X-Git-Url: https://git.friedersdorff.com/?a=blobdiff_plain;ds=sidebyside;f=tmk_core%2Fprotocol%2Fibmpc.c;h=5f2ca79b2fba9f1bd8067b46ed1d2ca8ca6044a1;hb=12e5a3a13eb86852ad58c131e28ba29c5f09bb2d;hp=374e7fa4b7341e2308aa827607526aeec240dcba;hpb=4588ae8dacea53384827351f4460ffe62f111ea0;p=max%2Ftmk_keyboard.git diff --git a/tmk_core/protocol/ibmpc.c b/tmk_core/protocol/ibmpc.c index 374e7fa4..5f2ca79b 100644 --- a/tmk_core/protocol/ibmpc.c +++ b/tmk_core/protocol/ibmpc.c @@ -56,19 +56,22 @@ POSSIBILITY OF SUCH DAMAGE. } while (0) -volatile uint8_t ibmpc_protocol = IBMPC_PROTOCOL_AT; +volatile uint16_t ibmpc_isr_debug = 0; +volatile uint8_t ibmpc_protocol = IBMPC_PROTOCOL_NO; volatile uint8_t ibmpc_error = IBMPC_ERR_NONE; -/* 2-byte buffer for data received from keyhboard +/* 2-byte buffer for data received from keyboard * buffer states: * FFFF: empty * FFss: one data - * sstt: two data(full) - * 0xFF can not be stored as data in buffer because it means empty or no data. + * sstt: two data + * eeFF: error + * where ss, tt and ee are 0x00-0xFE. 0xFF means empty or no data in buffer. */ static volatile uint16_t recv_data = 0xFFFF; /* internal state of receiving data */ -static volatile uint16_t isr_data = 0x8000; +static volatile uint16_t isr_state = 0x8000; +static uint8_t timer_start = 0; void ibmpc_host_init(void) { @@ -96,20 +99,19 @@ int16_t ibmpc_host_send(uint8_t data) bool parity = true; ibmpc_error = IBMPC_ERR_NONE; - if (ibmpc_protocol == IBMPC_PROTOCOL_XT) return -1; - dprintf("w%02X ", data); IBMPC_INT_OFF(); /* terminate a transmission if we have */ inhibit(); - wait_us(100); // 100us [4]p.13, [5]p.50 + wait_us(100); // [5]p.54 /* 'Request to Send' and Start bit */ data_lo(); - clock_hi(); - WAIT(clock_lo, 10000, 1); // 10ms [5]p.50 + wait_us(100); + clock_hi(); // [5]p.54 [clock low]>100us [5]p.50 + WAIT(clock_lo, 10000, 1); // [5]p.53, -10ms [5]p.50 /* Data bit[2-9] */ for (uint8_t i = 0; i < 8; i++) { @@ -133,14 +135,15 @@ int16_t ibmpc_host_send(uint8_t data) /* Stop bit */ wait_us(15); data_hi(); + WAIT(clock_hi, 50, 6); + WAIT(clock_lo, 50, 7); /* Ack */ - WAIT(data_lo, 50, 6); - WAIT(clock_lo, 50, 7); + WAIT(data_lo, 50, 8); /* wait for idle state */ - WAIT(clock_hi, 50, 8); - WAIT(data_hi, 50, 9); + WAIT(clock_hi, 50, 9); + WAIT(data_hi, 50, 10); // clear buffer to get response correctly recv_data = 0xFFFF; @@ -166,19 +169,50 @@ int16_t ibmpc_host_recv(void) ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { data = recv_data; - if ((data&0xFF00) != 0xFF00) { // recv_data:sstt -> recv_data:FFtt, ret:ss - ret = (data>>8)&0x00FF; - recv_data = data | 0xFF00; - } else if (data != 0xFFFF) { // recv_data:FFss -> recv_data:FFFF, ret:ss - ret = data&0x00FF; - recv_data = data | 0x00FF; - } + + // remove data from buffer: + // FFFF(empty) -> FFFF + // FFss(one data) -> FFFF + // sstt(two data) -> FFtt + // eeFF(errror) -> FFFF + recv_data = data | (((data&0xFF00) == 0xFF00) ? 0x00FF : 0xFF00); } - if (ret != 0xFF) dprintf("r%02X ", ret); - if (recv_data != 0xFFFF) dprintf("b%04X ", recv_data); - return ((ret != 0xFF) ? ret : -1); + if ((data&0x00FF) == 0x00FF) { + // error: eeFF + switch (data>>8) { + case IBMPC_ERR_FF: + // 0xFF(Overrun/Error) from keyboard + dprintf("!FF! "); + ret = 0xFF; + break; + case IBMPC_ERR_FULL: + // buffer full + dprintf("!FULL! "); + ret = 0xFF; + break; + case 0xFF: + // empty: FFFF + return -1; + default: + // other errors + dprintf("e%02X ", data>>8); + return -1; + } + } else { + if ((data | 0x00FF) != 0xFFFF) { + // two data: sstt + dprintf("b:%04X ", data); + ret = (data>>8); + } else { + // one data: FFss + ret = (data&0x00FF); + } + } + //dprintf("i%04X ", ibmpc_isr_debug); ibmpc_isr_debug = 0; + dprintf("r%02X ", ret); + return ret; } int16_t ibmpc_host_recv_response(void) @@ -194,10 +228,15 @@ int16_t ibmpc_host_recv_response(void) void ibmpc_host_isr_clear(void) { - isr_data = 