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1 Turn off the power of the printer. - Van Mechelen

1 Turn off the power of the printer. - Van Mechelen

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10) When more data is to be received from <strong>the</strong> <strong>printer</strong>, <strong>the</strong> host chooses one <strong>of</strong><br />

three status selections:<br />

1. Setting HostBusy (nAutoFd) to Low and indicating that <strong>the</strong> host is ready to<br />

receive.<br />

2. Remaining in <strong>the</strong> Host Busy Data Available phase.<br />

3. Performing Termination and returning to <strong>the</strong> Compatibility mode.<br />

13.2.5 Device ID<br />

The device ID is a character string that provides <strong>the</strong> ID, <strong>the</strong> type, and o<strong>the</strong>r<br />

information regarding <strong>the</strong> <strong>printer</strong> connected to <strong>the</strong> interface. When <strong>the</strong> <strong>printer</strong><br />

receives a request for a device ID from <strong>the</strong> host, it replies with <strong>the</strong> following device<br />

ID:<br />

H H<br />

MFG : CBM ;<br />

CMD : ESC / POS ;<br />

MDL : CBM1000 ;<br />

CLS : PRINTER ;<br />

The first two bytes <strong>of</strong> <strong>the</strong> device ID indicate <strong>the</strong> length <strong>of</strong> <strong>the</strong> entire device ID<br />

(Including <strong>the</strong> first two bytes <strong>the</strong>mselves). For a description <strong>of</strong> a request for a<br />

device ID, refer to <strong>the</strong> “Negotiation” section earlier in <strong>the</strong> present Appendix.<br />

When <strong>the</strong> host receives <strong>the</strong> device ID string <strong>of</strong> <strong>the</strong> length indicated by <strong>the</strong> first two<br />

bytes, it must do so consecutively, without terminating <strong>the</strong> process until <strong>the</strong> entire<br />

device ID is received. If <strong>the</strong> process is terminated halfway, <strong>the</strong> <strong>printer</strong> discards <strong>the</strong><br />

rest <strong>of</strong> <strong>the</strong> string; when <strong>the</strong> <strong>printer</strong> receives a new request for <strong>the</strong> device ID, it<br />

sends <strong>the</strong> device ID beginning from <strong>the</strong> first character <strong>of</strong> <strong>the</strong> ID. After receiving <strong>the</strong><br />

ID <strong>of</strong> <strong>the</strong> length indicated by <strong>the</strong> first two bytes, <strong>the</strong> host must carry out <strong>the</strong><br />

termination even if <strong>the</strong> <strong>printer</strong> has data to send (Data Available). If <strong>the</strong> host does<br />

not carry out Termination and tries to receive data, <strong>the</strong> <strong>printer</strong> sends <strong>the</strong> <strong>printer</strong><br />

status.<br />

13.2.6 Termination<br />

Termination is <strong>the</strong> process <strong>of</strong> returning to Compatibility mode from <strong>the</strong> Nibble or<br />

Byte modes. When performing Termination, <strong>the</strong> host sets <strong>the</strong> signals as follows:<br />

• IEEE 1284 Active (nSelectln): Low<br />

• HostBusy (nAutoFd): High (Event 22)<br />

There are two methods <strong>of</strong> Termination:<br />

(1) Termination through a handshake between <strong>the</strong> host and <strong>the</strong> <strong>printer</strong>.<br />

(2) Immediate termination.<br />

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