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Re: Reverse-Engineering the Speech Processor ROM [message #10689 is a reply to message #10688]

Tue, 09 April 2024 04:22

lynchaj
Messages: 1080
Registered: June 2016

Senior Member

Hi Jay
Maybe another way to look at the SPR016 emulation is the cycle time. The SP0256 is sending the ROM clock at 1.56 MHz so it has a cycle time of ~640ns. For an MCU to respond fast enough, assuming 20 instructions necessary to meet worst case SP0256 command, would be 32ns instruction time. That would translate to an MCU instruction clock of >31 MHz or approximately twice as fast as the fastest 8-bit PIC. Maybe the MSP430 can go faster or do it in fewer instructions but it will really have to be going very fast to keep up. I am thinking 64MHz or 128MHz oscillator clock speeds to really have a chance of succeeding.

I think a CPLD to parallel EPROM would have a decent chance of working. Of course, there is no harm in trying the MCU approach. Maybe there is something out there that might work. Regarding the MPS430, I just don't know because I am not familiar with it. However, to be useful it also has to be at least 5V tolerant and some form of hobbyist friendly packaging. Some SMT are OK like SSOP and SOIC but others like BGA require special tools and techniques. Maybe the MCU is available on a DIP type module which might work too.

I am really looking forward to the DAISY256 PCBs arriving though. Can't wait to see if this idea of emulating the CTS256 even works! Thanks, Andrew Lynch

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[Message index]

