Hitachi 2048-word x 8-bit high speed CMOS static RAM. These have been discontinued years ago but there are still many circuits that use them. We have a very limited quantity. Prime Hitachi branded!
Features:
Single 5V supply
High Speed: Fast access time
Directly TTL compatible
Equal access and cycle time
Completely static RAM: No clock or timing strobe required
24 pin DIP.
G14750
I was going to purchase one, but I would like to look at teh datasheet first.
To access the 6116 you need to setup the 11 address lines and the data lines. You then either set /wr and /cs low to write the location or /oe and /cs low to read it. It is ideal for a relay computer as there is no multiplexed busses and 2k is probably more than enough memory. To connect it to a pic would require most of the pic I/O and so would be a bad choice.
To access the 6116 you need to setup the 11 address lines and the data lines. You then either set /wr and /cs low to write the location or /oe and /cs low to read it. It is ideal for a relay computer as there is no multiplexed busses and 2k is probably more than enough memory. To connect it to a pic would require most of the pic I/O and so would be a bad choice.
G'Day Mike,
What he could do is to use a 8255 PIO between the PIC and the [static] 6116 RAM.
As the 'relay' computer will be slow, the PIO setup/loading shouldnt slow things down.
Krumlink, Google for a 8255 PIO datasheet.
G'Day Mike,
What he could do is to use a 8255 PIO between the PIC and the [static] 6116 RAM.
As the 'relay' computer will be slow, the PIO setup/loading shouldnt slow things down.
Krumlink, Google for a 8255 PIO datasheet.
Aren't you in effect multiplexing thing by using an 8255. The simplicity of the non multiplexed bus is a definite advantage if your building a relay computer. Also, the fact that you will need ram in order to access the 8255 makes it doubly not a good idea.
Using an 8255 with a pic chip to access a 6116 would be the way to go. For a relay computer I think it would actually complicate matters. Assuming that the Harvard architecture would be the simplest to implement in relays, then having ram and rom on the simplest busses would be the way to do it.
To use any serial eeprom would further complicate matters and again would require other ram in order to implement it. You would require a loadable address counter + a bit counter, not to mention some way to shift the address out.
I'm assuming that a relay computer would have rom/ram for code, ram for variables, no stack and switches/leds for I/O.
hi Mike,
I thought Krumlink was making a pseudo 'relay' computer by using a PIC, this appears to be an incorrect conclusion. He appears to want to build a true relay computer. Good luck I say.
You are burning the midnight oil again.
That should indeed be the point. However, if you look at the link I posted on the other relay computer thread then the relay computer is the ALU and associated address/data busses. The actual memory used was silicon. Even with silicon memory the thing was still huge and not something I would like to attempt building. If you did do relay memory then you are going to be pushing the envelope at 256 bytes.
That should indeed be the point. However, if you look at the link I posted on the other relay computer thread then the relay computer is the ALU and associated address/data busses. The actual memory used was silicon. Even with silicon memory the thing was still huge and not something I would like to attempt building. If you did do relay memory then you are going to be pushing the envelope at 256 bytes.
And to be honest, it's seriously a complete waste of time and money anyway, if (for historical reasons) you wanted to see what one was like, it would be fairly easy to write a simulator on a PC.
Nigel,
You are absolutely correct, however, at his age I was going to conquer the world and be the most famous person ever. Unfortunately, I only managed half of that.
The youth of today should be encouraged at every step. Krumlink appears to have a lot of enthusiasm and gets on and does things. Let's encourage him and others to have a go.
The youth of today should be encouraged at every step. Krumlink appears to have a lot of enthusiasm and gets on and does things. Let's encourage him and others to have a go.
3V0 managed to focus Krumlink for a short while, and Krumlinks school robot (with the globe) looked great (was it a VEX?).
Krumlink appears to be driven by visual / physical projects. A microcontroller IC looks pretty meek and may appear uninteresting compared to something mechanical. **broken link removed**
Differential engine (an early mechanical computer) the meccano version is a monster. **broken link removed** This wee 12F509 device is a very power micro computer