FRAM71B

[Dave Frederickson]

(01-24-2017 07:33 PM)Hans Brueggemann Wrote:  

(01-24-2017 04:34 PM)Dave Frederickson Wrote:  Hi Hans,

How was I able to FREEPORT the device and load the 64k Data Acq Module into F-Blocks 0 & 1 without enabling SYSRAM Write (CN2-4)? Consider that I use ROMCOPY to load a ROM image into an IRAM and that I only use CN2-4 when POKEing an alternate O/S or the Diag ROM into SYSRAM.
http://hpmuseum.org/forum/thread-6287-po...l#pid63381

The LEDs on my modules are quite visible so I would have noticed if I had inadvertantly moved the jumper.

Regards Dave

i have no clue. when doing
POKE"2C000","909100"
OFF/ON
POKE"30000","CAFE"
PEEK$("2C000",4),
the result is indeed "0000", as expected when CN2-4 is not set.
then,
set CN2-4
POKE"30000","CAFE"
clear CN2-4
PEEK$("2C000",4),
gives "CAFE", again, as expected.
also, a FREEPORT(5) exits silently, but doesn't overwrite any contents in F_0x00000 and also doesn't reduce MEM. so, on my FRAM71B, CN2-4 seems to work as advertized.

i'm running HW105_V607 (like all FRAM71Bs out there). can you do a quick check with above code on your module? just switch over to TOP FRAM in order not to spoil your BOT configuration.

Hi Hans,

POKE"2C000","109100" > Okay. A little different because I want a 64k IRAM.
ON/OFF > Okay. Reports around 83k RAM.
POKE"30000","CAFE" > Okay.
PEEK$("30000",4) > Gives "8D72", not "CAFE". Expected behavior.
SET CN2-4
POKE"30000","CAFE" > Okay.
PEEK$("30000",4) > Gives "CAFE".

FREEPORT(5) works as expected.
Remove CN2-4 and PORT(5) is write-protected as expected.

Now here's the embarrassing part, did I really copy the Data Acq ROM to the IRAM? That configuration is lost and now I'm not so sure.

In any case, thanks, Hans, for the reminder about write protection on Banks 0 and 1.

Regards, Dave