EEPROM - the Holy Grail of Sideways Rom?

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1024MAK
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby 1024MAK » Mon Jan 25, 2016 4:13 am

Well, if you are in the UK, I should have one or two you can buy at cost price plus postage :D

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby SteveF » Mon Jan 25, 2016 9:44 am

Cheers, if the ones I've ordered from ebay turn up and are the wrong type I'll be in touch!

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Sat Jan 30, 2016 12:13 am

@ Wookie - Are you able to test EELOAD under ADFS without the EEPxx tools? I ask because I've rebuilt an ADFS-compatible EELOAD (assumes PAGE=$1D00) but I haven't done the EEPxx utils yet (although I will in the next day or so). I've attached the new version (3.0A) below on .adf and .ssd images because I'm not sure how you'll get the file onto a real ADFS disc?

I've only tested it under BeebEm using SWR because I don't have an ADFS-equipped machine handy (I think they're all low-down in the compost bin) so it'd be good if you could test EELOAD on real hardware with a real EEPROM for me?

Ta 8)

EDIT : See further down thread for latest downloads.
Last edited by MartinB on Mon Aug 29, 2016 7:13 am, edited 1 time in total.

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Wookie » Sat Jan 30, 2016 7:15 pm

:evil: ](*,) ](*,) ](*,)

Well it's like this, after 30 years loyal service my Elk is misbehaving, it's not seeing my SRAM then it suddenly finds it, it claims EEPROM is ROM then it suddenly sees it as EEPROM and then works just fine ](*,)

I've tried with my original AP2 rom and with DaveH new AP6 rom but it's just the same, I've tried your original utils from DFS that previously worked and it's still the same so it must be a hardware issue.

When I get to the bottom of it I'll give your utils a good testing and report back, until then I can't say anything for sure.

The only other machine I have with ADFS is my Master and that doesn't like EEPROMs :roll:
cheers Wookie
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby daveejhitchins » Sat Jan 30, 2016 7:59 pm

Wookie wrote:I've tried with my original AP2 rom and with DaveH new AP6 rom but it's just the same, I've tried your original utils from DFS that previously worked and it's still the same so it must be a hardware issue.
Howard: Although the detection of RAM, ROM, EEPROM and empty sockets has been an issue (with the AP6 ROM), due to the buffering on the Plus 1 and/or AP6, I think it should be working OK! If, as you suggest, you think it's a hardware issue (?) I always start with a good cleaning of: ULA socket, Electron expansion connector, Plus 1 expansion connector (and the Plus 3 connectors, if fitted), to at least eliminate them before further investigation. Of course there's always the Elk OS ROM, if in a socket!

Hope that helps - Dave H :D
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby CMcDougall » Sat Jan 30, 2016 8:10 pm

I can test that for you Martin .... :^o yeah right, all my AD FFS are still stuck to my shoes :wink: good for grip in this snow though :D
I never use the EEP32 utils, this must be due to having a read /write switch , or no open swram bank on an elk :?
Maybe should put the page up to &1F00, for silly people with AD FFS & DFS 8)
ImageImageImage

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Wookie » Sat Jan 30, 2016 8:45 pm

CMcDougall wrote:Maybe should put the page up to &1F00, for silly people with AD FFS & DFS 8)

No need, due to my AP3+4 having a ram chip that DFS uses.

I never found page at 1D00 a problem on my Elk, but then I have a Slogger MRB so I have 28k free in all screen modes 8)

I find DFS much more limiting with it's 31 item catalogue (okay watford had 62) and reduced capacity compared to ADFS, with ADFS you get 640k on each disc, filled the directory with files ? just create another directory and stuff 'em in there. Imagine a modern multi-Terabyte hard drive and all we had was DFS and it's 31 file limit :lol:

p.s. Does anyone have an address for Acorn ? I wonder if it's still under warranty :D
cheers Wookie
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Sat Jan 30, 2016 9:13 pm

Oh dear Wookie, that's rubbish about your hardware issues :(

No worries though, it'll do when you get sorted, and anyway, like a speeding bullet, Col has stepped into the fray....

Cheers Col, it would be good if you could give that V3 EELOAD a quick spin under ADFS at some point but there's really no rush 8) . To be fair, the EEPxx utils aren't essential because you can simply overwrite an E2 device just like you can normal SWRAM (although with eeprom you need to employ a programming algorithm) so you don't have to erase first but it sometimes helps to be able to just clear the contents of an eeprom. The other options, <LOCK> / <UNLOCK> / <OFF> / <SUM> are again useful configuration tools but are not essential for loading the eeprom.

