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Re: TMS7000 Series Devices (Manual section 2.1) [message #10648 is a reply to message #10647]

Mon, 01 April 2024 12:01

lynchaj
Messages: 1080
Registered: June 2016

Senior Member

Hi
On the duodyne project, there is a board I am currently working on with a CTS256 & SP0256 text-to-speech system along with dual SN76489 programmable sound generators and an ADC/DAC pair.

The CTS256 & SP0256 text-to-speech seems to work OK. At least I can get it to start and can hear it work. It is the full complement of IO as suggested by Radio Shack; serial port, parallel IO, expansion/exception EPROM, buffer SRAM, and UART PARMs register.

I am thinking this basic design can be modified nearly any TMS7xxx microcontroller. Especially TMS7xx1 or TMS7xx2 since they have the serial port. Possibly the TMS7xx0 series if you use only the parallel IO for input. As of now, we've been using the serial port exclusively for build and test because there is a debug monitor which has proven invaluable in debugging the system.

The CTS256 uses a simple memory mapping architecture so all the devices show up as regions of memory. Each device gets its own 4KB of memory. It is rather wasteful (IMO) but it was meant to be done on the cheap "back in the day" for low-cost commercial appeal. Can't fault them for that.

My plan is to make a new board solely to test the theory of external boot firmware. I don't see it using any other pins other than the ones it is currently using for the expansion EPROM and buffer SRAM options. Both seem to work just fine as best I can tell.

The board I am designing is called DAISY256. Not an April Fools Day joke. I am going to order some PCBs and build the design. If anyone wants to join me, please PM or email me.

Thanks, Andrew Lynch

PS, I'll send you a 160x100mm PCB for free if you will help with build and test

PPS, what I am proposing with DAISY256 is somewhat like the SE70P162. However, that piggy-back MCU chip is even more scarce that CTS256s. There seem to be very few in existence at all and even fewer for sale. Would be nice for debugging but not a suitable replacement for CTS256. We need something cheap and common as dirt to really move the extortionary prices of CTS256s down.

[Updated on: Mon, 01 April 2024 12:19]

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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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