Search found 101 matches

by JonB
06 Oct 2017 09:11
Forum: MEMOFEST 2017
Topic: What to DO at Memofest 2017
Replies: 17
Views: 4852

Re: What to DO at Memofest 2017

Martin, I have gazillions of disks for the Tattie. Including Elite (which is copy protected, unfortunately). Most of them contain productivity software, but I have some games too. I also have a prototype SD card device that emulates a FDD, fits to the 50 way expansion port and has a ROM. It was made...
by JonB
05 Oct 2017 10:29
Forum: TRADING AND COLLECTING
Topic: Wanted: Faulty DRAM chips wanted!
Replies: 6
Views: 2813

Re: Wanted: Faulty DRAM chips wanted!

I have a bag of the buggers. Suspect 4116s that is. I could bring 'em to the 'fest next week if you like. However.. not sure if they really are toast or not - you know how impulsive I am with swapping out chips unnecessarily.. So if you find any good 'uns, I could use 'em back.. :P
by JonB
02 Oct 2017 10:23
Forum: TRADING AND COLLECTING
Topic: Wanted: Faulty DRAM chips wanted!
Replies: 6
Views: 2813

Re: Wanted: Faulty DRAM chips wanted!

Mark, are you planning on building a DRAM tester? That'd be pretty cool!
by JonB
02 Oct 2017 10:17
Forum: MEMOFEST 2017
Topic: What to DO at Memofest 2017
Replies: 17
Views: 4852

Re: What to DO at Memofest 2017

As Memofest is in Hastings (reasonably nearby) I think attendance might be on the cards (pending permission from the Boss!).. I'd like to bring something, but what? As I haven't really done anything with it of note with my MTX, maybe I could bring something else of interest? Some suggestions: A TRS-...
by JonB
19 Oct 2016 21:38
Forum: CP/M
Topic: Help request: Patching a CF card driver in CP/M 2.2
Replies: 4
Views: 2157

Re: Help request: Patching a CF card driver in CP/M 2.2

Thanks Martin

What I'm after is a bit of general CP/M 2.2 disk driver writing advice. I think I have done it right according to the CPM Alteration Guide, but as I said it ain't working. I wonder how you debug the BDOS..?
by JonB
19 Oct 2016 16:35
Forum: CP/M
Topic: Help request: Patching a CF card driver in CP/M 2.2
Replies: 4
Views: 2157

Help request: Patching a CF card driver in CP/M 2.2

One for the CP/M hard core guys... and apologies if you read the same question elsewhere! I'm writing a CF adapter driver for a vanilla CP/M 2.2 implementation. The read and write routines are already written and working on a different CP/M device. They use a non standard interface because they're p...
by JonB
08 May 2016 11:11
Forum: OFF TOPIC
Topic: Yet another ZX Spectrum !!
Replies: 4
Views: 1464

Re: Yet another ZX Spectrum !!

Hi Lez Looks real enough.. there was much discussion about over at VCF, although I'm pretty cynical about it myself as I have several of the real things right here, so don't really need it. Another option was mooted ( http://www.cnx-software.com/2016/02/08/k3-wintel-keyboard-pc-specs-unboxing-and-te...
by JonB
01 Jan 2016 18:08
Forum: PROGRAMMING
Topic: C & Assembler conundrum
Replies: 6
Views: 2984

Re: C & Assembler conundrum

Bill B wrote:Indirect addressing on Z80 is most efficient using HL.
I did wonder. I suppose I wanted it working first! Yes, 3 t-states with HL vs BC..

(edit:seems to be broken again. I think it is psect areas conflicting)
by JonB
01 Jan 2016 18:06
Forum: PROGRAMMING
Topic: C & Assembler conundrum
Replies: 6
Views: 2984

Re: C & Assembler conundrum

This is the problem. I am developing it on CP/M with Hi-Tech C 3.09 and there is some corruption going on. Unfortunately the manual, while detailed, doesn't give much guidance on embedding assembler inline in a C program (which this is - and I'm trying to optimise it). It seems to be stable with the...
by JonB
01 Jan 2016 17:21
Forum: PROGRAMMING
Topic: C & Assembler conundrum
Replies: 6
Views: 2984

Re: C & Assembler conundrum

Or this: #asm psect text global _Curschar global _Fileend ;Init ld bc,(_Fileend) ;p=Fileend loop1: dec bc ;p-- ld a,(bc) ;get char to be moved (swap=*p) inc bc ;copy it (p++) ld (bc),a ;..to p (*p=swap) ld h,b ld l,c ld de,(_Curschar) ;have we reached the insert point? dec bc ld a,h cp d jp nz, loop...