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Quote from: woodchips on August 22, 2016, 05:55:06 pmNice, I like the 6809. Another rare, or invisible, chip was the 6840 floppy controller. Did anyone ever get one?The floppy controller was the MC6843. It was not very popular, but it was definitely produced (I have at least one). The MC6840 was a triple timer.
Nice, I like the 6809. Another rare, or invisible, chip was the 6840 floppy controller. Did anyone ever get one?
Quote from: edavid on August 22, 2016, 07:03:04 pmQuote from: woodchips on August 22, 2016, 05:55:06 pmNice, I like the 6809. Another rare, or invisible, chip was the 6840 floppy controller. Did anyone ever get one?The floppy controller was the MC6843. It was not very popular, but it was definitely produced (I have at least one). The MC6840 was a triple timer.I also used the MC6843. I implemented my own driver so that it emulated the discrete floppy controller card in the original MC6800 development systems, and allowed the Motorola development tools to be run on a wider range of hardware.
...However, the mmu capability of the gime *is* well documented and my github repository has a functional equivalent coded in vhdl.Neal
https://github.com/nealcrook/multicomp6809/blob/master/multicomp/Components/MMAPPER2/mem_mapper2.vhdNote that this code is not register compatible with the gime mmu, but is (afaik) functionally compatible.Neal
Fitter Status Successful - Wed Aug 24 21:32:55 2016Quartus II 64-Bit Version 13.0.1 Build 232 06/12/2013 SP 1 SJ Web EditionRevision Name mem_mapper2Top-level Entity Name mem_mapper2Family MAX IIDevice EPM240T100C4Timing Models FinalTotal logic elements 235 / 240 ( 98 % )Total pins 43 / 80 ( 54 % )Total virtual pins 0UFM blocks 0 / 1 ( 0 % )
Edit: Note a MaxII EPM240 is NOT 5v tolerant
6809 CamelForth v1.1 20 Mar 16OK HEXOK 1000 1FFF PASSOK HEXOK 1000 1FFF 10 PASSES ................OK HEXOK 0800 CFFF 10 PASSES ................OK
6809 CamelForth v1.1 20 Mar 16OKFLEX FLEX......................FLEX 9.0DATE (MM,DD,YY)? 09,04,16++++++dirDIRECTORY OF DRIVE NUMBER 0DISK: FLEX09BT #0 CREATED: 27-JUN-97FILE# NAME TYPE R BEGIN END SIZE DATE PRT 1 FLEX .COR 25-41 26-0E 22 27-JUN-97 2 SD .BIN 29-17 29-17 1 17-JUL-97 3 CONS .BIN 29-18 29-18 1 17-JUL-97 4 WINDRV .CMD 01-1F 01-20 2 27-JUN-97 5 ASN .CMD 01-21 01-21 1 27-JUN-97 6 TIMERON .CMD 01-22 01-22 1 27-JUN-97 7 TTYSET .CMD 01-23 01-24 2 27-JUN-97 8 DATE .CMD 01-25 01-26 2 27-JUN-97 9 ERRORS .SYS R 01-27 01-47 33 27-JUN-97 .. .. ..
The 6809 is largely an improved 6502, adopting the 6502 improvements and adding more on top.
QuoteThe 6809 is largely an improved 6502, adopting the 6502 improvements and adding more on top.Can you elaborate ? In which regard is the'09 an improved 6502 instead of an improved 6800 ?
If you can program a 6800 in assembler you won't have many problems , switching to a 6502.
I used a SN74LS610 MMU from Texas Instruments. ... I was thinking, since the 74LS610 and the MC6809 chips are very available on eBay, at least my design could be built by a few people.
Quote from: bingo600 on September 07, 2016, 05:59:24 pmIf you can program a 6800 in assembler you won't have many problems , switching to a 6502.All the addressing modes, etc., are completely different.Two accumulators, 16-bit addressing registers (LEA instructions), two stacks...A 6502 would feel really restricted after using a 6809.You could switch over, sure, but I don't think knowing 6809 would give you any special advantages over knowing any other assembly language of the era.
I have done some work with an fpga-based 6809 system and ported a bunch of pre-existing software, some of which might be of interest to you:"buggy" a debug monitor with line assembler/disassembler"FLEX" the swtp OS"NitrOS9" a open source OS9 rewrite"FUZIX" an open-source unix for small systems
I think it was mainly because of Motorola's lack of focus. They were more diversified company (radios thru all sorts of semiconductors) while MOS Technologies, Zilog and Intel were mostly microprocessor companies.
The 6809 stood out the rest by its neat and extensive instruction set that was a pleasure to use. There was even a kind of instruction that acted as kind of a pointer to a pointer. Very handy for lookup tables.
Quote from: PuterGeek on May 31, 2016, 08:36:53 pmI think it was mainly because of Motorola's lack of focus. They were more diversified company (radios thru all sorts of semiconductors) while MOS Technologies, Zilog and Intel were mostly microprocessor companies.This was my experience at the time when evaluating the 68HC11 via the 68HC811 and 64HC24 port replacement unit. Availability was so poor that we abandoned and anything from Motorola which was not second sourced. As someone mentioned, the 68008 should have been available with the 68000 but Motorola just did not seem interested in having IBM as a customer.
Quote from: David Hess on November 18, 2016, 07:23:38 amQuote from: PuterGeek on May 31, 2016, 08:36:53 pmI think it was mainly because of Motorola's lack of focus. They were more diversified company (radios thru all sorts of semiconductors) while MOS Technologies, Zilog and Intel were mostly microprocessor companies.This was my experience at the time when evaluating the 68HC11 via the 68HC811 and 64HC24 port replacement unit. Availability was so poor that we abandoned and anything from Motorola which was not second sourced. As someone mentioned, the 68008 should have been available with the 68000 but Motorola just did not seem interested in having IBM as a customer.Was that around 1994, when Motorola was cracking up from its own success? They did so well with design ins for HC11 and HC05 devices in the previous couple of years that they lacked the production capacity to service those customers when it came to mass production. The repercussions of that made many designers stay away from Motorola parts for a long time.