- Wed Aug 10, 2005 8:24 pm
#6565
I've been designing my own AVR carrier board for a while now. Before I start building them, I thought I'd ask: Has anyone got a board similar to what I need for sale?
* I want a PCB (not wired; I need the reliability of PCBs. Students will be using these, and wires get pulled off.)
* I need an ISP header, and (hopefully) a JTAG connection.
* Power should come in on a standardized power connector (I perfer a 2.4 mm coaxial power connctor, but anything works.)
* The board should contain a low dropout 5V 1A-3A Vreg. I run off of 6V CR223A batteries, so the low-dropout regulator is a must.
* The board must have a power switch and power LED.
* Every I/O port will be run out to STK style 10-pin headers.
* The board should run off a high-speed crystal. 16 MHz would work, but 20 MHz would be better.
* The chip must be socketed, without any fancy SMT-to-through-hole-pin carrier boards. (I've blown 2 chips a week for the last month, and $40 carrier boards are expensive.) That leaves me with PDIP packaging.
Atmel supports 40 pin, 28 pin, 20 pin, and 8 pin PDIP packages. After reviewing the specs, I decided to start with the bigger 2 (40 pin and 28 pin.)
I started by looking for the most powerful chips in each form factor.
The most powerful chip that fits the 40 pin PDIP socket is the
AtMega644 (64K Flash, 20 MHz, 4k SRAM, 2k EEPROM, 32 I/O Pins, 3
Counters)
http://www.atmel.com/dyn/products/produ ... rt_id=3694
The most powerful chip that fits the 28 pin PDIP socket is the
AtMega168 (16k Flash, 20 MHz, 1k SRAM, 0.5k EEPROM, 23 I/O Pins, 3
Counters)
http://www.atmel.com/dyn/products/produ ... rt_id=3303
Does anyone make a board that breaks out the pins on an AVR 40 pin or 28 pin chip to STK style headers?
I put everything on boards that take 10 pin headers. I've got working boards to run RC Servos, several different H-Bridges, Relays, LEDs, Buttons, Switches, and am working on an Encoder board. I just grab a processor carrier board from a rack rack of processor boards, and a peripheral board (e.g., a Relay board) from a rack of peripheral boards, install a device driver that I write every time I build a board, and I start programming. (Man, that makes it easy!) Most of my peripheral boards work just fine off the +5V DC (100mA max) from the 10 pin IDC cable.
If not, is anyone else interested in getting PCBs made? I could use help designing the PCBs. We'll get a few made to make sure they work before we do any large quantity orders.
Thanks!
Andy Out!
P.S. I've read that 8051s are almost pin compatible with AVRs, with the exception of the RESET pin being reversed (+5V vs. Ground) is this correct? Are there any 8051s that could be programmed in-system? My thinking is to possibly allow the 40 pin board to do double duty as an 8051 board.
* I want a PCB (not wired; I need the reliability of PCBs. Students will be using these, and wires get pulled off.)
* I need an ISP header, and (hopefully) a JTAG connection.
* Power should come in on a standardized power connector (I perfer a 2.4 mm coaxial power connctor, but anything works.)
* The board should contain a low dropout 5V 1A-3A Vreg. I run off of 6V CR223A batteries, so the low-dropout regulator is a must.
* The board must have a power switch and power LED.
* Every I/O port will be run out to STK style 10-pin headers.
* The board should run off a high-speed crystal. 16 MHz would work, but 20 MHz would be better.
* The chip must be socketed, without any fancy SMT-to-through-hole-pin carrier boards. (I've blown 2 chips a week for the last month, and $40 carrier boards are expensive.) That leaves me with PDIP packaging.
Atmel supports 40 pin, 28 pin, 20 pin, and 8 pin PDIP packages. After reviewing the specs, I decided to start with the bigger 2 (40 pin and 28 pin.)
I started by looking for the most powerful chips in each form factor.
The most powerful chip that fits the 40 pin PDIP socket is the
AtMega644 (64K Flash, 20 MHz, 4k SRAM, 2k EEPROM, 32 I/O Pins, 3
Counters)
http://www.atmel.com/dyn/products/produ ... rt_id=3694
The most powerful chip that fits the 28 pin PDIP socket is the
AtMega168 (16k Flash, 20 MHz, 1k SRAM, 0.5k EEPROM, 23 I/O Pins, 3
Counters)
http://www.atmel.com/dyn/products/produ ... rt_id=3303
Does anyone make a board that breaks out the pins on an AVR 40 pin or 28 pin chip to STK style headers?
I put everything on boards that take 10 pin headers. I've got working boards to run RC Servos, several different H-Bridges, Relays, LEDs, Buttons, Switches, and am working on an Encoder board. I just grab a processor carrier board from a rack rack of processor boards, and a peripheral board (e.g., a Relay board) from a rack of peripheral boards, install a device driver that I write every time I build a board, and I start programming. (Man, that makes it easy!) Most of my peripheral boards work just fine off the +5V DC (100mA max) from the 10 pin IDC cable.
If not, is anyone else interested in getting PCBs made? I could use help designing the PCBs. We'll get a few made to make sure they work before we do any large quantity orders.
Thanks!
Andy Out!
P.S. I've read that 8051s are almost pin compatible with AVRs, with the exception of the RESET pin being reversed (+5V vs. Ground) is this correct? Are there any 8051s that could be programmed in-system? My thinking is to possibly allow the 40 pin board to do double duty as an 8051 board.