MGH8060GAL SC/MP microcomputer - support thread

[avrkris]

Hey Guys,

A lot of people here enjoyed the MGH8060 project. Looks like most of the users ended up "modding" it to support the more flexible address decoding using GAL22V10 (or similar) ... I've decided to include this modification into a new project called MGH8060GAL...

The project is shared on PCBWay and will be maintained via GitHub.

https://github.com/Kris-Sekula/MGH8060GAL

[Phil__G]

This really is a superb little machine, it has everything - a configurable 64k map, three parallel ports, aux serial for the Aliexpress receipt printer, and my favourite, the DLY led
I've added a section to my SC/MP page with the build images and source, plus a doc describing the software build:
https://www.mccrash-racing.co.uk/phi...htm#mgh8060gal
This includes KB+, NIBL-E, PAGE3.SYS, NIBL-E Toolkit, NIBL-FP and an optional boot-menu (some like menus, some prefer not)

In a nutshell all you need from the zip is the JED file for the GAL and the ready-to-go image file for the eprom. The PCB is really nice, well laid out and not at all cramped.
All the SC/MP lines are brought out to "INSbus" in the unlikely event you'd ever need to expand this system!

Its great to see the humble little SC/MP chip going from strength to strength...

Cheers
Phil

[Phil__G]

Here's mine listing a simple NIBL program to the £15 Aliexpress receipt printer. The list routine is part of the NIBL-E Toolkit in ROM.

[ortek_service]

Originally Posted by avrkris

Hey Guys,

A lot of people here enjoyed the MGH8060 project. Looks like most of the users ended up "modding" it to support the more flexible address decoding using GAL22V10 (or similar) ... I've decided to include this modification into a new project called MGH8060GAL...

The project is shared on PCBWay and will be maintained via GitHub.

https://github.com/Kris-Sekula/MGH8060GAL

Welcome to the group, Kris.

And thanks for info on the on this new GAL version (which has appeared rather-sooner than expected as Phil had said around 3wks ago in details of mod-ing the original MGH8060 with the GAL16V8, that this new version was not imminent).

It looks like with the move to a larger DIL32 68128 (marked on board 3D picture) / (62828 marked on schematic) 128KB SRAM, then a DS1245Y (that's been used on the MK14-NV board by coolsnaz2 (Ian)), could also be used here to allow retention of programs.

I'm intrigued about the DLY LED, so I'm wondering what this does?


And I also thought it may be possible to add this D-FLG, latched from D6 (as well as H-FLG, latched from D7 - if that's also useful?) to the previous MGH8060 mod-ed with GAL16V8 version.

Unfortunately, the GAL16V8 on that doesn't have any more Output-capable pins free (being only a 20pin device rather than the 24pin GAL22V10 now being used here).
However, there are 4 unused GAL16V8 Input pins on that, that are free (once isolated from ground), and I think that if A11 (wire linked to pin12) to one of these inputs, then that would free-up an I/O pin to use as an output.
One of the A12 to A15 lines could also be moved, although that would involve a bit-more track-cutting and wire linking, to support H-FLG as well.
It will of course involve a few slight changes to the GAL equations, but doesn't look too difficult and I may give it a go.

I'm also thinking of making one of the serial headers on that, an Aux Serial one, for use with the receipt printer etc. It looks like this can be done by just cutting existing TX and RX_USB from pins 2 & 3, then re-patching SOUT & SIN to these.

Owen

[avrkris]

Hi Owen,

The MGH8060GAL was something I was thinking to implement for a while, but with my busy "day job" schedule, I decided to best approach would be to "underpromise" and "overdeliver" ...

The DLY LED is linked to the the latched output of D6 line (generated by the GAL22V10) ... it indicates "delay cycle is starting" - ie when you use delay instructin in the code.

The mods that you suggest for MGH8060 make sense, but I haven't tried, since I have the MGH8060GAL version of the pcb this functionality is "built in"

Kris

[Mark1960]

The delay flag could also be used as an extra output, maybe to disable rom and enable ram after ram has been setup. Similar to the way cpm boots from rom and sets up a 64k ram.

Halt flag can also be usefull. MK14 uses this for single step, it could also be connected to CONT input for a programmed halt as intended by Nat semi.

R/W or Instruction flag probably not so usefull unless you are implementing memory management and/or system/user modes.

[Phil__G]

Originally Posted by ortek_service

And I also thought it may be possible to add this D-FLG, latched from D6 (as well as H-FLG, latched from D7 - if that's also useful?) to the previous MGH8060 mod-ed with GAL16V8 version.

Originally Posted by avrkris

...make sense, but I haven't tried...

I have! On my original with the LS574 I extended all the data lines D0-D7 to the latch and brought them out to a header socket.
I love the DLY led, its really only blinkenlights but it does give you a clue whats happening, flashing during serial I/O etc:
Discussed here: https://www.vintage-radio.net/forum/...16#post1623616
DLY led is plugged into the extra header socket to the right of the FTDI

[ortek_service]

Thanks Kris / Mark / Phil for the info.