So, if you could when you get time at least try a couple of loads from disc and see if it all looks ok and gives the correct post-load sumcheck then that'd be helpful.

Note that it's just occurred to me whilst writing this that the load from ram option, *EELOAD @ <id> won't work as things stand because having relocated EELOAD to run at $1D00, it will, on initial loading, overwrite part of any image in the (current) ram buffer at $2000 before it does some runtime code moving to allow everything to operate below $2000. I need to think about this a little.... :roll: :-k :wink:

Edit 1 : Having thought about the ADFS high PAGE issue, I can of course load lower than $1D00 in the same way that I can load lower than $1900 with DFS. The latter can safely be pushed to $1100 and for ADFS, I think $1600 or even $1400 springs to mind. I'll have a play but it's quite possible that this will remove all my pain and make the ADFS compatibility job much easier.... :D

Edit 2 : Booo, no you can't... :(

Yes Colin, ADFS is indeed a game played with two dice :x

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Wookie » Sat Feb 13, 2016 11:55 pm

MartinB wrote:Oh dear Wookie, that's rubbish about your hardware issues :(

No worries though, it'll do when you get sorted, and anyway, like a speeding bullet, Col has stepped into the fray....

Cheers Col, it would be good if you could give that V3 EELOAD a quick spin under ADFS at some point but there's really no rush 8) . To be fair, the EEPxx utils aren't essential because you can simply overwrite an E2 device just like you can normal SWRAM (although with eeprom you need to employ a programming algorithm) so you don't have to erase first but it sometimes helps to be able to just clear the contents of an eeprom. The other options, <LOCK> / <UNLOCK> / <OFF> / <SUM> are again useful configuration tools but are not essential for loading the eeprom.

It lives again.....

Right MartinB I've tried your ADFS version of EELOAD and I haven't had a single failure with it \:D/

I/we could however do with a copy of EEP16/32 that runs above 1D00 so I can lock/unlock etc from ADFS if that is not too much trouble, as a work around I currently *DISC and run your original *EEP16/32 command from a DFS disc (corrupting ADFS's workspace in the process) then *ADFS and use the ADFS-friendly version of *EELOAD after swapping back to a ADFS disc.

But the main thing is it works ... yeehar!
cheers Wookie
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby 1024MAK » Sun Feb 14, 2016 12:53 am

Wookie wrote:It lives again.....
:D
Wookie wrote:But the main thing is it works ... yeehar!
=D>

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Sun Feb 14, 2016 8:57 am

Many thanks for that Howard... 8)

Wookie wrote:I/we could however do with a copy of EEP16/32 that runs above 1D00...

No worries, I fully intended to build those too - I'm juggling a few projects at the moment so I thought I might as well wait until you'd had a look at EELOAD (so I don't have to wrestle with ADFS myself :x) before I knock out the other utils. I mentioned when I posted this that there's an Elk issue regarding the '@' (program from memory) option due to the simple lack of memory in an Electron without Mode 7 so I might just remove that switch if an Elk is detected. I could recover some screen memory or something but to be fair, it's probably not worth the investment. The utils in an Elk will do absolutely everything else of course, it'll just mean that the @ loading switch (which probably only I use) is only available on a Beeb or Master.

So, I'll sort the other programs and tidy everything up this week all being well..... :wink:

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Wookie » Sun Feb 14, 2016 9:59 am

MartinB wrote:No worries, I fully intended to build those too - I'm juggling a few projects at the moment so I thought I might as well wait until you'd had a look at EELOAD (so I don't have to wrestle with ADFS myself :x) before I knock out the other utils. I mentioned when I posted this that there's an Elk issue regarding the '@' (program from memory) option due to the simple lack of memory in an Electron without Mode 7 so I might just remove that switch if an Elk is detected. I could recover some screen memory or something but to be fair, it's probably not worth the investment. The utils in an Elk will do absolutely everything else of course, it'll just mean that the @ loading switch (which probably only I use) is only available on a Beeb or Master.

So, I'll sort the other programs and tidy everything up this week all being well..... :wink:

No rush at all, I can do what I want with EEPROM's either using your original DFS version or by doing my ADFS/DFS disc swop. I have enough projects of my own that I'm neglecting to keep me busy.

If you want to remove the "@" option due to lack of available memory space that's fine with me, I never use it anyway.
cheers Wookie
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Mekon » Sun Feb 14, 2016 5:20 pm

Hi guys, I'm a long-time lurker and occasional poster - here's one of my occasional posts :)

This looks like it could be a rather useful addition to my machines. I've read through the thread a couple of times, but I'm not sure how to go about it. I've got a cassette based Electron with a Plus 1 and a somewhat poorly BBC micro with a temperamental DFS drive to play around with.

