - Han - 03-23-2017, 02:45 PM
RE: HP-48 FRAM Cards - Hans Brueggemann - 03-23-2017, 06:44 PM
RE: HP-48 FRAM Cards - Chris Dreher - 03-23-2017, 04:06 PM
RE: HP-48 FRAM Cards - EugeneNine - 03-23-2017, 04:58 PM
RE: HP-48 FRAM Cards - JDW - 03-23-2017, 11:54 PM
RE: HP-48 FRAM Cards - EugeneNine - 03-24-2017, 12:11 PM
RE: HP-48 FRAM Cards - Gary Cray - 07-16-2017, 06:47 PM



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