
During Stewart's talk last night, someone mentioned that Epson receipt printer had too small buffer and had to time print jobs to avoid losing data. There are 2 ways to get printer BUSY status: 1. You can query the printer for "online/offline" status by sending DLE EOT 1 (0x10 0x04 0x01) and it will return 1 byte. If bit 3 (0x08) is - 1 -- it is "offline" - 0 -- it is "online" 2. You can turn on ASB (automatic status back), where printer will send 4 bytes status back to you whenever status changes, such as pressing FEED button, buffer full, paper out, etc. To turn on "online/offline" status reporting, send GS a 2 (0x1d 0x61 0x02). To turn off "online/offline" status reporting, send GS a 0 (0x1d 0x61 0x00). From the 4 bytes returned, if bit 3 (0x08) of first byte is - 1 -- it is "offline" - 0 -- it is "online" -- William