anybody used a Slogger Plus 2?

[Elk Towers]

Maybe the user guide is wrong and its left if you want to battery back ram and right if eproms as the pic of the populated board earlier had it to the right.

Nick

PS have ordered my own plus 2 board off of dave today

[aerworuld]

Maybe the user guide is wrong and its left if you want to battery back ram and right if eproms as the pic of the populated board earlier had it to the right.

agreed!

PS have ordered my own plus 2 board off of dave today

**IMPORTANT NOTE, 24/07/13** Later in this thread, at the bottom of this page, 1024MAK as put up a download link for his Plus 2 docs. I recommend using his component list, included in that zip, for absolute certainty of build success!


nice one!!! ok, here's my updated component list for the Plus 2, which so far seems to be working as it should:

ICs

74LS175
74LS20 (x2)
74LS04
74LS00 (x3)
74LS08
74LS260
74LS30
74LS139
74LS02
74LS133

Resistors

4.7k (x2)
20k

Diodes

1N4148 (x3)

Capacitors

100nF (x10)
10uF 16v (x2)

Misc

3 x Edge connectors, cut down to size from eBay
IC sockets
Pin headers


Please note I have not put in the components for the User Port element, as I did not do this bit myself as I use Martins EUP

I sourced the IC's mostly from ESR, but the rest I managed to find on eBay in good supply.

hope this helps!
Stuart

*edit* to keep things clearer for the folks who are looking only for the Plus 2, i'll start a new thread for the RS423 Plus 2 upgrade board.

[Elk Towers]

Another random thought - I wonder whether a Plus 1 case could be hacked to fit round a Plus 2?

This is possible but you will have approx 10mm of pcb sitting out the rear and anything fitted to the rear wont be able to be bolted together.


Nick

[Elk Towers]

Stuart.


Any chance you could post a nice clean and in focus overhead pic of you populated plus 2 please.

I am struggling to find where the diodes go, I know 2 go near the jumper top left but where does the third go.

Nick

[aerworuld]

Hi Nick,

I've got the three diodes in a line there by the jumper; I have no idea if that is correct I just tried it and it worked!

The way the board is laid out there seems to beg for three components but in the photo i was working from this part is obscured so i had to guess

I've no logic to back this beyond guesswork but my board is working so far....


Will try to produce a decent piccy at some point but at the moment i have wires all over the place from the RS423 board im fiddling about with.

Stuart

[Elk Towers]

Another question or two for you Stuart

Is the resistor above socket 15 the 20k one?

and which way round are the diodes?


Nick

[aerworuld]

Shopping then school run, will let you know when I get home!

[aerworuld]

ok, the resistor above socket 15 is indeed the 20k one, the three diodes by the jumper are all pointing to the right as you look down at the component side, that is to say the thick line on their body is to the right.

sorry for the poor terminology; this is not my area of expertise!

[Elk Towers]

Thanks Stuart

[Elk Towers]

another question for you Stuart

which way round are the two electrolytic caps?


Nick

[aerworuld]

Hi Nick, the caps on my board are thus:

Looking down at the component side as if plugged into the Elk the cap on the left is +ve to 49 (left most track) and -ve to the next one in 47

The cap on the right is +ve top -ve toward the Elk

Will try and put a pic up of the two

Stuart

[aerworuld]

Sorry its not a great shot, its the best I can get with my phone!

[Elk Towers]

Thanks Stuart

I am half to shoe-horning into a plus 1 case with the rear part of an elk attached on the back to bolt other i/fs on.

Nick

will some pics up later in the week as my work break keeps getting in the way

[aerworuld]

Aha I know what you mean!

The Plus 1 case is a good plan; if the RS423 upgrade eventually works I'll need to think about something like that to keep it all together

Good luck with it!

[1024MAK]

This will in turn indicate what supporting ICs might need to be present on the Plus 2 main board. I'm thinking of the problem of the empty sockets top right - are they needed or not?

I'm been thinking about those John; they are marked U3 and U4, whilst the user port 'option' is marked U1 and the RS423 board socket U2.

It might follow that these are the upgrade options so U3 and U4 are for the SWR?

Maybe U stands for "User option" or something like that?

U3 and U4 are next to the cartridge slots if I remember correctly, so maybe they do something related to them or relevant to SWR. A good clue would be to look at the PCB traces connected to them and see where they go - if they don't go anywhere near the RS423 part of the board then that suggests they probably don't affect it.

Looking at the boards I have (Thanks Dave!), that the RS432 board plugs into socket U2, if you look at the connections to the top 8 pins of U2 they all connect to the Databus. It also looks like the 4 rightmost pins on the bottom row go to address lines.

I've not yet traced either board, but it would certainly fit, and would also be out of the way of the other stuff on the Plus 2.

U3 and U4, look to me from the tracks like they might be LS chips of some sort, eg, LS00, LS02 etc.

Well, I've started reverse engineering the circuit of the Plus 2 board.

Because U3 & U4 were a total unknown, I started on this area of the board.
Are U3 & U4 needed for the serial RS423 option - no they are not needed.
Are U3 & U4 needed for the SWR option - no they are not needed.
The guess that they are 74 series logic chips is correct

The biggest clue was the inputs signals to U3 & U4 and the single output from U4.
This is part of an incomplete 16MHz to 1MHz clock generator circuit. It has a RESET input, 16MHz and PHI clock inputs and a single "1MHz" clock output. This output only goes to "pin" 10 on side A of the on board cartridge slots (as per the pin-out given in the Slogger instructions).