Is this the procedure?

1) Source an AT28C256 - From daveejhitchins?
2) Wire up according to MartinB's diagram (download/file.php?id=10115&mode=view)
2) Download MartinB's utilities from download/file.php?id=13270
3) Transfer utils and ROM images to disc (or tape?)

I've no idea how I would connect it up to an Electron - but otherwise, is that all I need to do?

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby daveejhitchins » Sun Feb 14, 2016 6:14 pm

Mekon wrote:1) Source an AT28C256 - From daveejhitchins?
2) Wire up according to MartinB's diagram (download/file.php?id=10115&mode=view)
2) Download MartinB's utilities from download/file.php?id=13270
3) Transfer utils and ROM images to disc (or tape?)

I've no idea how I would connect it up to an Electron - but otherwise, is that all I need to do?

#1 - No problem.
#2 - Works well.
#3 - Check with Martin re loading from Tape. I'm sure someone has done this or tried it?

AP6, You could have 2 x EEPROMs in there :D

I'm currently trying EEPROM in the ABR too. Results later . . . There may be other Cartridges that can support EEPROM?

Dave H :D
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Sun Feb 14, 2016 8:01 pm

Dave wrote:#3 - Check with Martin re loading from Tape. I'm sure someone has done this or tried it?

I'm sure someone has recently done this.... :-k. I can't think why it wouldn't work though - might be best to minimise tape juggling by loading the required image into the buffer at $2000 first ( *LOAD <filename> 2000 ) and then using the EELOAD option to program the eeprom direct from memory with *RUN EELOAD @

and wrote:There may be other Cartridges that can support EEPROM?

Indeed there are - I showed how to modify a standard Elk Plus 1 cart here ... O:) :-D

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Sun Feb 14, 2016 9:18 pm

Regarding running the E2 utilities from tape, my memory is clearly more volatile than yer average eeprom..... :roll: #-o

MartinB wrote:
Dave wrote:#3 - Check with Martin re loading from Tape. I'm sure someone has done this or tried it?

I'm sure someone has recently done this.... :-k. I can't think why it wouldn't work though...

So yes, the eeprom utils can be used from tape with a little tweaking - read the posts from here to the bottom of the page for skinnymathew's success story.... :wink:

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Mekon » Mon Feb 15, 2016 2:06 pm

Well that looks very promising. I'm planning on using the EEPROM for the same purpose as skinnymathew, so his MP3 files should come in very handy. :)

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Sun Feb 21, 2016 12:53 am

I've rebuilt all the eeprom configuration and programming utilities now to make them compatible with any DFS and the worst-case ADFS where PAGE=$1D00 (ffs :roll:) and I've also embodied a few minor tidying tweaks here and there. The only significant difference is that the EELOAD '@' switch now programs the specified eeprom from $3000-$6FFF rather than from the previous $2000. This will be fine for a MODE 7 Beeb but will impinge on screen memory in an Elk - I think the very few folk that might wants this to use option on an Elk will be sufficiently smart to manage the screen issue so I'm not going to bust a gut and over-complicate the utility.

The versions now are EELOAD V3.1A, EEP32 V3.0A and EEP16 V3.0A

@Wookie - I'd appreciate a spot of testing if you can find some time but no rush 8)

In the attached zip there's an ssd and an adf, each with all three utils and a couple of test images....

EDIT : See further down for download of later versions, minor fix embodied to correct Electron hang after 'Syntax Error'

A usage reminder for anyone unfamiliar....

*EELOAD <(filename) (@)> <id>

*EEP16 <(LOCK)(UNLOCK)(ERASE)(SUM)(OFF)> <id>

*EEP32 <(LOCK)(UNLOCK)(ERASE)(SUM)(OFF)> <idL><idH>

The EEP16 and EEP32 utils apply to a 16k single-rom configuration (eeprom A14 and A12 shorted) and a 32k dual-rom configuration respectively, EELOAD is used with both configurations.

Note that EELOAD and the EEPxx SUM and OFF commands can also be used with standard sideways ram, not just with eeprom.
Last edited by MartinB on Sun Feb 21, 2016 8:07 pm, edited 1 time in total.

