Outputs 9-17?

[timr92]

Hi,
I have a feeling i am going to feel really stupid once i get an answer to this question, but here goes... How on earth would i use more than 8 outputs on a 28X part for example? And can i use the "let pins = %..." thing for more than 8 outputs?
I've looked everywhere, but the stupid manuals say everything has to be a number between 0 and 7...
Thanks in advance!

Tim

 

[westaust55]

There are 8 outputs numbered 0 to 7 which is PIC(AXE) PortB and are preset as outputs and work with most of the output commands such as SEROUT, SHIFTOUT, HIGH and LOW.

The other 8 pins you mention are on the PortC pins which be defaults are used as inputs on the 28X1.

Some newer commands/functions such as I2Cxxxxx and HI2Cxxxx , SPI, HSEROUT and HSERIN also use some of the PortC pins when these functions are required.


For the PortC pins, other than the HSEROUT & HSERIN commands (which is fixed to the portC pins C6 and C7), other commands such as
SHIFTOUT, PULSOUT, SEROUT etc are only for the PortB OUTPUTS and will not operate on Port C.


Commands (other than i2c and spi functions, PWM1/2 with dedicated port C pin allocations on the 28X1) that will work with PortC are:
DIRSC, HIGH PORTC, LOW PORTC, PINSC


Assuming you might have an AXE020, then using the attached picture as a reference,
- The orange outlined pins are the Analogue Inputs on Port A
- The yellow outlined pins are the Digital Inputs on Port C
- The pink outlined holes are the Digital Outputs on Port B
- The tan outlined holes are the Darlington Transistor Ouputs driven from port B

 

[inglewoodpete]

And you can use an output expander chip like 1 or more 74HC595s to provide further output pins, especially when you need those input / port C pins for other things.

 

[westaust55]

Think the original request came more from Manual 1 page 12 where it states:

Standard: (600/1000 lines memory)

18X 5 inputs 8 outputs 3 ADC 8MHz
28X1 0-12 inputs 9-17 outputs 0-4 ADC 20MHz
40X1 8-20 inputs 9-17 outputs 3-7 ADC 20MHZ​

The inform sought is in the manual 1 at pages 81 and 82 where covers using PortC as outputs.