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[HP 71B] Software for FRAM71 users
02-06-2017, 09:26 PM
Post: #28
RE: [HP 71B] Software for FRAM71 users
(02-05-2017 10:09 PM)Dave Frederickson Wrote:  That does appear to be the case, but where is that written?

I didn’t see it written until I did in post#25.

(02-05-2017 10:09 PM)Dave Frederickson Wrote:  It appears the HP-IL module is always configured on a 32k boundary. I wonder why that is?

According to the rules we talk about, HP-IL ROM is always in a 16k boundary which can be addresses X0000 to X7FFF or X8000 to XFFFF but because HP-IL is lower in port number it gets its address attributed before others 16k or less chips, at X0000 and if there isn’t another 16k or less ROM/IRAM the next 16k boundary at X8000 to XFFFF cannot be filled (the loss of address space can be lower if HP-IL address is at F0000).
As passionate as you are about it, you probably already figure that out by now.

(02-05-2017 05:07 PM)Dave Frederickson Wrote:  If we're "flirting with the limits" then we need to know not just how much address space is left, but whether that space is RAM or ROM, as demonstrated in the previous post.

I’m having others matters to attend to for at least 3 weeks, but will look into it, when the time comes, if you really think that’s necessary. I will see if I can come up with a implementation compatible with the requirements (or, maybe a “Dave’ Special Sport Edition” of MEMDIS…? Chips size can also be useful information to anticipate next configuration).

(02-05-2017 01:27 AM)rprosperi Wrote:  
(02-05-2017 12:14 AM)dayd Wrote:  The IDS is pretty vague about the algorithm used in the configuration phase.

Indeed! "pretty vague" is about as positive a comment as one can make. I've found that to get anything useful out of reading the IDS, one needs to read the relevant portions many times, plus any/all related areas. It's a lot like Unix/Linux docs - it makes perfect sense if you already understand it.

For more info on 71B memory configuration, read this article:

Lol, I agree, I couldn’t help myself and quoted the IDS (post#25) with a phrase that get me a bit nervous at the time…
Thank you for the link, that’s very useful information for those who read this thread looking for more insight.
By the way, IDS refers here to the Software Internal Design Specification for the HP-71 volumes that can be found in the Museum Document Sets

Best regards, André
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[HP 71B] Software for FRAM71 users - dayd - 02-01-2017, 10:17 PM
RE: [HP 71B] Software for FRAM71 users - dayd - 02-06-2017 09:26 PM

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