Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
03/10/08 09:48
Read: times


 		 #152063 - responses
Responding to: ???'s previous message
The EEprom uses SPI.

The LCD display uses the EIA232 standard with +/- voltages
so I will need an extra RS232 chip to communicate with it.
It does not have a SPI or I2C interface just RS232 and TTL at 19200 baud. The TTL is straight 0 to 5V.
I hate bit banging to a specific frequency or baud rate, would much rather use the published charts on setting up the baud rate by setting some registers and using the SBUF as the output. Are there some guldelines to determining the exact output given the clock frequency of the CPU (12 MHz) and the device ATMEL AT89c4051 and not using the SBUF for output?

I don't have time on this project to learn a new chip, buy the programmer or development platform, learn how to use said platform and complete the project on time.

List of 32 messages in thread
TopicAuthorDate
One RS232 port and two devices            01/01/70 00:00      
   Almost certainly not!            01/01/70 00:00      
      neither one talks back            01/01/70 00:00      
         Soft-UART ?            01/01/70 00:00      
         Simplex            01/01/70 00:00      
            responses            01/01/70 00:00      
               The beaty of the 8051            01/01/70 00:00      
                  why all this about bit-banging            01/01/70 00:00      
               Bit banging UART TX.            01/01/70 00:00      
                  Easy to get wrong.            01/01/70 00:00      
                     Point taken, but you can calculate delay.            01/01/70 00:00      
                        Depends on compiler/etc...            01/01/70 00:00      
                           Don't use HLL!            01/01/70 00:00      
                              Cycle counting.            01/01/70 00:00      
                                 Fundamental flaw            01/01/70 00:00      
                              Not an Absolute....            01/01/70 00:00      
                                 RE: Never is a strong word            01/01/70 00:00      
                                    ... and            01/01/70 00:00      
                              assembly verses HLL            01/01/70 00:00      
                           Use a Timer IRQ to set the soft baudrate            01/01/70 00:00      
                              Surprise.            01/01/70 00:00      
                                 High risk            01/01/70 00:00      
                                    Straying into fantasy.            01/01/70 00:00      
                                       Not so fantastic?            01/01/70 00:00      
                  Resistance is too high            01/01/70 00:00      
                  Another reason why this is not so easy...            01/01/70 00:00      
               Timescales            01/01/70 00:00      
      message formatting            01/01/70 00:00      
         Try it now            01/01/70 00:00      
            It's OK now, thanks.            01/01/70 00:00      
   Two RS232 devices            01/01/70 00:00      
      the LCD display            01/01/70 00:00      

Back to Subject List