11 s emiconductor , i nc. fea tures ? 5v operation ? pin to pin and functional compatible to 16c454 ? 16 byte transmit fifo ? 16 byte receive fifo with error flags ? modem control signals ( cts ? , r ts ? , dsr ? , dtr ? , ri ? , cd ? ) ? programmable character lengths (5, 6, 7, 8) ? even, odd, or no parity bit generation and detection ? status report register ? independent transmit and receive control ? ttl compatible inputs, outputs ? software compatible with 8250 and ei16c550 ? 460.8 khz transmit/receive operation with 7.372 mhz crystal or external clock source EI16C554 q u ad u ar t description the EI16C554 is universal asynchronous receiver and t ransmitter with 16 byte transmit and receive fifo. a programmable baud rate generator is provided to select transmit and receive clock rates from 50 hz to 1.5mhz. the EI16C554 is an improved version of the ei16c550 uar t with higher operating speed and lower access time. the EI16C554 on board status registers provides the error conditions, type and status of the transfer operation being performed. included is complete modem control capability , and a processor interrupt system that may be software tailored to the user ? s requirements. the EI16C554 provides internal loop- back capability for on board diagnostic testing. the EI16C554 is fabricated in an advanced cmos process to achieve low drain power and high speed requirements. pin configura tion 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 dsra ? ctsa ? dtra ? vcc r tsa ? int a csa ? txa iow ? txb csb ? intb r tsb ? gnd dtrb ctsd ? dsrb ? dsra* ctsa* dtra* vcc r tsa* int a csa* txa iow* txb csb* intb r tsb* gnd dtrb ctsd* dsrd ? ctsd ? dtrd ? gnd r tsd ? intd csd ? txd ior ? txc csc ? intc r tsc ? vcc dtrc ? ctsc ? dsrc ? dsrd* ctsd* dtrd* gnd r tsd* intd csd* txd ior* txc csc* intc r tsc* vcc dtrc* ctsc* cdb ? rib ? rxb ? vcc nc a2 a1 a0 xt al1 xt al2 erset rxrdy ? txrd ? gnd rxc ric ? cdc ? dsrb* cdb* rib* rxb* vcc a2 a1 a0 xt al1 xt al2 reset gnd rxc ric* cdc* dsrc* cda ? ria ? rxa gnd d7 d6 d5 d4 d3 d2 d1 d0 intsel vcc rxd rid ? cdo ? cda* ria* rxa gnd d7 d6 d5 d4 d3 d2 d1 d0 vcc rxd rid* cdd* 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 9 8 7 6 5 4 3 2 1 68 67 66 65 64 63 62 61 EI16C554 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 EI16C554 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 64-pin tqfp 68-pin plcc
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