Re: TransWarp GS repair questions

[Conrad <conrad.russo@gmail.com>]

Hi guys,

So I placed an order for everything besides the power supply yesterday. I will be ordering the supply shortly. Here is what I picked up:

Genius G540 Universal Programmer
No Name EPROM Eraser
W65C816S6PLG-14 CPU 
3 CY7C199CN-15PXC 15ns .3 wide SRAM
Gold plated machine pin sockets

I decided to not order the 70ns SRAMs since from what Steven said and I've read they would most likely just be useless. I plan to mount the sockets in the same way most people mount the SRAMs to the board, with the legs bent to 90 degrees and lengthened to reach the .6 wide through-holes. As I mentioned before I have a professional grade vacuum pump desoldering station, so I will properly desolder the old SRAMs instead of cutting them out at the chip and using the leads to connect direct to the new chips like some people suggest doing. Since I can I feel its better to keep the old ones then to destroy them in the removal process. The power supply that I plan to buy has the following specs:

Voltage +5V -5V +12V -12V +3.3V +5V-SB 
Current 15A 0.5A 16A  0.8A 15A     2.5A

Wayyyyy more than enough for the GS but I figure that is the best way, since once I install that, there will be no risk of too much draw on the supply ever again. Hopefully, all of these upgrades and tweaks will fix whatever is causing the issues. If not... time to break out the rework station and the logic probe and really get my hands dirty. The CPU, SRAMs, and sockets will arrive probably Monday and the programmer and eraser will come in a few weeks. I chose the Genius G540 over the TOP853 because of various issues people have had with the latter. Anyway, I'll let everyone know how it well it goes. If the programmer works well I will offer programming of ROMs, uControllers, and PAL/GALs for the community. Results to follow soon!

Conrad