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Wookie » Sun Feb 21, 2016 1:12 pm

MartinB wrote:I've rebuilt all the eeprom configuration and programming utilities now to make them compatible with any DFS and the worst-case ADFS where PAGE=$1D00 (ffs :roll:) and I've also embodied a few minor tidying tweaks here and there. The only significant difference is that the EELOAD '@' switch now programs the specified eeprom from $3000-$6FFF rather than from the previous $2000. This will be fine for a MODE 7 Beeb but will impinge on screen memory in an Elk - I think the very few folk that might wants this to use option on an Elk will be sufficiently smart to manage the screen issue so I'm not going to bust a gut and over-complicate the utility.

The versions now are EELOAD V3.1A, EEP32 V3.0A and EEP16 V3.0A

@Wookie - I'd appreciate a spot of testing if you can find some time but no rush 8)

Yeah they work just fine Image

I've tried using all 3 commands in all 3 modes of my Slogger MRB and tested both direct loading and using the "@" option. Everything works as it should!

Since you have to be careful not to corrupt/scroll the screen when using the "@" option if your not in MODE 7 or using shadow memory for the screen, my only suggestion is to loose all the blank lines that your printing to help avoid scrolling the screen, but that isn't important to me as I always use the direct loading option and I'm normally in 64K/Shadow ram mode anyway.

I find your checksum at the end of loading really handy, that way you can tell if the image has been corrupted whilst loading into EEPROM, I accidently scrolled the screen once and the checksum changed so I knew I had a duff image loaded.
cheers Wookie
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby tricky » Sun Feb 21, 2016 1:46 pm

You'll could use a20k mode and set a text window to a small area near the bottom of the screen (can't remember the VDU sequence, but I do use it in the carnival loading screen).

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Wookie » Sun Feb 21, 2016 1:53 pm

tricky wrote:You'll could use a20k mode and set a text window to a small area near the bottom of the screen (can't remember the VDU sequence, but I do use it in the carnival loading screen).

VDU 28,left x,bottom y,right x,top y

Just remember text origin 0,0 is top left, not bottom left as is the graphics origin :roll:
cheers Wookie
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Sun Feb 21, 2016 3:27 pm

Just to be clear for anyone reading, this only affects the @ option and is not part of the mainstream functionality. I did consider using display windows but decided it really isn't worth the effort. On Beebs, stick to Mode 7 for programming and on an Elk, don't use the @ option... :wink:

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Sun Feb 21, 2016 8:28 pm

Wookie has discovered a minor issue affecting use of the programs on an Electron only in that all three utilities will hang requiring a <Break> if a command line error is determined and 'Syntax Error' is reported. The hang occurs because I mistakenly located the host machine type detect after the command line is parsed so if a syntax error is detected and reported, the program aborts and returns to the prompt using the incorrect ROMSEL register address because the latter defaults to a Beeb prior to the correct host being determined. It seems this error has been present since I released the universal machine-independent suite of utilities back in October 2014! :shock:

(I do use the utils on a regular basis but apparently I don't make command line errors, at least not on an ElK.... :lol: )

Anyway, it's an easy fix and I've updated all three utilities which are attached below.

The versions now are EELOAD V3.2A, EEP32 V3.1A and EEP16 V3.1A dated 210216 - note that if you want to find the version number of any of my utilities, just type the command with no parameters. e.g. *EELOAD<Return>

EDIT : See further down thread for latest downloads.
Last edited by MartinB on Mon Aug 29, 2016 7:13 am, edited 1 time in total.

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby DutchAcorn » Fri Mar 11, 2016 7:40 pm

SteveF wrote:...but on ebay you can get 5 for £4.41 (http://www.ebay.co.uk/itm/5PCS-EEPROM-I ... SwpDdVUzUE). Is this too good to be true? ...

I got these from eBay a few weeks ago and put one in a model B following the diagram earlier in this thread (32K / dual rom option). Works fine! =D> :D
Paul

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Fri Mar 11, 2016 10:11 pm

Thanks very much for the feedback Paul, appreciated 8)

Good to know those chips are sound, I could do with a few more myself so I'll fire off an order... :)

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby duikkie » Sat Mar 12, 2016 7:17 am

from china free p&p :), it is possible :)

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby Mekon » Thu Mar 24, 2016 2:25 pm

Hurrah - I'm up and running now! Thanks to Dave H for supplying the EEPROMs, and to Martin B for achieving the Holy Grail and getting the whole thing working.

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby MartinB » Thu Mar 24, 2016 8:05 pm

Why thank-you sir! 8)

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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby SteveF » Tue Mar 29, 2016 12:29 am

I finally got round to building this for my BBC B; I went for the 32K approach with the extra flying lead because a) I'm greedy :-) b) this machine currently has no sideways RAM so having a free slot for something else as well as MMFS seemed desirable.

