Basically just breakout boards for an ATmega644/1284.
I have built several testers based on the Atmega328, and want to expand it.
I would like to incorporate the various adapters, ( opto, options etc)
Is there up to date docs on this?
Karl-Heinz' documentation would be the best place to start. It includes two circuits for the 644/1284 and most options. I'll attach the schematic of my 644/1284 dev board. The nice thing besides the additional I/O pins is that we can use hardware I2C and SPI. The pin assignment of the 328 based tester doesn't permit that. The basic pin assignment for the 644/1284 is:
Port A: ADC
- PA0: Probe #1
- PA1: Probe #2
- PA2: Probe #3
- PA3: V external (Zener)
- PA4: 2.5V reference
- PA5: V battery
- PA6: unused
- PA7: Probe for fixed 100nF cap for auto-adjustment
Port D: resistors and serial
- PD0: RXD0
- PD1: TXD0
- PD2: TP1 R_Low
- PD3: TP1 R_High
- PD4: TP2 R_Low
- PD5: TP2 R_High
- PD6: TP3 R_Low
- PD7: TP3 R_High
Port C: controls and I2C
- PC0: I2C (SCL)
- PC1: I2C (SDA)
- PC2:
+ frequency counter: 16:1 divider
+ parallel cap for SamplingADC
- PC3:
+ frequency counter: Input Select P0
+ rotary encoder A
- PC4:
+ frequency counter: Input Select P1
+ rotary encoder B
- PC5: Rh for fixed 100nF cap (auto-adjustment)
- PC6: power control
- PC7: push button
Port B: HD44780 display
- PB0: frequency counter: f in
- PB1: unused
- PB2: RS
- PB3: E
- PB4: D4
- PB5: D5
- PB6: D6
- PB7: D7
Port B: SPI display
- PB0: frequency counter: f in
- PB1: unused
- PB2: /Reset
- PB3: Data/Command
- PB4: /CS
- PB5: MOSI
- PB6: MISO
- PB7: SCK
There are also ideas to extend the B port with one or two 74HC595 for driving displays and other things.
It's a "IC Transistor Tester Detect Meter Maintenance Digital led Tester MOS PNP NPN "
It tests 74xx and 4xxx chips.
That's a completely different tester. Some do also a few OPamps and other ICs.