Question

I am trying to print a message to a Bluetooth connected printer via SPP R200 protocol though my Android phone. I have paired, connected with the device. But the language the printer speaks is not the regular strings.

As far as I understand, the SPP R200 is a standard format but scary format as I feel it.

Because it is a standard format, is any standard routine / function/ method known that will convert the normal Java string to the spp r200 format? Any open source implementation or sample codes are welcome.

Thanks for the stackoverflow community in advance because I know somebody is always there to help here.

Answer 1

all you need is read manual and then send byte arrays not string to printer

fx. Printing code bar(CODE39, text: “aa1234”):

{GS,   len("aa1234"), 4/* CODE39*/, (byte)'a', (byte)'a', (byte)'1', (byte)'2', (byte)'3', (byte)'4', 0/*NUL*/}

{0x1d, 0x06,          0x04,          0x61,      0x61,      0x31,      0x32,      0x33,      0x34,     0x00}

for getting bytes from string use:

"my string".getBytes("ISO-8859-1");