/* @(#)zsreg.h 1.1 86/02/03 SMI */ /* * Copyright (c) 1983 by Sun Microsystems, Inc. */ /* * Zilog 8530 SCC Serial Communications Controller * * This is a dual uart chip with on-chip baud rate generators. * It is about as brain-damaged as the typical modern uart chip, * but it does have a lot of features as well as the usual lot of * brain damage around addressing, write-onlyness, etc. */ /* * Uart registers: * * There are 16 write registers and 9 read registers in each channel. * As usual, the two channels are ALMOST orthogonal, not exactly. Most regs * can only be written to, or read, but not both. To access one, you must * first write to register 0 with the number of the register you * are interested in, then read/write the actual value, and hope that * nobody interrupts you in between. * * Note that the register&bit assignment is suspiciously like the Intel 8274. * Do you think they read each others' data sheets? Can they decode them? */ /* bits in RR0 */ #define ZSRR0_RX_READY 0x01 /* received character available */ #define ZSRR0_TIMER 0x02 /* if R15_TIMER, timer reached 0 */ #define ZSRR0_TX_READY 0x04 /* transmit buffer empty */ #define ZSRR0_CD 0x08 /* CD input (latched if R15_CD) */ #define ZSRR0_SYNC 0x10 /* SYNC input (latched if R15_SYNC) */ #define ZSRR0_CTS 0x20 /* CTS input (latched if R15_CTS) */ #define ZSRR0_TXUNDER 0x40 /* (SYNC) Xmitter underran */ #define ZSRR0_BREAK 0x80 /* received break detected */ /* bits in RR1 */ #define ZSRR1_ALL_SENT 0x01 /* all chars fully transmitted */ #define ZSRR1_PE 0x10 /* parity error (latched, must reset) */ #define ZSRR1_DO 0x20 /* data overrun (latched, must reset) */ #define ZSRR1_FE 0x40 /* framing/CRC error (not latched) */ #define ZSRR1_RXEOF 0x80 /* end of recv sdlc frame */ /* bits in R/WR2 -- interrupt vector number. */ /* NOTE that RR2 in channel A is unmodified, while in channel B it is modified by the current status of the UARTs. (This is independent of the setting of WR9_VIS.) If no interrupts are pending, the modified status is Channel B Special Receive. It can be written from either channel. */ /* bits in RR3 -- Interrupt Pending flags for both channels (this reg can only be read in Channel A, tho. Thanks guys.) */ #define ZSRR3_IP_B_STAT 0x01 /* Ext/status int pending, chan B */ #define ZSRR3_IP_B_TX 0x02 /* Transmit int pending, chan B */ #define ZSRR3_IP_B_RX 0x04 /* Receive int pending, chan B */ #define ZSRR3_IP_A_STAT 0x08 /* Ditto for channel A */ #define ZSRR3_IP_A_TX 0x10 #define ZSRR3_IP_A_RX 0x20 /* bits in RR8 -- this is the same as reading the Data port */ /* bits in RR10 -- DPLL and SDLC Loop Mode status -- not entered*/ /* bits in R/WR12 -- lower byte of time constant for baud rate generator */ /* * The following macro can be used to generate the baud rate generator's * time constants. The parameters are the input clock to the BRG (eg, * 5000000 for 5MHz) and the desired baud rate. This macro assumes that * the clock needed is 16x the desired baud rate. */ #define ZSTimeConst(InputClock, BaudRate) (( InputClock / (2*BaudRate*16)) - 2) /* bits in R/WR13 -- upper byte of time constant for baud rate generator */ /* bits in R/WR15 -- interrupt enables for status conditions */ #define ZSR15_TIMER 0x02 /* ie if baud rate generator = 0 */ #define ZSR15_CD 0x08 /* ie transition on CD (car. det.) */ #define ZSR15_SYNC 0x10 /* ie transition on SYNC (gen purp) */ #define ZSR15_CTS 0x20 /* ie transition on CTS (clr to send) */ #define ZSR15_TX_UNDER 0x40 /* (SYNC) ie transmit underrun */ #define ZSR15_BREAK 0x80 /* ie on start, and end, of break */ /* Write register 0 -- common commands and Register Pointers */ #define ZSWR0_REG 0x0F /* mask: next reg to read/write */ #define ZSWR0_RESET_STATUS 0x10 /* reset status bit latches */ #define ZSWR0_FIRST_RX 0x20 /* in WR1_RX_FIRST_IE, enab next int */ #define ZSWR0_RESET_TXINT 0x28 /* reset transmitter interrupt */ #define ZSWR0_RESET_ERRORS 0x30 /* reset read character errors */ #define ZSWR0_CLR_INTR 0x38 /* Reset Interrupt In Service */ #define ZSWR0_RESET_RXCRC 0x40 /* Reset Rx CRC generator. */ #define ZSWR0_RESET_TXCRC 0x80 /* Reset Tx CRC generator. */ #define ZSWR0_RESET_EOM 0xC0 /* Reset Tx underrun / EOM. */ /* bits in WR1 */ #define ZSWR1_SIE 0x01 /* status change master int enable */ /* Also see R15 for individual enabs */ #define ZSWR1_TIE 0x02 /* transmitter interrupt enable */ #define ZSWR1_PARITY_SPECIAL 0x04 /* parity err causes special rx int */ #define ZSWR1_RX_FIRST_IE 0x08 /* r.i.e. on 1st char of msg */ #define ZSWR1_RIE 0x10 /* receiver interrupt enable */ /* There are other Receive interrupt options defined, see data sheet. */ /* bits in WR2 are defined above as R/WR2. */ /* bits in WR3 */ #define ZSWR3_RX_ENABLE 0x01 /* receiver enable */ #define ZSWR3_RXCRC_ENABLE 0x08 /* receiver CRC enable */ #define ZSWR3_HUNT 0x10 /* enter hunt mode */ #define ZSWR3_AUTO_CD_CTS 0x20 /* auto-enable CD&CTS rcv&xmit ctl */ #define ZSWR3_RX_5 0x00 /* receive 5-bit characters */ #define ZSWR3_RX_6 0x80 /* receive 6 bit characters */ #define ZSWR3_RX_7 0x40 /* receive 7 bit characters */ #define ZSWR3_RX_8 0xC0 /* receive 8 bit characters */ /* bits in WR4 */ #define ZSWR4_PARITY_ENABLE 0x01 /* Gen/check parity bit */ #define ZSWR4_PARITY_EVEN 0x02 /* Gen/check even parity */ #define ZSWR4_1_STOP 0x04 /* 1 stop bit */ #define ZSWR4_1_5_STOP 0x08 /* 1.5 stop bits */ #define ZSWR4_2_STOP 0x0C /* 2 stop bits */ #define ZSWR4_SDLC 0x20 /* SDLC mode */ #define ZSWR4_X1_CLK 0x00 /* clock is 1x */ #define ZSWR4_X16_CLK 0x40 /* clock is 16x */ #define ZSWR4_X32_CLK 0x80 /* clock is 32x */ #define ZSWR4_X64_CLK 0xC0 /* clock is 64x */ /* bits in WR5 */ #define ZSWR5_TXCRC_ENABLE 0x01 /* transmitter CRC enable */ #define ZSWR5_RTS 0x02 /* RTS output */ #define ZSWR5_TX_ENABLE 0x08 /* transmitter enable */ #define ZSWR5_BREAK 0x10 /* send break continuously */ #define ZSWR5_TX_5 0x00 /* transmit 5 bit chars or less */ #define ZSWR5_TX_6 0x40 /* transmit 6 bit characters */ #define ZSWR5_TX_7 0x20 /* transmit 7 bit characters */ #define ZSWR5_TX_8 0x60 /* transmit 8 bit characters */ #define ZSWR5_DTR 0x80 /* DTR output */ /* bits in WR6 -- Sync characters or SDLC address field. */ /* bits in WR7 -- Sync character or SDLC flag */ /* bits in WR8 -- transmit buffer. Same as writing to data port. */ /* bits in WR9 -- Master interrupt control and reset. Accessible thru either channel, there's only one