Hi everyone,
I am using a LM3S5951 controllers for one of my projects in which I need to implement a host side driver for Dot Matrix printer .
I am done with enumeration of the printer, but now I would like to know how can I send data to printers using bulk transfers. I am using the Stellaries USB Library for the same where I found some host side codes for keyboard and pendrive. I would like to know, how to go about this.
Regards
Dhanush
A) Before starting firmware coding, you have to examine the printer on a PC, to know the printer protocols better.
1) Read out these information from the printer, using USB sniffer on the PC. - Device and Configuration descriptor set. The descriptor set is used to check if your firmware reads them out correctly or not.
- Printer’s Device ID string In the enumeration, PC reads out Device ID string using GET_DEVICE_ID request (control transfer), of this SETUP packet layout.
bmRequestType: 0xA1 bRequest : 0x00 (GET_DEVICE_ID) wValue : 0x01 (config index) wIndex : 0x00 (Interface / Alternate) wLength : length of ID string
Here is the Device ID string of an old laser printer (EPSON LP-2400) on my desktop.
00 6B 4D 46 47 3A 45 50 53 4F 4E 3B 43 4D 44 3A .kMFG:EPSON;CMD: 45 4A 4C 2C 45 53 43 50 32 34 4A 2D 38 34 2C 45 EJL,ESCP24J-84,E 53 43 50 41 47 45 4A 2D 30 34 2C 45 53 43 50 53 SCPAGEJ-04,ESCPS 55 50 45 52 2D 30 30 2C 50 52 32 30 31 2D 30 30 UPER-00,PR201-00 3B 4D 44 4C 3A 4C 50 2D 32 34 30 30 3B 43 4C 53 ;MDL:LP-2400;CLS 3A 50 52 49 4E 54 45 52 3B 44 45 53 3A 45 50 53 :PRINTER;DES:EPS 4F 4E 20 4C 50 2D 32 34 30 30 3B ON LP-2400;
"CMD:" tag on the Device ID string shows the PDL (Page Description Language), applied to print data. In above example,
CMD:EJL,ESCP24J-84,ESCPAGEJ-04,ESCPSUPER-00,PR201-00;
This printer supports Epson ESC/P and PC-PR201 enumeration. You may use these sniffers on Windows, USBlyzer (commercial, 33 days trial) http://www.usblyzer.com/ USBTrace (commercial, 15 days trial) http://www.sysnucleus.com/
To read out device/config descriptors and Device ID string, the enumeration sequence of the printer is traced. To catch enumeration on USBlyzer, you'll need to enable "Capture menu -> Capture Hot-plugged" before plugging in the target printer to the PC.
2) Make a "test page" data on the PC - First of all, your PC should be installed the correct driver of the printer. - Make a "test page" on a text editor, like WordPad, as close to your required page layout as possible. - Print the page on the printer from the PC, tuning the page layout until you are satisfied. - When the page finishes, switch to "Print to File"
On Windows7, bottom Start button > Device and printers > right click on the target printer > Printer’s properties > Ports tab forums.techguy.org...er-properties-port.jpg Check "FILE: Print to File"
And then, print the "test page" on the editor. Now that you have "test page" data on a file.
To be continued..
Tsuneo
Hi Tsuneo,
I successfully intterfaced the dot matrix printer using the details provided by you for LM3S5951 controller. I am using an epson LX-300 printer which supports esc/p2 pdl. now when eveytime I send data to printer preceded by an init printer command , the printer prints data. But now when I send data w/o init printer command it prints data once in every two tries. Please provide some solution.
Regards Sanket K
Answered to Dhanush in TI Stellaris forum, e2e.ti.com/.../1172109.aspx
Sanket, ESC/P line printer prints data on its buffer to paper, when it receives LF (0x0A). On your code, you may terminate a string with LF, like "ABCD\n"
Now that I have successfully interfaced the printer using USB, everything is working fine. I would also like to check whether the printer is busy or not like it has been checked using the 25 pin centronics using LPT. How could I achieve this I have one IN endpoint for the printer.
