upd7810: Fixed ADC output register range.
upd7810: ADC functions should return bytes.
upd7810: sample and hold ADC value at start of conversion process.
upd7810: clear sample and hold on ADC reset
Rename dummy_centronics to dmcntr (< 8 chars)
upd7810: remove code duplication in timers 0 and 1
upd7810: remove code duplication in ETIMER
upd7810: set ETIMER interrupts
Improve Epson ActionPrinter2000