The serial port is 3 wire or 2 wire?
A: Our serial model has a total of 4 connections, including 3 data signals and 1 GND.
When using software flow control, it can only connect 2, 3, 5 three-wire, that is, connect TXD, RXD, GND
When hardware flow control is used, only 3, 4, and 5 wires can be connected, That is RXD, BUSY, GND
When no flow control is used, it can only connect 3, 5 two-wire, E.g connect RXD, GND
２．Q: I bought a RD-DH32 printer. The back is 5 wire interface. I connect the line in the following way. The printer's pin 2 is connected to R232 13-pin R1 IN on the MCU board. The printer's pin 3 is connected to the R232 14 pin T1 OUT on the microcontroller board. The printer's pin 5 is connected to the GND on the microcontroller board. After writing a good one-chip computer program, I debug with the one-chip computer serial port debugging tool, the computer can receive the content that the one-chip computer sends and prints. But with the single-chip board debugging, the printer does not print. What's the problem?
A: There may be a problem with the data you sent. You can try the following: 31 32 33 34 35 36 0D
The correct printer should type "123456". It Can also use a computer to connect the printer, use the serial port tool to send the above data
３． Q: What chip of the USB interface for RD series printer used?
A: Serial port is PL2303; Parallel port is PL2305
４． Q: my
printer self-test show 9600,8,n, what does cts protocol1 mean?
A: Serial port, 9600 baud rate, 8 data bits, n indicates no parity, cts indicates hardware flow control, and protocol1 indicates protocol. Hardware flow control is: Judge if the status of the printer CTS signal pin to determine whether the printer is busy or free
５． Q:When Using WH
printer to print It is normal, Also print a line with A40-8 normally, 3 lines
can also be ok, But with printing more than 4 lines, the indicator light becomes bright and change "not busy"after
A: It because that the STB signal interference, lower when STB is bright, But normal when sending pulses
６．Q:Does the RD-V80 Model Printer use Bluetooth Module For USB Interface or serial Bluetooth module BF10-H for UART interface?A: Serial Bluetooth module BF10-H for UART interface?
７． Q: What is the Bluetooth default device name? What should the pass code be filled in?
A: Device Name:RDV32BL,Pass code:0000
A: When busy, put a code of 13 (only once) and only send a code of 11 (only once) when it is idle. The user system can only interrupt the method to get such data, otherwise it may be wrong. It is recommended to use signs to control: it is done by hardware and it is very accurate.
A: The 11M is calculated upon 9600 Baud Rate, But when changed to 20M,The Baud Rate need to be recalculated. If still use earlier frequency, So it is not working, The baud rate is calculated by the crystal oscillator
10． Q:For RD-EH32-V2 printer, There is no issue about the 57600 baud rate, but why not working when changed to be 115200 baud rate.
A: The buffer is full, but it is still sending data. The sending speed is greater than the printing speed, it will cause the buffer to be full, Now it need to determine whether the printer is busy, or delay sending
11． Q: What is the highest baud rate of the printer?A: As per The computer standard it is 115200, Max can be up to 460,800, and unless the special occasion, the highest baud rate should not exceed 115200
12． Q: I am
a technician from a software company, Is it possible that the software our
company developing compatible with your RD-V32 Bluetooth printer, Can you provide
the development document and interface case example based on WINCE5.0 ?
A: Our Bluetooth module virtualizes a serial port in your operating system, By which Serial port operated with .Open the serial port with software and send the data to the printer.
Q: When connect the micro printer with user control system, some are normal connection, some are not abnormal connection.
A: The data line from control board must connect with 10K Pull-down resistor.
Q: If DSP chip is 3.3V power supply, external device is 5v power supply, what match should It be of the two device.
A: By SN74LVC8T245 and other devices to complete the match, this chip can be level-shifted to Realize the mutual transfer between 3.3V and 5V.
15． Q: I Want to share a printer with several devices, can you solve it? (A system
consisting of a few lower-level instruments requires only one printer for this
system due to the size of the system. The lower-level instruments share this
A: Yes, but it cannot be printed on a machine at the same time, only by different time printing. Every instrument communicates with each other. Whoever wants to print, it is necessary to see if there is any other instrument assembly line, If printing, wait and if it is not printed, send the printing data. Check The 485 communications specifically, you can connect multiple devices together and communicate with each other
16. A: Yes, but it cannot be printed on a machine at the same time, only by different time printing. Every instrument communicates with each other. Whoever wants to print, it is necessary to see if there is any other instrument assembly line, If printing, wait and if it is not printed, send the printing data. Check The 485 communications specifically, you can connect multiple devices together and communicate with each other
A: No need judgment, the data can be printed by directly after sending data. It is possible to judge whether rx is 13h or 11h. The premise is: as long as your data is not more than 24K on the line. The printer has data buffers. If the printer's buffer is full, a 13 will be sent to you, the printer will continue to print a buffer and then send a 11 to you.
You can make a variable in the serial port interruption to determine whether the returned data is 13 or 11, and if it is equal to 13, it will not send the data mark. If it is equal to 11, it will not send the mark, and you can judge this mark before sending data each time.
You can judge without sending a byte. For example, if you send 256 bytes of data as a packet, you can judge it before sending each packet because the printer's buffer full mark is set to 1k. The data space is used as the reserved space sent by the packet.
When your system is configured, remember that the printer is free at power-up. Your first think that you can send data unless you receive 13 to stop sending data. The printer is passively receiving. Your system is sending it unsolicited. Don't wait until the printer returns to data 11. After you send the data, wait 13 in the interrupt and receive the 13 marks.