GLK19264-7T-1U-WB-USB Matrix Orbital, GLK19264-7T-1U-WB-USB Datasheet - Page 19

• Manufacturer Part Number: GLK19264-7T-1U-WB-USB
• Description: LCD Character Display Modules Blue Background White Text
• Manufacturer: Matrix Orbital

Specifications of GLK19264-7T-1U-WB-USB

• Character Count X Line: 32 x 8
• Background Color: Blue
• Voltage Rating: + 5 VDC
• Operating Temperature Range: - 20 C to + 70 C
• Backlight Type: LED White
• Interface: USB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

4 Communications
4.1 Introduction
4.1.1 I
on a single I
pull up resistors, with a nominal value of 1K to 10K, are placed on the SCL and SDA communication lines
coming from pins two and three of the Data / Power Connector respectively. Data responses by the module
are automatically output via RS232, in case the host will be querying the module, it is necessary for the host
to inform the module that its responses are to be output via I
254 /160 / 0 to turn off auto transmission of data in RS232. This will keep the data in the buffer until the
master clocks a read of the slave. The I
GLK19264-7T-1U uses 8-bit addressing, with the 8th or Least Significant Bit (LSB) bit designated as the
read/write bit, a 0 designates a write address and a 1 designates a read address. The default read address of
the display module will be 0x51, whereas the write address is 0x50 by default. This address may be changed
by using cmd 254 / 51 / <address>. The GLK19264-7T-1U should only be sent addresses that are even (LSB
is 0). When the I
the LSB has to be 0 for an I
effective address is $51 (0101 0001), since the LSB has to be 1 for an I
describe this Phillips I
addressed. When writing to the display module, the display will respond with a ACK when the write has
successfully been completed. However if the buffer has been filled, or the module is too busy processing
data it will respond with a NAK. When performing a multiple byte read within one I
byte read from the slave should be followed by an ACK to indicate that the master still needs data, and a
NAK to indicate that the transmission is over.
considerations when writing I
sent (only needs to be sent once, so this can be done somewhere in init): 254 / 160 / 0 this command puts
the reply data in the I
output buffer, query commands that reply with more than 16 bytes cannot be read (eg cmd Get FileSystem
Directory)
Matrix Orbital
The commands listed in this chapter describe how to configure data flow on the GLK19264-7T-1U.
The GLK19264-7T-1U is capable of communicating at 100 KHz in I
If we take a standard Phillips 7 bit address of $45 (100 0101), Matrix Orbital’s GLK19264-7T-1U would
The unit does not respond to general call address ($00).
When communicating in I
The GLK19264-7T-1U has some speed limitations, especially when run in I
* to be able to read the replies of query commands (eg. cmds 54, 55) the following command must be
* 3ms delay between the read commands
* 625us delay in between data bytes within a transaction is necessary
* 375us between transactions is necessary
2
C Communication Summary
2
C communication line. However, in order to communicate via I
2
C master wishes to write to the display, the effective address is $50 (0101 0000) , since
2
2
C output buffer instead of the RS232 output buffer. Please note that due to a 16 byte
C address as $8A (1000 1010). The read address would be $8B (1000 1011).
2
C master write. When the I
2
C code:
2
C the GLK19264-7T-1U will send an ACK on the 9th clock cycle when
2
C data lines operate at 5V normally or 3.3V for -1U style units. The
GLK19264-7T-1U
2
C master wishes to read the GLK19264-7T-1U, the
2
C. This can be done by sending command
2
2
C master read.
C mode, with 127 units addressable
2
C you must first ensure that
2
C mode. Here are some
2
C transaction, each
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