Regards Dhanush
> I have one IN endpoint for the printer.
The bulk IN endpoint of the printer interface is optional. It’s role is specific to each printer model. Unfortunately, Epson doesn’t open the information of the role (protocol) over the bulk IN. You may get some printer status, or nothing. Try it.
ulBytes = USBHCDPipeRead( g_USBHPRNDevice.ulBulkInPipe, pBuffer, sizeof(pBuffer) );
> I would also like to check whether the printer is busy or not like it has been checked using the 25 pin centronics using LPT.
NAK on the bulk OUT endpoint corresponds to the BUSY signal of Centronics.
While the endpoint is NAKing, USBHCDPipeWrite() (and USBHCDPipeRead()) blocks the caller thread. I believe this is the reason why you need "BUSY" signal.
Instead of these blocking calls, you may apply non-blocking USBHCDPipeSchedule() to start transfer over the bulk IN or OUT endpoint.
USBHCDPipeSchedule( g_USBHPRNDevice.ulBulkOutPipe, pBuffer, sizeof(pBuffer) ); or USBHCDPipeSchedule( g_USBHPRNDevice.ulBulkInPipe, pBuffer, sizeof(pBuffer) );
When the transfer finishes, callback is called for each endpoint. This callback is registered at USBHCDPipeAllocSize() in your USBHPRNOpen()
static void PRNEndpointCallback(uint32_t ui32Pipe, uint32_t ui32Event); static void * USBHPRNOpen(tUSBHostDevice *pDevice) { ... ... g_sUSBHMSCDevice.ui32BulkInPipe = USBHCDPipeAllocSize(0, USBHCD_PIPE_BULK_IN_DMA, psDevice, psEndpointDescriptor->wMaxPacketSize, PRNEndpointCallback); // <------- ... ... g_sUSBHMSCDevice.ui32BulkOutPipe = USBHCDPipeAllocSize(0, USBHCD_PIPE_BULK_OUT_DMA, psDevice, psEndpointDescriptor->wMaxPacketSize, PRNEndpointCallback); // <-------
In the callback,
static void PRNEndpointCallback(uint32_t ui32Pipe, uint32_t ui32Event) { switch ( ui32Event ) { case USB_EVENT_TX_COMPLETE: // transfer on OUT endpoint finishes // // notify to the main thread by a flag, or start another transfer // break; case USB_EVENT_RX_AVAILABLE: // transfer on IN endpoint finishes // read out data into a buffer USBHCDPipeReadNonBlocking( g_USBHPRNDevice.ulBulkInPipe, pBuffer, sizeof(pBuffer) ); break; default: break; } }
Hi Tsuneo ,
I wish to interface a Laser printer (high USB speed device) to my ARM controller.But TIVA supports only low speed and full-speed devices . Is there any solution .Is there any interfacing circuitry ???
Regards, Sanket
> But TIVA supports only low speed and full-speed devices .
Surely USB host on Tiva TM4C123x supports just low-/full-speed. But TM4C129x does high-speed, too, with an external ULPI PHY chip. Unfortunately, TivaWare doesn't implement external PHY chip, yet.
> I wish to interface a Laser printer (high USB speed device) to my ARM controller.
You may consider on other MCUs.
a) STM32F2/F4 with an external ULPI PHY chip The low-cost pair, STM32F4 Discovery board and "USB3300 USB HS Board", is handy to play high-speed USB. www.wvshare.com/.../USB3300-USB-HS-Board.htm
ST's STM32_USB-Host-Device_Lib_V2.1.0 doesn't have printer host. But you may write it, based on Mass-Storage host example In this link, we discussed on modification for CDC/RNDIS host. Similar modification is applied to printer host. my.st.com/.../DispForm.aspx
b) LPC18xx/LPC43xx (with on-chip high-speed PHY) - USB host library in LPCOpen supports printer host, but no example. You may write it fairly easily, based on HID keyboard host example. www.lpcware.com/.../lpcopen-software-development-platform-lpc18xx-packages-0
c) Raspberry PI and BeagleBone Black Raspbian / Angstrom Linux supports printer host.
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