Search found 3640 matches

by jgharston
Sun Sep 22, 2019 6:13 pm
Forum: programming
Topic: Control-N - page mode query
Replies: 8
Views: 147

Re: Control-N - page mode query

This is not my field but couldn't a temporary interrupt, commenced on printing text and ending on completion, check for page mode being activated and a shift being awaited, in which case a text window could pop up with the requisite message? It wouldn't be an interrupt, it would be hanging onto KEY...
by jgharston
Sun Sep 22, 2019 6:03 pm
Forum: programming
Topic: Control-N - page mode query
Replies: 8
Views: 147

Re: Control-N - page mode query

I'm also looking to detect when a Beeb has paused text scrolling, and then (hopefully - not working yet) insert a SHIFT into the keyboard scan to continue scrolling once I've diddled with MODE 7 screen memory a bit. It's a long story. You can't "insert a SHIFT into the keyboard scan". SHIFT (and CT...
by jgharston
Fri Sep 20, 2019 8:17 pm
Forum: software: other
Topic: Torch MCP Versions
Replies: 3
Views: 124

Re: Torch MCP Versions

Wot? Shift-dot for ! Shift-1 gives * ?!?!?!? The whole matrix seems very different, not even normal characters match so not able to type anything until I remap everything. The matrix is here , and it is well different. I can't see why they changed the matrix, go ahead and extra keys in the spare co...
by jgharston
Fri Sep 20, 2019 10:55 am
Forum: software: other
Topic: Torch MCP Versions
Replies: 3
Views: 124

Re: Torch MCP Versions

... Keyboard: B = BBC B I = Torch, the CIL variant has completely different keyboard when emulated. Interesting, all the ROMs I have are xBx versions that came from Torch machines based on a BBC+8271 with this keyboard: Torch keyboard layout ===================== +-----+-----+-----+-----+ +-----+--...
by jgharston
Wed Sep 18, 2019 3:58 pm
Forum: hardware
Topic: Casper 68000 Co-Pro
Replies: 21
Views: 3276

Re: Casper 68000 Co-Pro

Pernod wrote:
Wed Sep 18, 2019 12:28 pm
jgharston wrote:
Thu Dec 18, 2014 4:31 pm
I also have the schematics for the Atlas 68000 card. That used something called a AM2950 to talk to the BBC.
Did these ever get scanned?
I made a start: http://mdfs.net/Info/Comp/Torch/
The 68000 stuff is still humungous BMP files that need stitching together.
by jgharston
Tue Sep 17, 2019 11:20 pm
Forum: programming
Topic: Hardware sideways scrolling in Beeb BASIC using VDU command?
Replies: 3
Views: 200

Re: Hardware sideways scrolling in Beeb BASIC using VDU command?

CRTC registers 12 and 13 set the address DIV 8 of the start of the displayed screen. Try this in various MODEs: 10 MODE 0 20 *HELP 30 addr%=HIMEM 40 REPEAT 45 PRINTTAB(0,1);~addr%; 50 VDU 23;12,(addr%/8) DIV 256;0;0;0 60 VDU 23;13,(addr%/8) AND 255;0;0;0 70 A%=INKEY(100) 80 addr%=addr%+8 90 UNTIL FA...
by jgharston
Tue Sep 17, 2019 7:40 pm
Forum: general
Topic: TOC for 40 Best Machine Code Routines
Replies: 6
Views: 199

Re: TOC for 40 Best Machine Code Routines

Not great but just about readable Some notes: The Break Intercept Code doesn't need to save any registers, as nothing is passed to it (other than Carry) and nothing is returned from it, so all those PHP:PHA:TXA:PHA etc can be got rid of. It's not a permanent *KEY10, it's stuffing keypresses into th...
by jgharston
Tue Sep 17, 2019 7:28 pm
Forum: programming
Topic: Control-N - page mode query
Replies: 8
Views: 147

Re: Control-N - page mode query

I wonder if anyone can help with this query. I'm writing my text adventure game and for locations where there's a lot of text and potentially objects also dropped in the location I'm going to insert a VDU14 (Control N) before printing text and then VDU15 (Control O) afterwards to resume. To the uni...
by jgharston
Tue Sep 17, 2019 10:40 am
Forum: general
Topic: TOC for 40 Best Machine Code Routines
Replies: 6
Views: 199

Re: TOC for 40 Best Machine Code Routines

Program 13 "Permanant [Function] Key 10" sounds interesting.... It's something I've needed on occasion Something like: Point Break Intercept Vector to some code. Code does: BCC skip ; only do once LDA osbyteFD:BEQ skip ; not hard break LDX #key AND 255:LDY #key DIV 256:JMP oscli .skip RTS .key EQUS...
by jgharston
Tue Sep 17, 2019 10:36 am
Forum: for sale / freebies
Topic: VideoNuLA boards
Replies: 96
Views: 15300

