wyofreeride
New member
I am using a 633 serial LCD in a microprocessor based MP3 player project at school. The LCD will be used for status display and controlling the microprocessor through menus in software. I am using a Motorola HCS12. The board that we are using has a RS-232 converter on the board.
The problem that I am having is that when I send data to the LCD, I receive no response. (I have been trying the reset command for testing).
The current packet that I send is as follows
command = 0x05
data_length = 0x03
data[0] = 0x08
data[1] = 0x12
data[2] = 0x63
CRC = 0xFD90
I send the CRC as byte 1, then byte 0, just as the win_test sw does.
The data format is 1 start bit, 8 data bits, and 1 stop bit.
Baud rate 19200
I have looked at the signal (on a logic analyzer) from both the serial port on my computer, and the port I am using on the micropressor, and the actual data sent is the same. The difference is the delay between when one byte is sent and the next byte is sent. with the computer, there is a delay of 3 idle bits (156.25 uS) between each byte sent. I added a delay in my software to match this, and tried it again. I have not gotten any consistent results from the LCD yet. I have to send the reset command several times before it is recognozed, and sometimes it isn't recognized at all. I have also tried to send text command to the LCD with no luck. I am using the win_test software to verify that the CRC I generate is correct, and I know that is working properly.
My questions are:
1) How much delay is needed between each byte sent to the LCD?
2) Is there a way to use an SPI interface to a 633 instead of the RS232?
3) Does anyone have any experience with any of these serial LCD's and a microprocessor
4) The contrast on the LCD also needs to be turned up to an abnormally high level (100%)to display the text, and it still doesn't seem to show all of the pixels of the very top line at full brightness.
Thanks for any help ahead of time. I am using this LCD in a senior design project, and if I can't get it to work I will need to find another LCD (But we really like the features of this one)
The problem that I am having is that when I send data to the LCD, I receive no response. (I have been trying the reset command for testing).
The current packet that I send is as follows
command = 0x05
data_length = 0x03
data[0] = 0x08
data[1] = 0x12
data[2] = 0x63
CRC = 0xFD90
I send the CRC as byte 1, then byte 0, just as the win_test sw does.
The data format is 1 start bit, 8 data bits, and 1 stop bit.
Baud rate 19200
I have looked at the signal (on a logic analyzer) from both the serial port on my computer, and the port I am using on the micropressor, and the actual data sent is the same. The difference is the delay between when one byte is sent and the next byte is sent. with the computer, there is a delay of 3 idle bits (156.25 uS) between each byte sent. I added a delay in my software to match this, and tried it again. I have not gotten any consistent results from the LCD yet. I have to send the reset command several times before it is recognozed, and sometimes it isn't recognized at all. I have also tried to send text command to the LCD with no luck. I am using the win_test software to verify that the CRC I generate is correct, and I know that is working properly.
My questions are:
1) How much delay is needed between each byte sent to the LCD?
2) Is there a way to use an SPI interface to a 633 instead of the RS232?
3) Does anyone have any experience with any of these serial LCD's and a microprocessor
4) The contrast on the LCD also needs to be turned up to an abnormally high level (100%)to display the text, and it still doesn't seem to show all of the pixels of the very top line at full brightness.
Thanks for any help ahead of time. I am using this LCD in a senior design project, and if I can't get it to work I will need to find another LCD (But we really like the features of this one)
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