After some searching, I've now discovered this useful summary of all the 'Flags' (as well as how the upper address lines A12..A15) are available on the (shared-usage) 'Databus' when nADS is asserted: https://www.heinpragt-software.com/i...cmp-processor/
- Although they seemed to have got NMOS and PMOS the wrong way round, when describing the SC/MP-I/II power pins and don't show Gnd on pinout diagram so I assume that is PMOS version
BTW, I've just noticed the INS8060 power pins seem to be absent from the MGH8060(GAL) KiCAD schematics, so I assume there is some hidden mapping to global VCC & GND in the building of that particular part - Whereas other IC's do have power pins shown / a separate 'Power' block (but then have extra suffix letter on the part's reference designator ID) that is connected to VCC & GND.

The information on the D-Flag / H-Flag etc is no doubt also buried in some NS Info / appears to be in this quite extensive info (also with KiCAD SC/MP schematic, that does have power-pins shown on the symbol, so I assume used a different library / there's an option to show/hide these): http://www.moria.de/tech/scmp/cpuscmp/


I wonder if the R-Flag & I-Flag, put on D4 & D5 with nADS asserted, could also be used to drive even more 'blinkenlights'? - but maybe (even on an SC/MP) these would be changing too-fast to make those lines useful for that purpose (And even the larger GAL22V10 hasn't got any spare outputs to use to provide those, so would need an even larger one / a dedicated logic IC register / latch).

I did also notice that on this MGH8060GAL, A10 also goes into the GAL22V10 (rather than just A11) on the GAL16V8 added to the MGH8060(R) version.
So I assume that is to allow finer granularity of 1KB rerather than 2KB segments of the memory-map (Although A10 doesn't appear to be used yet in equations liatee on the schematic).

[avrkris]

Owen,

We ran out of outputs for more "blinekenlights" on the 22V10... but all other signals are on the INSBus, so one could put a dedicated latch (like the 74HC573 used on the non-GAL version of the PCB) on an "expansion" board and create all the flags as per the SC/MP documentation.

For the KiCad symbol that I created for the INS8060, I decided to "hide" the power lines, but those are of course connected on the PCB ... Don't remember the reason I took this approach, I'll change it next time I touch the schematic ... just for consistency.

you are "spot-on" regarding the A10 going to the 22V10 ...I had "spare" input pins on the 22V10, so I decided to run A10, just in case someone wants more granularity on address decoding.

Thanks
Kris

[Phil__G]

If anyone in the UK is interested in assembling an MGH8060GAL but isnt sure about the GAL, I dont mind doing a few pre-programmed GALs at cost, I buy genuine OEM chips (Atmel/Microchip) from RS, they are presently £2.17 each plus Royal Mail "large letter" postage, say £4 all in. Just PM your postal address please
Cheers
Phil

[ortek_service]

I'd forgot that Atmel (Now Microchip) ATF22V10's were a 'second'-source for (Discontinued 10years ago? by the Lattice originator) GAL22V10's as surprisingly they hadn't included 'GAL' in the part-number - National Semiconductor (Now TI) had originally on the other 'second' source. But it seems those are also discontinued as they now only list (Mil Spec Temperature range) PAL's: https://www.ti.com/logic-voltage-tra.../overview.html
(Although TI seem to be releasing an 8-GPIO's PLD new product, but in a very-small 1.6x1.6mm SM QFP package, so maybe more like 'GreenPAK' devices: https://www.ti.com/product/TPLD1201 )

And RS are selling these ATF22V10 ones (along with ATF16V8's) for a reasonably price (Although you do have to buy MOQ of 5off)


After recently getting 10off GAL16V8's for < £4 in total from 'LAKE' store on Aliexpress, that all worked OK, I've just got some original Lattice GAL22V10's (and also Lattice GAL18V10's - also obsolete but never seemed to have a second-source, to update the original MGH8060 version the most versatile I can without external parts to the board) from 'QIAOMAER' store on Aliexpress.

They were in lots of 5off, at £4 for 5off GAL22V10D-15LP's / £2.19 for 5off GAL 18V10B-20LP's), but there was £2.57 delivery fee on each type, so I did buy a couple of lots to spread the cost per device. Although they only took 10 days to arrive, despite post here having Easter holidays.
(I also ordered and received at the same time one of those receipt printers from 'China Intelligent Manufacturing Store' on there, to use with MGH8060 etc board)

And all seem to work OK, with the 10off GAL18V10's (all with the same batch-codes), being blank. Whereas the GAL22V10's (9off all with same '1309' date-code, despite only some have a pin1 indent dot in the package, and the other date-coded '1106') were all programmed with 3 different contents-checksum's between them, but erased then blank-checked OK.