The circuit is similar to the circuit shown in figure 15.2a (page 227) of the electronic version of the EAUG. This circuit uses a 74LS74 and a 74LS163.
The version on the Plus 2 board does not however have any input connection to U3 pin 12 (74LS74 "D" input).

More when I can find some more time...

Mark

[aerworuld]

Wow, you've been busy Mark! Wish we had more documentation on this board to accompany it. Since we have a few of them jn circulation now it would be brilliant to see them realise their full potential

[Arcadian]

Have no idea whether these photos of my own Plus 2 will be of any use to anyone, but here they are anyway (note this board was originally supplied by Slogger i.e. it isn't a recent build).

[aerworuld]

Certainly filled a couple of gaps on my board!

*edit* i wonder, is that cable i can see the mod pencilled on to the Plus 2 docs posted by Hugh from Andrew Hilbig?

Stuart

[aerworuld]

There's a question which has stolen some sleep from me tonight: could i hang a second Plus 2 off the back of my existing one, or would these along with Plus 1 and everything plugged into them be too much for the Elk PSU?

I don't like keep unpluggling things and plugging in (interfaces, carts and all) and it would be nice to have the six cartridge slots this plan would give me...

i have a second board still and components left over from the first build....

Stuart

*edit* I've just been reading the Super Elk thread which seems to reassure that there is a fair bit of room for expansion?

[danielj]

There's a question which has stolen some sleep from me tonight: could i hang a second Plus 2 off the back of my existing one, or would these along with Plus 1 and everything plugged into them be too much for the Elk PSU?

I don't like keep unpluggling things and plugging in (interfaces, carts and all) and it would be nice to have the six cartridge slots this plan would give me...

i have a second board still and components left over from the first build....

Stuart

*edit* I've just been reading the Super Elk thread which seems to reassure that there is a fair bit of room for expansion?

It's not the PSU that's necessarily the issue here, it's the data and address lines from the processor and the mapping of the ROMs. The plus 2 isn't buffered, so sticking another one in there will mean that the address and data signals from the processor might not have enough "oomph" to speak to all the ICs that they need to (this is called "fan out") - usually you get around this by sticking a buffer in the path of the signals, which gives them another kick. Plus 2 doesn't have one of these (as far as I recall the plus 3 does actually buffer some of the signals) so you might find things getting flakey..

The other issues is the ROM mapping - if you're just connecting something to the slots like the joystick interface that doesn't have a paged ROM this won't matter, but most things you plug in do. The ROMs in the slots of the second Plus 2 will be mapped to the same numbers as the first so they'll just clash...

d.

d.

[aerworuld]

The point you make is a pretty fair one Daniel, i didn't think of that! I wont be needed to plug and unplug all that often, i just thought it would be nice

[richardtoohey]

Just get another Electron ... simple!

[aerworuld]

Just get another Electron ... simple!

haha, i like your thinking sir! i like the spiders-web approach to my old Elk though... she looks so proud, sat there in control of these wonderful gadgets

[1024MAK]

Okay, I have traced the section for the address decoder for the RS423 ACIA and VIA User port.
The diagram includes the pin-out for the 16 way DIL connector to the RS423 board.

Slogger Plus 2 RS423 and VIA User port address decoding cct - (s).png (132.46 KiB) Viewed 3721 times

Note that I have named the standard fitted chips IC1 onwards according to my own numbering scheme.

Mark

[aerworuld]

Because I already had Martins EUP i never bother populating the User Port section of my Plus 2 board. Could that be affecting the RS423 board then?

[1024MAK]

Because I already had Martins EUP i never bother populating the User Port section of my Plus 2 board. Could that be affecting the RS423 board then?

No, the user port just shares some of the same chips and circuits.
I see no reason why there should be any interaction between the RS423 serial port and the VIA used for the User Port.
As you did not fit the VIA, it cannot be the cause of any problems.

Mark

[sydney]

I finished soldering my plus 2 today and unfortunately it doesn't work. I just get a short pause followed by thick white/thin black horizontal lines.

I'm not sure what to do now. The soldering seems ok to my unskilled eye and is certainly no worse than the soldering on my pegasus and upurs cards. I have everything in the place shown in the photo on 8bs. However the photo posted by Arcadian seems to show a 74ls08 in the upper left corner where the 8bs photo seems to show a 74ls06.

I think I'll start by replacing as many of the chips I currently have spares of.

Simon

[aerworuld]

Sydney, i have a 74ls06 in the top left (as if board plugged into elk)

Stuart

[1024MAK]

Okay, I have made a lot of progress in reverse engineering / documenting the Slogger Plus 2

It is not complete, but here are the documents that I have put together so far. Please note that I have used my own component identification system.
Note that there are missing bits. This is due to Slogger not having connected all pins on all the chips or due to component values being yet to be fully determined beyond a guess.

Also the debate about the chip on the top left (which I call IC1), it is indeed a 74LS08 (which is a AND gate) NOT a 74LS06 (open collector inverter). If a 74LS06 has been fitted, replace it with a 74LS08 and you may also need to replace the 74LS139 as the output circuit on pin 10 may have been damaged.

I have increased the values of the electrolytic capacitors, as modern types are smaller and a little bit of extra capacitance to decouple the +5V power rail is a good thing. Both are available from Rapid.

Mark

[sydney]

Great work!
Mine has sat in a cupboard with most of my electron gear since April. I think I might have a couple of hours spare around lunchtime to check mine out.
Thank you!