Re: VideoNuLA boards

*To save one byte OSBYTE 19 falls through into OSBYTE 160, so once a Sync has happened, there's LDY &0301,X:LDA &0300,X:TAX:RTS:ROR A:PLP:ROL A:PLA:CLV:RTS before you get back to the caller, 36 cycles if I've counted right. Plus any interrupts? Interupts are disabled until the PLP, so LDY &0301,X:L...
by jgharston
Mon Sep 16, 2019 11:16 pm
Forum: for sale / freebies
Topic: VideoNuLA boards
Replies: 96
Views: 15300

Re: VideoNuLA boards

It's turned out to be not such a problem in the end I just reset every frame and put up with the occasional glitch - I must track down where these rogue vsyncs are coming from! In the updated *LDPIC that's what I did, wait for VSync (OSBYTE 19) then do a nULA reset. Very occasionally I would notice...
by jgharston
Mon Sep 16, 2019 11:03 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 32
Views: 1356

Re: Looking for inspiration - debugging E2P

Maybe something like: .Hostcmd12 CMP #$0C BNE Hostcmd15 \ If not command 12 move on to 15 TYA PHA TXA PHA LDA JumpIntoCode+2-E2PClientCode+$F800 PHA LDA JumpIntoCode+1-E2PClientCode+$F800 PHA JSR EnterCode PLA LDA JumpIntoCode+1-E2PClientCode+$F800 PLA LDA JumpIntoCode+2-E2PClientCode+$F800 PLA TAX ...
by jgharston
Mon Sep 16, 2019 10:57 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 32
Views: 1356

Re: Looking for inspiration - debugging E2P

This code: .ParasiteOSBYTE CMP #$82 BCC L2D59 CMP #$84 BEQ L2D52 BCS L2D59 TAX LDY LF963-E2PClientCode+$F800,X \ Exact meaning is unclear? LDX #$00 .NullCall \ Was F9E4 RTS BRK .L2D51 EQUB $08 .L2D52 LDX JumpIntoCode-E2PClientCode+$F800+1 LDY JumpIntoCode-E2PClientCode+$F800+2 RTS Is: .ParasiteOSBYT...
by jgharston
Mon Sep 16, 2019 10:49 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 32
Views: 1356

Re: Looking for inspiration - debugging E2P

The data transfer appeats to be at .CommandPollLoop: .CommandPollLoop LDA #$00 STA Parasite_RegIOto2P .HighSpeedLoop JSR NMItemp-MemWindowStart+$FF00 \ Process command BNE HostCmd8912 BEQ HighSpeedLoop This eventually gets to HostCmd12, and this is where the context is lost with ths LDX #&FF:TXS: \ ...
by jgharston
Mon Sep 16, 2019 10:30 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 32
Views: 1356

Re: Looking for inspiration - debugging E2P

Going through the E2P code, the equivalent of OSCLI_IO is PassCommandToHost: .PassUnknownCmdToHost LDX $F0 LDY $F1 LDA #LO(HostOSCLI-L0400+$0400) STA Parasite_Reg2POScalltoIO JSR SendStarCommandToHost-E2PClientCode+$F800 JMP WaitForHost-E2PClientCode+$F800 So the WaitForHost is the equivalent of the...
by jgharston
Mon Sep 16, 2019 10:23 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 32
Views: 1356

Re: Looking for inspiration - debugging E2P

Using your description of what happens I'll trace through the Acorn code to see if I can follow it, then I'll try to find the equivalent stages in the John Wike version. It's a bit fiddly as there's a double-lookup to get the transfer address. The foreground is waiting for an Acknowledge, the backg...
by jgharston
Mon Sep 16, 2019 6:53 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 32
Views: 1356

Re: Looking for inspiration - debugging E2P

One thing I can't figure out about the Acorn method is how it transfers the execution address over the tube. I can see how it transfers the data itself, but I can't work out how the client processor receives the execution address. I notice that all three of the addresses PROG, MEMTOP and TRANS all ...
by jgharston
Sun Sep 15, 2019 2:35 pm
Forum: upcoming and recent events & exhibitions
Topic: Acorn World and ABUG meetup, Cambridge 20-22nd September 2019.
Replies: 235
Views: 7716

Re: Acorn World and ABUG meetup, Cambridge 20-22nd September 2019. FULL

Looking at my schedule and finances, I'm going to have to pull out of next weekend, so that's a full-kitter table available. (Annoying as I wanted to do some testing of my networking code with the FileStore.)

