Interfacing The MCBx51

Jon, I am frustrated. Please address my question. Mabe you shuld read it again. I also asked this question by phone and recieved basically the same reply via E-Mail. Of course I have examined the board schematics and understand them FULLY.


Does your Mother Company not allow you to give out example scematics?

signed....

A current registered owner of PK51

David P. Mitchell

Jon, I am frustrated. Please address my question. Mabe you shuld read it again. I also asked this question by phone and recieved basically the same reply via E-Mail. Of course I have examined the board schematics and understand them FULLY.


Does your Mother Company not allow you to give out example scematics?

signed....

A current registered owner of PK51

David P. Mitchell

Please address my question. Mabe you shuld read it again. I also asked this question by phone and recieved basically the same reply via E-Mail. Of course I have examined the board schematics and understand them FULLY.

Dear David,

I'm sorry you are frustrated with this problem. Our support personnel spend a great deal of time helping customers use our products. They do not have any extra time to spend teaching how to design schematics or write programs.

Fortunately, we offer training courses that do address these topics. While we don't get into teaching how to use schematic capture software, the classes are tailored to the students ( http://www.keil.com/training ). I'm sure we could accommodate your request to wire-up an I/O device with the MCBx51 board.

I cannot provide you with schematics for an I/O device using the CS for E400-E7FF. However, I can provide you with a few tips:

• The CS for address range E400-E7FF is dedicated to the off-chip UART (16550). If you want to use it you need to remove the 16550 (to avoid bus contention).

• There is a User CS for the address range E000-E3FF. It is not attached to anything and it is brought out to the port signals row. Maybe this is a better choice for a CS.

• Connect the /WR pin of your I/O device to P3.6 (/WR) on the port signals row.

• Connect the /RD pin of your I/O device to the /RD_RAM pin from the CAL (pin 15). Don't solder directly to the GAL. You may want to remove the GAL if you are soldering near it.

• Connect the address bus (as needed) to your I/O devices. These are provided on the port signals row.

• Connect the data bus to your I/O devices. These are provided on the port signals row.

• Connect VCC and GND to your I/O device.

#include <absacc.h>
void main (void)
{
while (1)
  {
  XBYTE[0xE000]=0xAA;
  }
}