APS EPM205-MRS, Техническое описание

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EPM205-MRS - Technical reference - Preliminary Page 24
Advanced Printing Systems
GS B n
Description: Serial communication and mode settings
Format:
<1Dh> <42h> <n>
Comments: Sets serial communication speed and mode
Bit 7: B7=0: Xon-Xoff mode (software control), B7=1: DSR/DTR mode (hardware
control)
Bit 6: Not used
Bit 5: Stopbit; B5=0, 1 stopbit; B5=1, 2 stopbits.
Bit 4: Not used
Bit 3: Not used
Bit 2, 1, 0: Speed:
n Communication speed (Bauds)
0 1 200
1 2 400
2 4 800
3 9 600
4 19 200
5 38 400
6 57 200
7 115 200
(Default n=83h: DSR/DTR; Normal mode, 1 Stopbit, 9600 Bds, No Parity)
GS b n
Description: Parallel port busy line hold time setting
Format:
<1Dh> <62h> <n>
Comments: Sets the minimum tBUSY hold time on the parallel busy line. See "Compatibility mode
timing" (refer to section 5.6.1) for an example of the waveform.
The ‘n’ value may be changed to avoid erratic character reception from the host’s
automatic character repeat
feature. This command repeats sending the latest byte sent when
the printer hold time tBUSY is too short (from 20µs to 100µs depending on the host’s
parallel port firmware). To avoid the repeating, the minimum time of tBUSY must be
increased. Please note that increasing the tBUSY hold time will reduce the communication
speed.
If the host firmware correctly controls the timing per the waveforms given in
"Compatibility mode timing" (see section 5.6.1) and has no automatic repeat feature, n can
equal 0, thereby minimizing time of tBUSY (around 25µs) and maximizing
communication speed.
By default n = 50 which gives 80µs for the minimum duration of tBUSY.
The time is given by the formula: (n * 1µs) + 30µs. (n from 00h to FFh).