It is very cool to see it actually working - and once I got it going, that first load was doubly satisfying for the sheer speed! It's nice to feel I am one step further from being dependent on floppies. (I like having them, but I don't like having to rely on them.)

A few questions/observations from my perhaps unique-in-the-thread perspective as someone not too comfortable with a soldering iron:

- I used an intermediate flat-pin IC socket (as previously discussed) to avoid having to bend pins on the EEPROM. This worked, but for someone as hamfisted as me, soldering to the bent pins was still tricky. I bent them at exactly 90 degrees and didn't realise until I came to fit the thing just how closely spaced the ROM sockets are - the bent pins plus my big blobby solder connections were disturbingly close to contacting the adjacent ROMs. In hindsight I should probably have bent the pins more than 90 degrees. I sidestepped this issue by putting the EEPROM in the rightmost ROM socket (IC101), so I only had one bent pin (pin 1) adjacent to another ROM and that one happened not to be too chunkily soldered. :-)

- Am I right in thinking that you could avoid soldering to the bent pins at all by just snipping them off the intermediate IC socket and using test probes to connect to the pins on the EEPROM? You'd still have to solder to the switch and the test probes themselves, but even for me that bit wasn't particularly hard.

- I couldn't see any information/recommendation in the thread on which ROM socket to install the EEPROM in or which ROM banks it would appear as. Now having re-read this I see sydney's post on Mar 24 2014 covers this (although it superficially looks like it's relevant to a sideways RAM upgrade only). Anyway, it's probably far too big an ask, but I'll ask anyway: would it be possible to have a *EEPROBE command which probes all the ROM sockets and tells you "the EEPROM is in banks &X and &Y"?

- I got confused with the need to give the two ROM banks as an adjacent pair of hex digits at first; I can see this information is in the thread and once you know this it's easy, but it did trip me up. (Particularly because I was trying to "guess" which banks the EEPROM appeared in, so I was doing: *EELOAD FILE 0 - no, error says it's ROM. *EELOAD FILE 1 - no, error says it's ROM... *EELOAD FILE 9 - no, error says it's ROM. *EELOAD FILE 10 - syntax error. Hmm, does that mean it's bank 10 and the code is getting to a different place before failing?) Could we maybe get a brief README file added to the utils disc? I'd be happy to knock up a draft of this if it would help. [Edit: I am mixing things up here, of course. *EELOAD does fail with '10' but because it only expects a single hex digit not a decimal value. But still, I did get confused and a README would have probably sorted me out very easily. A longer syntax error message might be nice, but I am sure memory is tight and a README would be way more descriptive than even the longest syntax error. Actually, while I'm being really demanding, *EEPROBE could output "The EEPROM is in banks &X and &Y.\nTo load a ROM image, use *EELOAD filename X or *EELOAD filename Y.\nTo lock, use *EEP32 LOCK XY." etc. But the README would be way easier. :-)]

- I originally connected the 5V flying lead from the switch to pin 27 of the OS ROM. This meant that with the switch in the "write protect" position it seemed to function as a read-disable instead. I subsequently realised this was wrong as that's address bus line A14 not a fixed 5V. Completely my own fault, but I mention it in case anyone else sees that line of identical looking ROMs and thinks they're all the same. :-)

- I tend to move my Acorn machines around a fair bit due to lack of a proper home; what are the realistic risks if one or more of the flying leads are floating around loose when the machine is turned on? My gut feeling is this is pretty safe, as the test clips I'm using are spring loaded and I think the tip would safely retract if this happened, so they wouldn't short anything out at random.

- (I'm sure this is really really naive, please go easy on me!) Why is the 10K resistor needed on the connection to 5V? I'm looking at the BBC B circuit diagram and all sorts of pins just seem to be connected to 5V with no resistor at all. I *did* use one, but due to a quirk in how I ordered my parts I have 5 EEPROMS, 5 switches, 2 IC sockets and only one 10K resistor, so I'm wondering if I can get away without it if I want to build another one. I also find myself wondering if I could do away with the switch and just have a flying lead from EEPROM pin 27 which I connect to +5V in normal operation and to IC14 pin 1 when I want to reprogram; having to take the lid off to reprogram would be a minor hardship.

I hope this doesn't come across as negative; I've got it working now and as I say it's very cool indeed. :-)

Cheers.

Steve

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DutchAcorn
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Re: EEPROM - the Holy Grail of Sideways Rom?

Postby DutchAcorn » Tue Mar 29, 2016 5:44 am

Here's my implementation. The pins are bent out just enough to miss the socket. I have the flying leads under the PCB.
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