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Perhaps I should have the control file loader bail, or at least warn the user if no cpu is defined.

Or maybe default to 6502 and also issue a warning, in case you where trying to process 6809 code.....

Cheers.

Phill.

Good way of spotting bridges, and checking for alignment of pins after tacking the corners is to hold the board up with a strong light behind it. makes it much easier to spot. But to echo the comments of others, that looks good for a first attempt. If you are worried about burning through too many x...

I really cannot understand what one does in one's bedroom has got to do with anyone except the people/things [sh*gging a BBC Model B, anyone?] taking part in whatever inwith the bedroom. Whilst I mostly agree with this..... Alan Turing should not have been pardoned: the act of pardoning presumes so...

How about £16 for a *SINGLE* Apple mac keycap.....plus £14 "shipping"

https://www.ebay.co.uk/itm/1984-Apple-M ... 4126966768

Cheers.

Phill.

I think I've found a bug in the 6809 core on the Godil. If you set a write to memory watch, it always lists the written data as $FF With the following watches set : >> blist 0: FF90 mask FFFF: Mem Wr Watch (trigger: Always) 1: FF92 mask FFFF: Mem Wr Watch (trigger: Always) 2: FF93 mask FFFF: Mem Wr ...

The thing that this makes me wonder..... Why on *EARTH* would you want to make something that's designed to be connected to a CPU interrupt line anything other than open drain / collector? Doesn't that rather defeat the ability to share an interrupt line between multiple sources, without additional ...

Pretty sure WinCUPL is free now. It still *appears* that they're going to charge you for a license but the download screen just gives you a license key you can use straight away. Though it is um full of 'features' I wish Atmel / Microchip would either fix it, update it or open source it so we can f...

I've used low profile ones for both the 4MHz and the 3.57MHz ones on a couple of my Atoms, I pretty much supply a low profile 4MHz with a RAMROM these days as even the reasonable sized normal crystal will foul with it.

Cheers.

Phill.

Hi all, Does anyone know where I can get a negative voltage generator module** needs to be able to generate approx 100-200mA at either -5V or -12V (not both at the same time) from an input of +5 or +12 respectively. **I want a reputable supplier, so am not interested in Aliexpress, Bangood etc. An e...

To be honest, the drive is probably toast. You may be able to get the head stuck back on the top assembly but you have a 99.9999% chance of it being out of correct alignment. Oh it might appear to read, write and format correctly but you'll probably not be able to use disks written in it (to the top...

hoglet wrote: ↑

Thu May 07, 2020 7:29 am

You need to switch to the dev branch before building. Either do a "git checkout dev" before you build, or use the -b dev option to clone)

Cheers Dave, that seems to have done it

Phill.

Ahh that would probably do the trick though doesn't seem to be in the version (of the 6809) I have loaded onto the godil, but that's 0.7x and I notice the current is 0.98....guess it's time to update :) Right just cloned the github, modified target\common\Makefile.inc to suit windows then went into...

The Lattice ispLEVER Classic says it costs but still seems to be free. I had to renew my licenses (1 year license had expired) and the direct link to get a free license still works... the 4256V dev boards are cheap. Right I'll download it and see if I can get a free license if just to evaluate. Hum...

Lattice still make plenty of 5V tolerant CPLDs and they were always similar or cheaper to the Xilinx equivalents. Mircochip (Atmel) still make 5V CPLDs. But both seem to charge for their development software licenses, or have buggy software, I'm looking at you Atmel WinCUPL! Was looking at evaluati...

I have just ordered two pieces @Farnell. On the Dutch website they are still cheap: https://nl.farnell.com/search?st=XC9572xl Yeah they where still reasonable on the UK farnell site too.... I refuse to buy Chinese CPLD's as it went wrong twice. One time I ordered XC9572XL and I got them but in the ...

I actually emailed Digikey about this, as DragonMMC, DragonDiag, and several of my Acorn related projects use them. This is the reply I got : "Thank you for your inquiry. I checked with our Cost Administrator and she said Xilinx substantially increased their price on this part on March 30, but they ...

Just spotted this : "Over 20 massive Gigabytes of Retro Fun" is that as opposed to "20 small gigabytes" LOL

Cheers.

Phill.

I was at one point compiling an Excel sheet of PC motherboards that would read/write/format single density floppy disks. It's interesting to note that there seemed to be some that would read and write but not format which was odd, but you could of course get round that by formatting on the beeb firs...

Something similar already exists - the command is called "next": https://github.com/hoglet67/AtomBusMon/wiki/User-Manual---Command-Reference#next-n It can be used to skip over subroutines or out of some loops. It would be very easy to extend it to take an optional address, and use that instead of t...

I have a feature request.....

A go command that you specify an address to and it goes until that address. Essentially an on the fly breakpoint usefull where you want to skip
say a subroutine, but don't want to go through all the hassle of manually setting a breakpoint.

Cheers.

Phill.

I find Beebdis incredibly useful, Glad to hear that, I recently used it to disassemble Dragondos 2.f, so I've been tinkering with it recently. I thought I pushed the latest to github, I'll check tomorrow. I discovered what looks to be a bug with versions 1.20 and 1.25 - the "stringscan" function do...

Hi all,

Is there a current recommended FPGA board as last time I looked I couldn't find the epizza board for sale anymore?

Cheers.

Phill.

Couple of things to bear in mind if you are using the WD65C02.... You correctly seem to have a jumper on Pin 1, as this is GND on a normal 6502, but an output on the WD. Do you have pullups on IRQ, NMI and BE ? Also this note from the datasheet RE: PHI2 : "Phase 2 In (PHI2) is the system clock input...

got a Panasonic CF18 toughbook with now a blank working 60GB hard disc in caddy. Obviously has no floppy or CD player, so the Q is, how do I do it :? Surely can't just shove in a USB stick into the port as no drivers will be installed to see it. Depends on the laptop, most modern ones will boot fro...

Asking for a friend**,

What is that cheapish EPROM / Flash programmer that some of you use, or can you recomend one please. Ideally needs to be able to program the 39SF010A flash roms I tend to use....

**I personally have an expensiveish Wellon VP590.

Cheers.

Phill.

I have to say I find this part of the schematic very confusing. Screenshot 2020-04-15 at 5.48.43 pm.png If you (or anyone else with a BBC card) could buzz out the connections, I would very much appreciate it. Isn't that just a clocked R-S flipflop, CTRL and SHIFT are select the state of the FF, hit...

I'm guessing (from personal experience when I was at college in the late 80s**), that Pascal at least may have been used in some schools / colleges to teach programming, so while it possibly didn't yeild any commercial software, it would have been used for more than 'hello world' :) **We used Turbo ...

My Casio FX-82 pretty much got me through my O and A levels. Only thing it doesn't have is base conversion which is a shame.

Cheers.

Phill.

Did you cut the tracks as directed in the upgrade guide, if so have you put those back?

Cheers.

Phill.

I've attempted the standard upgrade detailed here as I have 8 64bit ram chips http://archive.worldofdragon.org/index.php?title=Dragon_32_-_64K_Upgrade but I'm getting this screen. Anyone got any ideas what might be wrong. Tried with ic33 pin 8 GND connected and not connected. Seems strange that the...