Re: Forth in VHDL

From	Cecil Bayona <cbayona@cbayona.com>
Newsgroups	comp.lang.forth
Subject	Re: Forth in VHDL
Date	2016-07-24 22:58 -0500
Organization	A noiseless patient Spider
Message-ID	<nn42ph$s48$1@dont-email.me> (permalink)
References	<nn3ti7$hte$1@dont-email.me> <d961466f-cd7f-4fb2-87cf-f1b0fbd796fb@googlegroups.com> <3fcf3f54-fbe5-45c7-91c1-f33f1d7f3ab3@googlegroups.com>

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On 7/24/2016 10:33 PM, Brad Eckert wrote:
> On Sunday, July 24, 2016 at 8:08:36 PM UTC-7, Brad Eckert wrote:
>> The J1 (http://excamera.com/sphinx/fpga-j1.html) is a small CPU written
>> in Verilog. I'd study that as a start.
>>
> You'll notice that its ISA's jumps only span 8K words. Roomy enough for a nice app, but you can easily jump to anywhere in the 64Kx16 address space by defining a word such as LJMP #k16, which would expect the 16-bit data k16 immediately following the call. Sure it's slower than a direct jump, but the CPU will spend most of its time below the 8K mark.
>
> So, you really have a 128K byte address space. You could get creative with a cheap SPI flash, perhaps use some of it for high level code, some of it for BLOCK data storage. The only tricky think I see is inserting wait states to make the J1 wait for the memory interface.
>
You can also push a number into the stack move it to the return stack 
then return, that will jump anywhere in the address space. Kind of long 
but you would only use it on rare occasions. The J1 can also execute 
multiple operations on one instruction so it might be possible with one 
opcode.

-- 
Cecil - k5nwa

Thread

Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-24 22:29 -0400
  Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-24 23:01 -0400
    Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-24 23:05 -0400
      Re: Forth in VHDL Cecil Bayona <cbayona@cbayona.com> - 2016-07-24 22:25 -0500
        Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 00:08 -0400
          Re: Forth in VHDL Cecil Bayona <cbayona@cbayona.com> - 2016-07-24 23:57 -0500
            Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 01:22 -0400
              Re: Forth in VHDL Paul Rubin <no.email@nospam.invalid> - 2016-07-24 22:38 -0700
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 01:53 -0400
                Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-25 05:31 -0700
                Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-25 05:36 -0700
                Re: Forth in VHDL Richard Owlett <rowlett@cloud85.net> - 2016-07-25 08:14 -0500
                Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-25 07:37 -0700
                Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-25 08:01 -0700
              Re: Forth in VHDL Cecil Bayona <cbayona@cbayona.com> - 2016-07-25 14:11 -0500
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 17:39 -0400
                Re: Forth in VHDL Cecil Bayona <cbayona@cbayona.com> - 2016-07-25 18:01 -0500
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 19:40 -0400
                Re: Forth in VHDL Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-07-26 11:04 +0100
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-26 11:13 -0400
                Re: Forth in VHDL anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-07-26 16:00 +0000
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-26 12:58 -0400
                Re: Forth in VHDL anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-07-27 09:39 +0000
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-27 10:01 -0400
                Re: Forth in VHDL Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-07-27 22:46 +0100
                Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-26 09:43 -0700
                Re: Forth in VHDL Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-07-28 09:12 +0100
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-28 05:04 -0400
                Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-28 07:56 -0700
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-28 13:04 -0400
                Re: Forth in VHDL Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-08-02 12:21 +0100
                Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-28 08:02 -0700
    Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-27 18:15 -0400
      Re: Forth in VHDL Brad Eckert <hwfwguy@gmail.com> - 2016-07-28 15:19 -0700
        Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-31 18:43 -0400
          Re: Forth in VHDL Paul Rubin <no.email@nospam.invalid> - 2016-07-31 17:10 -0700
  Re: Forth in VHDL Brad Eckert <hwfwguy@gmail.com> - 2016-07-24 20:08 -0700
    Re: Forth in VHDL Brad Eckert <hwfwguy@gmail.com> - 2016-07-24 20:33 -0700
      Re: Forth in VHDL Cecil Bayona <cbayona@cbayona.com> - 2016-07-24 22:58 -0500
        Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 00:17 -0400
          Re: Forth in VHDL Brad Eckert <hwfwguy@gmail.com> - 2016-07-25 10:02 -0700
            Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 14:13 -0400
              Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 14:17 -0400
              Re: Forth in VHDL Brad Eckert <hwfwguy@gmail.com> - 2016-07-25 15:04 -0700
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 19:28 -0400
                Re: Forth in VHDL Brad Eckert <hwfwguy@gmail.com> - 2016-07-25 17:20 -0700
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-25 23:07 -0400
                Re: Forth in VHDL Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-07-26 03:07 -0500
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-26 13:05 -0400
                Re: Forth in VHDL Brad Eckert <hwfwguy@gmail.com> - 2016-07-26 16:22 -0700
                Re: Forth in VHDL Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-07-27 03:57 -0500
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-27 10:34 -0400
                Re: Forth in VHDL Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-07-27 11:15 -0500
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-27 12:51 -0400
                Re: Forth in VHDL Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-07-27 16:12 -0500
                Re: Forth in VHDL "Elizabeth D. Rather" <erather@forth.com> - 2016-07-27 12:43 -1000
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-28 00:40 -0400
                Re: Forth in VHDL hughaguilar96@gmail.com - 2016-08-02 22:45 -0700
                Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-28 00:39 -0400
  Re: Forth in VHDL wzab01@gmail.com - 2016-07-25 01:48 -0700
  Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-25 05:57 -0700
    Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-07-25 06:02 -0700
    Re: Forth in VHDL Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-07-30 16:40 +0100
      Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-08-01 08:58 -0700
    Re: Forth in VHDL rickman <gnuarm@gmail.com> - 2016-07-31 17:10 -0400
      Re: Forth in VHDL JUERGEN <epldfpga@aol.com> - 2016-08-01 09:02 -0700
  Re: Forth in VHDL Ilya Tarasov <ilya74.tarasov@gmail.com> - 2016-07-29 05:42 -0700

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