I hope to get to the Farnborough November meet-up.
by jgharston
Sat Sep 14, 2019 11:33 pm
Forum: software: other
Topic: Arabic
Replies: 4
Views: 222

Re: Arabic

Ah, so you're Edinburgh Software Products . The internationalisation on input works by having another service call , which is called if the keyboard translation OSBYTEs point into low memory. I happened to be typing it up just a couple of days ago as an offshoot from working on the keyboard code for...
by jgharston
Sat Sep 14, 2019 9:40 am
Forum: hardware
Topic: Epson SD-521 DD errors/fail
Replies: 32
Views: 309

Re: Epson SD-521 DD errors/fail

Colday wrote:
Sat Sep 14, 2019 9:04 am

Code: Select all

BBC Computer 32K
Acorn ADFS   <-------
BASIC
>*ENABLE
No directory
>
So, I have removed the ROMs from the boards, and the screenshot is what I get
It would help if you selected DISK before issuing DISK commands.
by jgharston
Sat Sep 14, 2019 1:15 am
Forum: hardware
Topic: connected BBC B to Internet no Hardware Modem
Replies: 7
Views: 324

Re: connected BBC B to Internet success

Is there any comms software on disc or rom that has a viewdatat mode Run in MODE 7: REM > SimpleTerm REM Simplest possible BBC serial terminal program : ON ERROR OSCLI "FX2":OSCLI "FX3":REPORT:PRINT:END *FX229,1 *FX2,2 REPEAT IF ADVAL(-1):OSCLI "FX3,3":VDU GET:*FX3 IF ADVAL(-2):OSCLI "FX2,1":VDU GE...
by jgharston
Fri Sep 13, 2019 10:50 am
Forum: emulators
Topic: b-em PDP11 tube processor
Replies: 7
Views: 233

Re: b-em PDP11 tube processor

If the host crashes the parasite by overwriting the workspace of the code that is receiving the transfer then the tranfer will fail just as surely as if the parasite had chosen to ignore the incoming data with the additional anoyance of crashing the parasite so having the client ROM check the incom...
by jgharston
Fri Sep 13, 2019 10:43 am
Forum: emulators
Topic: b-em PDP11 tube processor
Replies: 7
Views: 233

Re: b-em PDP11 tube processor

3. The PDP11 client ROM fails to defend against it's own data areas being overwritten by incoming data from the tube. This means it crashes with MOS 3.50 because this transfers a (useless to the PDP11) version of BASIC across that is being relocated to run in high memory (on the 6502) and therefore...
by jgharston
Fri Sep 13, 2019 10:28 am
Forum: for sale / freebies
Topic: More attic finds . . . Updated :o)
Replies: 31
Views: 1013

Re: More attic finds . . .

Wheel_nut wrote:
Wed Sep 11, 2019 2:36 pm
Perfect for a Car Battery Charger. !0V ac rectified - 10 x 1.414 = 14.14V dc. That should charge a Car Battery in a couple of hours. :D
Surely it's x 1/root(2) not x root(2), it has to be less than the peak as you're filling in the troughs by chopping off the peaks. So 10VAC = 7V DC.
by jgharston
Thu Sep 12, 2019 4:15 pm
Forum: software
Topic: Lost RISC OS Econet, AUN and NFS software
Replies: 16
Views: 1861

Re: Lost RISC OS Econet, AUN and NFS software

cmj6502 wrote:
Thu Sep 12, 2019 3:58 pm
Also "Advanced Level 4" .. I am not sure what was advanced about it compared to the normal one.
I think.... it implements support for files with 32-bit lengths, that is longer than 16M.
by jgharston
Sat Sep 07, 2019 9:24 am
Forum: emulators
Topic: b-em - bug or misunderstanding
Replies: 12
Views: 644

Re: b-em - bug or misunderstanding

pau1ie wrote:
Fri Sep 06, 2019 9:27 pm
Panos doesn't seem to work on a model B - It needs a master 128, but maybe this is just the version included.
I've had PanOS working on an Electron, so it should work on a BBC.
by jgharston
Sat Sep 07, 2019 9:22 am
Forum: programming
Topic: Determining Graphics Modes
Replies: 6
Views: 299

Re: Determining Graphics Modes

BCP (rather boringly) is not making any direct writes to screen memory, so it does not need to know if or not shadow memory is in use. I just need to know how many colours are available. That's a different question. If you want to know how many colours are available, the question is "how many colou...
by jgharston
Sat Sep 07, 2019 9:17 am
Forum: programming
Topic: Determining Graphics Modes
Replies: 6
Views: 299

Re: Determining Graphics Modes

BeebWiki has a similar suggestion: http://beebwiki.mdfs.net/Reading_screen_mode - though it uses osbyte $87 to read the mode. That's an option, but I figure you might as well just read the VDU variables, It's not an option, it's *THE* *SPECIFIED* API. Use OSBYTE &87, as that is the defined API to a...
by jgharston
Fri Sep 06, 2019 8:44 am
Forum: other vintage computer hardware, software and games
Topic: 27C400/800/160/320 emulator/ROM switcher
Replies: 17
Views: 516

Re: 27C400/800/160/320 emulator/ROM switcher

cmorley wrote:
Sun Aug 18, 2019 2:49 pm
Master MOS adapter:Photo0731.jpg
Won't fit with a GoMMC as it overlaps the next socket. :(