		General Instrument CTS256A-AL2 vs. Microchip CTS256AL2 By: lynchaj on Fri, 28 April 2023 03:28
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: jayindallas on Fri, 28 April 2023 13:10
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: scruss on Sat, 06 May 2023 16:46
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: lynchaj on Sat, 06 May 2023 18:13
		Re: github project may have extracted the CTS256A-AL2 code By: jayindallas on Sat, 06 May 2023 20:45
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: gkaufman on Sun, 07 May 2023 07:11
		Re: Programming the Naval algorithm as a CTSx for PIC/TMS7000 or otherwise By: jayindallas on Sun, 07 May 2023 16:26
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: lynchaj on Mon, 08 May 2023 04:04
		Re: Is the PIC/TMS7041 field programmable? By: jayindallas on Mon, 08 May 2023 08:25
		Re: Is the PIC/TMS7041 field programmable? By: lynchaj on Mon, 08 May 2023 12:50
		Re: No source of new-old CTS256A-AL2 economical micro solutions By: jayindallas on Mon, 08 May 2023 16:37
		Re: No source of new-old CTS256A-AL2 economical micro solutions By: lynchaj on Tue, 09 May 2023 04:41
		Re: No source of new-old CTS256A-AL2 economical micro solutions By: scruss on Sun, 14 May 2023 09:40
		Re: No source of new-old CTS256A-AL2 economical micro solutions By: jayindallas on Sun, 14 May 2023 22:19
		Re: No source of new-old CTS256A-AL2 economical micro solutions By: scruss on Wed, 17 May 2023 07:11
		Re: No source of new-old CTS256A-AL2 economical micro solutions By: jayindallas on Wed, 17 May 2023 11:03
		Emulating a TMS/PIC7000 (CTS256A-AL2) in a new MCU... By: jayindallas on Sat, 20 May 2023 09:12
		CHAPTER 01 :: "Introduction to Hardware Emulation of the 7000 Series" By: jayindallas on Sun, 21 May 2023 11:08
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: lynchaj on Mon, 25 March 2024 11:23
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: lynchaj on Wed, 27 March 2024 19:11
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: lynchaj on Sun, 31 March 2024 08:46
		7000 Series Unobtainium may be OBTAINium? By: jayindallas on Sun, 31 March 2024 11:50
		Re: General Instruments CTS256A-AL2 vs. Microchip CTS256AL2 By: lynchaj on Sun, 31 March 2024 17:38
		Tables of Various 7000 Series Device Features/Specifications By: jayindallas on Sun, 31 March 2024 19:41
		Re: TMS7000 Series Devices (Manual section 2.1) By: lynchaj on Mon, 01 April 2024 12:01
		Prototyping 7xxx Devices appear to support External Memory?! By: jayindallas on Mon, 01 April 2024 18:37
		Re: TMS7000 Series Devices (Manual section 2.1) By: lynchaj on Wed, 03 April 2024 03:57
		Re: TMS7000 Series Devices (Manual section 2.1) By: lynchaj on Thu, 04 April 2024 04:59
		CTS256 resurrection from old 70xx & SP-0256* too?! By: jayindallas on Thu, 04 April 2024 08:56
		Re: TMS7000 Series Devices (Manual section 2.1) By: lynchaj on Thu, 04 April 2024 10:00
		70x1 Memory Access Timing: Internal -versus- External Access By: jayindallas on Thu, 04 April 2024 11:03
		Re: 70x1 Memory Access Timing: Internal -versus- External Access By: lynchaj on Fri, 05 April 2024 06:07
		TMS7000 Series with Custom Micro-Coded Instructions By: jayindallas on Fri, 05 April 2024 21:14
		Re: TMS7000 Series with Custom Micro-Coded Instructions By: lynchaj on Sat, 06 April 2024 16:52
		Daisy 256 & the Speech Processor By: jayindallas on Sat, 06 April 2024 21:32
		Re: Daisy 256 & the Speech Processor By: lynchaj on Sun, 07 April 2024 07:08
		Reverse-Engineering the Speech Processor ROM By: jayindallas on Sun, 07 April 2024 11:24
		Re: Reverse-Engineering the Speech Processor ROM By: lynchaj on Sun, 07 April 2024 18:13
		Re: Reverse-Engineering the Speech Processor ROM By: lynchaj on Mon, 08 April 2024 03:46
		Re: Reverse-Engineering the Speech Processor ROM By: jayindallas on Mon, 08 April 2024 14:23
		Re: Reverse-Engineering the Speech Processor ROM By: lynchaj on Tue, 09 April 2024 04:22
		Re: Reverse-Engineering the Speech Processor ROM By: lynchaj on Tue, 09 April 2024 09:49
		Re: Reverse-Engineering the Speech Processor ROM By: lynchaj on Tue, 09 April 2024 10:50
		Re: Reverse-Engineering the Speech Processor ROM By: jayindallas on Wed, 10 April 2024 20:40
		Re: Reverse-Engineering the Speech Processor ROM By: lynchaj on Thu, 11 April 2024 09:56
		Re:TMS700x Memory Interface Mode Timing Spreadsheet UPDATE By: jayindallas on Fri, 12 April 2024 08:16
		Re: What TMS7000 Family Data Manual Version Am I Using? By: lynchaj on Fri, 12 April 2024 13:54
		Re: What TMS7000 Family Data Manual Version Am I Using? By: lynchaj on Fri, 19 April 2024 03:37
		DAISY256 works By: lynchaj on Mon, 22 April 2024 03:36
		Re: DAISY256 works By: lynchaj on Mon, 22 April 2024 12:57
		Re: DAISY256 works By: lynchaj on Mon, 22 April 2024 15:10
		Re: DAISY256 works By: lynchaj on Tue, 23 April 2024 03:54
		Re: DAISY256 works By: lynchaj on Tue, 23 April 2024 12:02
		Re: DAISY256 works By: jayindallas on Tue, 23 April 2024 12:31
		Re: DAISY256 works By: lynchaj on Sat, 27 April 2024 12:12
		Baud Rate Tables for 70x1, 70x2, 70Cx2 By: jayindallas on Sun, 28 April 2024 21:43
		Re: DAISY256 works By: lynchaj on Mon, 29 April 2024 04:16
		Re: DAISY256 works By: plasmo on Mon, 29 April 2024 05:52
		Re: DAISY256 works By: jayindallas on Mon, 29 April 2024 15:09
		Re: DAISY256 works By: plasmo on Mon, 29 April 2024 20:25
		Re: DAISY256 works By: lynchaj on Tue, 30 April 2024 04:44
		Re: DAISY256 works By: berzerkula on Mon, 06 May 2024 19:31
		Re: DAISY256 works By: lynchaj on Tue, 07 May 2024 04:50
		Re: DAISY256 works By: berzerkula on Tue, 14 May 2024 22:37
		Re: DAISY256 works By: lynchaj on Wed, 15 May 2024 03:38
		Re: DAISY256 works By: scruss on Wed, 24 July 2024 15:46
		Re: DAISY256 works By: berzerkula on Tue, 26 November 2024 17:17
		Re: DAISY256 works By: lynchaj on Sun, 16 June 2024 11:21
		Re: DAISY256 works By: berzerkula on Mon, 15 July 2024 23:57

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