of them. */ #define ZSWR9_VECTOR_INCL_STAT 0x01 /* Include status bits in int vector */ #define ZSWR9_NO_VECTOR 0x02 /* Do not respond to int ack cycles */ #define ZSWR9_DIS_LOWER_CHAIN 0x04 /* Disable ints lower in daisy chain */ #define ZSWR9_MASTER_IE 0x08 /* Master interrupt enable */ #define ZSWR9_STAT_HIGH 0x10 /* Modify ivec bits 6-4, not 1-3 */ #define ZSWR9_RESET_CHAN_B 0x40 /* Reset just channel B */ #define ZSWR9_RESET_CHAN_A 0x80 /* Reset just channel A */ #define ZSWR9_RESET_WORLD 0xC0 /* Force hardware reset */ /* bits in WR10 -- SDLC, NRZI, FM control bits */ #define ZSWR10_UNDERRUN_ABORT 0x04 /* send abort on TX underrun */ #define ZSWR10_PRESET_ONES 0x80 /* preset CRC to ones (SDLC) */ /* bits in WR11 -- clock mode control */ #define ZSWR11_TRXC_XTAL 0x00 /* TRxC output = xtal osc */ #define ZSWR11_TRXC_XMIT 0x01 /* TRxC output = xmitter clk */ #define ZSWR11_TRXC_BAUD 0x02 /* TRxC output = baud rate gen */ #define ZSWR11_TRXC_DPLL 0x03 /* TRxC output = Phase Locked Loop */ #define ZSWR11_TRXC_OUT_ENA 0x04 /* TRxC output enable (unless input) */ #define ZSWR11_TXCLK_RTXC 0x00 /* Tx clock is RTxC pin */ #define ZSWR11_TXCLK_TRXC 0x08 /* Tx clock is TRxC pin */ #define ZSWR11_TXCLK_BAUD 0x10 /* Tx clock is baud rate gen output */ #define ZSWR11_TXCLK_DPLL 0x18 /* Tx clock is Phase Locked Loop o/p */ #define ZSWR11_RXCLK_RTXC 0x00 /* Rx clock is RTxC pin */ #define ZSWR11_RXCLK_TRXC 0x20 /* Rx clock is TRxC pin */ #define ZSWR11_RXCLK_BAUD 0x40 /* Rx clock is baud rate gen output */ #define ZSWR11_RXCLK_DPLL 0x60 /* Rx clock is Phase Locked Loop o/p */ #define ZSWR11_RTXC_XTAL 0x80 /* RTxC uses crystal, not TTL signal */ /* bits in WR12 -- described above as R/WR12 */ /* bits in WR13 -- described above as R/WR13 */ /* bits in WR14 -- misc control bits, and DPLL control */ #define ZSWR14_BAUD_ENA 0x01 /* enables baud rate counter */ #define ZSWR14_BAUD_FROM_PCLK 0x02 /* Baud rate gen src = PCLK not RTxC */ #define ZSWR14_DTR_IS_REQUEST 0x04 /* Changes DTR line to DMA Request */ #define ZSWR14_AUTO_ECHO 0x08 /* Echoes RXD to TXD */ #define ZSWR14_LOCAL_LOOPBACK 0x10 /* Echoes TX to RX in chip */ #define ZSWR14_DPLL_NOP 0x00 /* These 8 commands are mut. exclu. */ #define ZSWR14_DPLL_SEARCH 0x20 /* Enter search mode in DPLL */ #define ZSWR14_DPLL_RESET 0x40 /* Reset missing clock in DPLL */ #define ZSWR14_DPLL_DISABLE 0x60 /* Disable DPLL */ #define ZSWR14_DPLL_SRC_BAUD 0x80 /* Source for DPLL is baud rate gen */ #define ZSWR14_DPLL_SRC_RTXC 0xA0 /* Source for DPLL is RTxC pin */ #define ZSWR14_DPLL_FM 0xC0 /* DPLL should run in FM mode */ #define ZSWR14_DPLL_NRZI 0xE0 /* DPLL should run in NRZI mode */ /* bits in WR15 -- described above as R/WR15 */ /* * UART register addressing * * It would be nice if they used 4 address pins to address 15 registers, * but they only used 1. So you have to write to the control port then * read or write it; the 2nd cycle is done to whatever register number * you wrote in the first cycle. * * The data register can also be accessed as Read/Write register 8. */ #ifndef LOCORE struct zscc_device { unsigned char zscc_control; unsigned char :8; /* Filler */ unsigned char zscc_data; unsigned char :8; /* Filler */ }; #endif