Search found 12 matches
- Sat Apr 21, 2018 2:04 am
- Forum: Hardware
- Topic: ZX81 I/O interface for your projects
- Replies: 27
- Views: 22351
Re: ZX81 I/O interface for your projects
I'm also looking for ideas or perhaps a schematic with docs for using the HC-SR204 Ultrasonic Transceiver Board. I will be using 3 of the boards as part of the navigation/object avoidance system... I already have a working Infrared system working that will provide additional control to the navigatio...
- Sat Apr 21, 2018 1:57 am
- Forum: Hardware
- Topic: ZX81 I/O interface for your projects
- Replies: 27
- Views: 22351
Re: ZX81 I/O interface for your projects
I'll be using the 8 bit data bus so what I am looking for is 8 bits in and 8 bits out,but with the inclusion of device select codes, one for each device to turn it off or on to send or receive data...simple,but effective... I'm looking for a schematic of what I stated above,but if you have something...
- Fri Apr 13, 2018 2:51 am
- Forum: Hardware
- Topic: ZX81 I/O interface for your projects
- Replies: 27
- Views: 22351
Re: ZX81 I/O interface for your projects
Thanks for all the help...I have tons of 74LSXX and 74HCTXX,and since I'm looking for the
greatest amount of power conservation in a robotics project,74HCT Series it is...
Now to decide between the Z84C20 PIO which I have 20 or to use the 82C55 as device
controllers??
greatest amount of power conservation in a robotics project,74HCT Series it is...
Now to decide between the Z84C20 PIO which I have 20 or to use the 82C55 as device
controllers??
- Sun Apr 08, 2018 9:11 pm
- Forum: Hardware
- Topic: ZX81 I/O interface for your projects
- Replies: 27
- Views: 22351
Re: ZX81 I/O interface for your projects
In designing any peripheral what is the logic family of choice,74LS,74HC,or 74HCT??
- Fri Apr 06, 2018 9:29 pm
- Forum: Hardware
- Topic: ZX81 I/O interface for your projects
- Replies: 27
- Views: 22351
Re: ZX81 I/O interface for your projects
Definitely a very nice I/O Board...I do ask tho' would this be for a single peripheral board to control
such as a AY3-8910,12,SPO256A-AL2 addon? I ask because I saw that has no expansion device select coding
for multiple add ons?
such as a AY3-8910,12,SPO256A-AL2 addon? I ask because I saw that has no expansion device select coding
for multiple add ons?
- Tue Feb 20, 2018 1:39 am
- Forum: Hardware
- Topic: Internal RAM upgrade
- Replies: 10
- Views: 10158
Re: Internal RAM upgrade
Thanks for clearing up my mystery Siggi...
- Tue Feb 13, 2018 9:43 pm
- Forum: Hardware
- Topic: Internal RAM upgrade
- Replies: 10
- Views: 10158
Re: Internal RAM upgrade
Thank you for the info... I'm looking at the barebones 64K upgrade without the Rom Patch is that the same diagram you are referencing?? Also would it be necessary to connect the /RD to the /OE?? Just trying to keep board size and designing to a minimum...I am assuming that all the diodes referenced ...
- Mon Feb 05, 2018 9:31 pm
- Forum: Hardware
- Topic: Source for 40pin DIP Heatsink?
- Replies: 9
- Views: 5514
Re: Source for 40pin DIP Heatsink?
Heatsink silicone is an obvious need whenever heatsinks are used for thermal transfer...
- Mon Feb 05, 2018 9:20 pm
- Forum: Hardware
- Topic: Internal RAM upgrade
- Replies: 10
- Views: 10158
Re: Internal RAM upgrade
So what would you suggest for a bare bones 64K upgrade to a Zeddy??
I am building a parabot,(everyone else would call it a robot),I have a
8K NVRAM board already completed that will be in the 8192-16384 region to
which I will use for the machine code routines...
I am building a parabot,(everyone else would call it a robot),I have a
8K NVRAM board already completed that will be in the 8192-16384 region to
which I will use for the machine code routines...
- Mon Feb 05, 2018 3:33 am
- Forum: Hardware
- Topic: Internal RAM upgrade
- Replies: 10
- Views: 10158
Re: Internal RAM upgrade
I found 2 64K upgrade wihich are of Wilf's and thought they would be easier to construct and implement...