Thread: Hitachi HM6116ZP-4 CMOS RAM Datasheet

Originally Posted by Pommie

We were all that enthusiastic once and shouldn't knock it. However, your probably right.

Considering this
Googl the BEAM Light seeker
is about as far as he goes, I can't see him building anything like a relay based computer

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.

Originally Posted by Nigel Goodwin

But the 8255 is a really limited 'horrible' device, there are MUCH better PIO chips available (like the 6522 for a start).

But considering this is supposed to be for a 'relay computer', isn't the memory supposed to made of relays? - isn't that the point?.

hi Nigel,
I did say in the 'past', I suppose I should I should have said, 'in the distant past'.
Remember at one time time, it was cutting edge!.

Originally Posted by Pommie

Nigel,

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.

Mike.

Mike,

For whats its worth, I agree 100%

I achieved most of my goals and I try to help others to do the same...

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.

Differential engine (an early mechanical computer) the meccano version is a monster.

This wee 12F509 device is a very power micro computer

Originally Posted by blueroomelectronics

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.

I still study PIC mcu and I am still very much interested in it. The robot was built out of scratch, no prefab parts (I hate lego and vex because of this). I LOVE PIC and mcu, it is just understanding a 2nd language is hard, aka C (I know english, leet and learning c )

Originally Posted by Nigel Goodwin

Considering this
Googl the BEAM Light seeker
is about as far as he goes, I can't see him building anything like a relay based computer

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.

UH NIGEL? HELLO BINARY CLOCK???

So, at what speed will the SRAM output? will it just spew out data as fast as possible or at a set speed?

(I am thinking it output's at the clock speed)

Originally Posted by Krumlink

So, at what speed will the SRAM output? will it just spew out data as fast as possible or at a set speed?

(I am thinking it output's at the clock speed)

It will output just as fast as you ask it to, you set it's address lines, and it outputs the data from that address on the data lines. It's a static RAM (CMOS so can be battery backed) so can be run as slow as you like.

I've got an old Microtan 65 memory card with battery backed 6116's on, from years and years ago.

So how do I set it's speed lol

Originally Posted by Krumlink

So how do I set it's speed lol

You don't really, you set it's address lines, and the output reflects what's in that address - so how fast you change the address lines sets the speed.

My work with Krumlink has been plagued by equipment problems on his end. Once we got that sorted he was too busy to keep appointments.

Krumlink has too many irons in the fire. We postponed further study till after the FIRST robotic competitions are over. Maybe till after school is out.

When things are less hectic and he has the time to be serious about learning we will try again.

Originally Posted by blueroomelectronics

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.

Originally Posted by Nigel Goodwin

You don't really, you set it's address lines, and the output reflects what's in that address - so how fast you change the address lines sets the speed.

Ok! So I send in the clock signal into the address lines to change it, and it changes lines at that speed?

Edit: so this is where the finite state machine comes in?

Uh that was a question, I send in the signal to change address lines?

Originally Posted by Krumlink

Uh that was a question, I send in the signal to change address lines?

hi,
If you used a 8255 PIO to connect to the 6116 SRAM, you would do the following write/read sequence.

Change the PIO's portA to output.
Set the PIO's portA to say the 8 bit data you want to write to the SRAM.
Then set the PIO's portB and portC[low nibble] to the the address [location] in the SRAM where you want the data on portA to be written.
Then set the SRAM WR and CS low and high,[using portC[high nibble] this will write the data to the addressed SRAM location.

For reading the SRAM,
Change the PIO's portA to input.
Then set the PIO's portB and portC[low] to the the address [location] in the SRAM where you want the data on portA to be read from
Then set the SRAM CS low and high, this will place the data of the addressed SRAM location onto the portA, which the program then reads.

As you can see, the write/read cycle is much longer than the 'clock' rate.

It would help if you could post a block diagram of your project.