Ti Hardware Development

[ti99/4a]

Hi.


Thought a thread dedicated to Ti Hardware Development would be useful.. For those building homebrew / DIY and professional Add-on and stuff. So if your designing a TMS9900/TMS9995 or TMS991xx system this is the place to tell everyone about it ! Everything from Ti-99/4A to Newly designed stuff and all things Ti hardware related.

 

[lezanderson]

I was thinking of doing a Feasibility Study on a New TMS9900 (TiI99/4A) Type system. Possibly with the following spec:


TMS9900 CPU clocked at 16/4MHz 16MHz input 4MHz bus, Zero wait states on RAM/ROM



TMS9900 CPU
TIM9904A Clock gen
TMS9901 PIO x 2
TMS9902 SIO x2
EPM7128SLC84 as Glue logic (possibly 2pcs)
RAM 128kx8bit x 4 pcs (512k sram 100ns or faster)
NVSRAM (DS1245 128kx8bit 2pcs) 256k byte .. 70 or 100ns
ROM
V9958 Video 192K Video RAM PAL/NTSC RGB & Composite output
SN76489 sound 2pc (Left / Right sound output)
SAA1099 Sound PSG
PS/2 keyboard/ Mouse
8255 for CF Card reader
8255 for PATA IDE interface
RTC Real Time clock
AM9511A 4MHz Maths co-processor


cost for the ICs about $40 (£28)


If it could be squeezed onto a double sided PCB (300mm x 160mm) then the PCB should only cost about £15


Connector,buttons,switches,IC sockets etc about $10 , £7


So total cost would be about £50, $75 ??


As all the ICs are still readily available it shouldn't be to difficult to source everything !




The Hard part is obviously design/testing it, and programming the CPLD (VHDL/Verilog) !!

 

[lezanderson]

Sourcing Ti TMS99xx type ICs..

I've hunted around the internet and stuff , chasing down best prices for TMS99xx ICs ... these are mainly pulls , but some may even be NOS


Prices from G&C

TMS99105 (difficult to source cheap) normally about $20 each
TMS9995 $6.50 each
TMS9900 $2.20 each
TIM9904A $2.10 each
TMS9901 $2.0 each
TMS9902 $1.40 each
TMS9911 about $2.0 each
74LS610/74LS612 about $2.0 each
TMS9909 FDC .. difficult to source


Prices from Funkward-tech

TMS9995 1pcs $8.5/EA
TMS9902 2pcs $1.5/EA
TMS9911 1pcs $6.0/EA
TMS4500 1pcs $2.0/EA
TMS4116 8pcs $1.0/EA
74LS04 5pcs $0.5/EA
74LS74 7pcs $0.5/EA
74LS86 1pcs $1.0/EA
74LS00 4pcs $0.5/EA
74LS02 3pcs $0.5/EA
74LS10 2pcs $1.0/EA
74LS244 8pcs $0.5/EA
74LS08 3pcs $0.5/EA
74LS139 3pcs $0.5/EA
74LS07 5pcs $0.8/EA
74LS164 1pcs $1.0/EA
74LS20 1pcs $1.0/EA
74LS32 4pcs $0.5/EA
74LS612 1pcs $2.0/EA
74LS27 2pcs $0.85/EA
74LS139 2pcs $0.5/EA
74LS245 2pcs $1.0/EA
74LS251 2pcs $1.0/EA
74LS259 1pcs $1.0/EA
74LS123 1pcs $0.5/EA
75189A 1pcs $1.0/EA
74LS73 1pcs $0.85/EA
75188 1pcs $1.0/EA
74LS297 1pcs $2.0/EA
74LS2001 1pcs $2.0/EA
4046B 2pcs $1.0/EA
4013 1pcs $1.0/EA
LM1889 1pcs $2.0/EA
LM339 2pcs $1.0/EA
TL08 1pcs $1.0/E

 

[Ksarul]

I have yet to see a 74LS2001 available from ANY source worldwide--and I've been hunting them for the last 10 years. None of the parts houses in North America or Europe have them. One place in Poland claimed to have them, but they actually had something else with a similar part number. I do know what the internal logic is supposed to look like, but an original chip is definitely unobtanium.

 

[lezanderson]

I have yet to see a 74LS2001 available from ANY source worldwide--and I've been hunting them for the last 10 years. None of the parts houses in North America or Europe have them. One place in Poland claimed to have them, but they actually had something else with a similar part number. I do know what the internal logic is supposed to look like, but an original chip is definitely unobtanium.

Is there VHDL or logic code available to program a GAL or CPLD to replicate a 74LS2001 functionality ?? And if so where on the web please.

** Also TMS9909 seem somewhat elusive to source, though you do see them advertised... is it possible to put a TMS9909 onto a CPLD and how many macrocells would it need ??

 

[Ksarul]

The information exists--with most of what you need on the Powertran Cortex website. It is not in VHDL format though, as no one has tried to replicate the chip in that format to date (it has been cloned in a more limited format by using discrete components).