PRN608-S

dot line so that the number does not exceed the specified maximum number of activated dots. The PRN608-S determines logical blocks each time it prints a single dot line.

In dynamic division, in order to avoid unclear printing, at the first step of the motor the thermal head is driven and at the second step the paper is fed.

Also, since the order of the printing blocks and printing speed are changed in each dot line according to the content of the print data, print quality may be lower than that in fixed division. If print quality is regarded as important, printing in fixed division is recommended.

The maximum number of activated dots in the initialisation status is specified using the function switches.

64 through 256 dots can, however, are set using the command for setting the number of dynamic division dots.

When the maximum number of activated dots is 128 dots, and all of the dots are driven, as shown in

2.7.3 Head Control Circuit

The PRN608-S has a function for measuring the resistance of the thermal head connected to the FTP608.

The PRN608-S measures the resistance of the thermal head and detects the errors at initialisation.

Based on the measurement, the PRN608-S determines how much energy to apply. No adjustment is needed for replacing the FTP608 to get the best printing.

2.7.4 Head temperature measurement circuit

The thermistor is mounted on the FTP608 to measure the temperature of the thermal head.

The PRN608-S determines the energy to be applied to the head and also checks for head temperature errors.

If the temperature of the thermal head is -10 °C or lower, or 80 °C or higher, the PRN608-S stops driving and puts the printer in head temperature error status. If the temperature of the thermal head is returned to from -5 °C to 75 °C, the printer goes to printable status.

2.7.5 Vhead interrupt circuit

This circuit interrupts Vhead to prevent electrolytic corrosion of the thermal head and to enable the detection of the resistance mentioned above.

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Fujitsu PRN608-S user manual 2-14