[Coco] MyRam vs, Rammer

[L. Curtis Boyle]

There are two pluses in the RAMMER column (at least in the bug fix version in EOU Beta 4) - since it mimics “real”  drive geometry (number of sides, sectors per track, tracks), it works with the BACKUP command (so you can back up real floppies in 1 pass to either direction. 
It also supports the special /MD descriptor (“memory descriptor”) for debugging. This lets you both view and modify memory anywhere in the 2 MB while the system is running. Not for the casual user, but very helpful for testing special cases, error trapping, etc. 

Sent from my iPhone

> On May 12, 2019, at 3:04 PM, Gene Heskett <gheskett at shentel.net> wrote:
> 
>> On Sunday 12 May 2019 03:33:08 pm coco at jechar.ca wrote:
>> 
>>  What are the pros and cons of MyRam vs Rammer for 512K and 2 Meg
>> systems ?
>> 
>>  Charlie.
> 
> From the author of MyRam, not a lot for a 512k system, although bringing 
> it into existence, just access it by any handy command, like a "dir /r0" 
> and it will be formatted and ready to use in about 100 milliseconds and 
> a deiniz /r0 it when done to demolish it and get every byte back for 
> other uses may still be an advantage.  See my README for how to adjust 
> its size in 8 kb chunks. I've used it for c compiler scratchpad set for 
> 1.7 megabytes on my 2 meg machine, probably at least a thousand times. 
> If you don't have a hard drive, it will speed up a compile thats using a 
> floppy for scratchpad a very noticeable amount. With scsi hard drives, 
> and probably even the ide drives, it won't be noticeably faster because 
> the drive is not the speed limit, the coco is. It takes 11 seconds for 
> the coco3 to move a megabyte.  Thats slow considering modern SSD's with 
> a sata interface on a slow atom cpu are doing 120+ megs/second these 
> days.
> 
> example from one of my machine controller boxes, with a 1.4GHz dual core 
> atom cpu:
> gene at shop:~$ sudo hdparm -tT /dev/sda1
> [sudo] password for gene:
> 
> /dev/sda1:
> Timing cached reads:   1808 MB in  2.00 seconds = 904.15 MB/sec
> Timing buffered disk reads: 368 MB in  3.00 seconds = 122.58 MB/sec
> gene at shop:~$
> And thats slow, another machine with more butterfly's in the cpu is doing 
> 192 for that last figure.
> 
> Cheers, Gene Heskett
> -- 
> "There are four boxes to be used in defense of liberty:
> soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Genes Web page <http://geneslinuxbox.net:6309/gene>
> 
> 
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