0x8000; + ibmpc_isr_debug = 0; + ibmpc_protocol = 0; + ibmpc_error = 0; + isr_state = 0x8000; recv_data = 0xFFFF; } +#define LO8(w) (*((uint8_t *)&(w))) +#define HI8(w) (*(((uint8_t *)&(w))+1)) // NOTE: With this ISR data line can be read within 2us after clock falling edge. // To read data line early as possible: // write naked ISR with asembly code to read the line and call C func to do other job? @@ -205,68 +244,112 @@ ISR(IBMPC_INT_VECT) { uint8_t dbit; dbit = IBMPC_DATA_PIN&(1<>1; - if (dbit) isr_data |= 0x8000; - - // isr_data: state of receiving data from keyboard - // 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 - // ----------------------------------------------------- - // Initial: *1 0 0 0 0 0 0 0 | 0 0 0 0 0 0 0 0 MSB sentinel - // XT IBM: b7 b6 b5 b4 b3 b2 b1 b0 | s1 s0 *1 0 0 0 0 0 after receiving ** - // XT Clone: b7 b6 b5 b4 b3 b2 b1 b0 | s1 *1 0 0 0 0 0 0 after receiving - // AT: st pr b7 b6 b5 b4 b3 b2 | b1 b0 s0 *1 0 0 0 0 after receiving - // AT**: pr b7 b6 b5 b4 b3 b2 b1 | b0 s0 *1 0 0 0 0 0 before stop bit ** + + // Timeout check + uint8_t t; + // use only the least byte of millisecond timer + asm("lds %0, %1" : "=r" (t) : "p" (&timer_count)); + //t = (uint8_t)timer_count; // compiler uses four registers instead of one + if (isr_state == 0x8000) { + timer_start = t; + } else { + // This gives 2.0ms at least before timeout + if ((uint8_t)(t - timer_start) >= 3) { + ibmpc_isr_debug = isr_state; + ibmpc_error = IBMPC_ERR_TIMEOUT; + goto ERROR; + + // timeout error recovery - start receiving new data + // it seems to work somehow but may not under unstable situation + //timer_start = t; + //isr_state = 0x8000; + } + } + + isr_state = isr_state>>1; + if (dbit) isr_state |= 0x8000; + + // isr_state: state of receiving data from keyboard // - // x x x x x x x x | 0 0 0 0 0 0 0 0 midway(0-7 bits received) - // x x x x x x x x | 1 0 0 0 0 0 0 0 midway(8 bits received) - // x x x x x x x x | 0 1 0 0 0 0 0 0 XT IBM-midway or AT-midway - // x x x x x x x x | 1 1 0 0 0 0 0 0 XT Clone-done - // x x x x x x x x | 0 0 1 0 0 0 0 0 AT-midway - // x x x x x x x x | 1 0 1 0 0 0 0 0 XT IBM-done or AT-midway ** - // x x x x x x x x | x 1 1 0 0 0 0 0 illegal - // x x x x x x x x | x x 0 1 0 0 0 0 AT-done - // x x x x x x x x | x x 1 1 0 0 0 0 illegal - // other states than avobe illegal + // This should be initialized with 0x8000 before receiving data and + // the MSB '*1' works as marker to discrimitate between protocols. + // It stores sampled bit at MSB after right shift on each clock falling edge. // - // **: AT can take same as end sate of XT IBM(1010 000) when b0 is 1, - // to discriminate between them we will have to wait a while for stop bit. + // XT protocol has two variants of signaling; XT_IBM and XT_Clone. + // XT_IBM uses two start bits 0 and 1 while XT_Clone uses just start bit 1. + // https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-XT-Keyboard-Protocol // - // mask for isr_data: - // 0x00A0(1010 0000) when XT IBM - // 0x00C0(1100 0000) when XT Clone - // 0x0010(xx01 0000) when AT + // 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 + // ----------------------------------------------------- + // *1 0 0 0 0 0 0 0 | 0 0 0 0 0 0 0 0 Initial state(0x8000) // - switch (isr_data & 0xFF) { + // x x x x x x x x | 0 0 0 0 0 0 0 0 midway(0-7 bits received) + // x x x x x x x x | *1 0 0 0 0 0 0 0 midway(8 bits received) + // b6 b5 b4 b3 b2 b1 b0 1 | 0 *1 0 0 0 0 0 0 XT_IBM-midway ^1 + // b7 b6 b5 b4 b3 b2 b1 b0 | 0 *1 0 0 0 0 0 0 AT-midway ^1 + // b7 b6 b5 b4 b3 b2 b1 b0 | 1 *1 0 0 0 0 0 0 XT_Clone-done ^3 + // b6 b5 b4 b3 b2 b1 b0 1 | 1 *1 0 0 0 0 0 0 XT_IBM-error ^3 + // pr b7 b6 b5 b4 b3 b2 b1 | 0 0 *1 0 0 0 0 0 AT-midway[b0=0] + // b7 b6 b5 b4 b3 b2 b1 b0 | 1 0 *1 0 0 0 0 0 XT_IBM-done ^2 + // pr b7 b6 b5 b4 b3 b2 b1 | 1 0 *1 0 0 0 0 0 AT-midway[b0=1] ^2 + // b7 b6 b5 b4 b3 b2 b1 b0 | 1 1 *1 0 0 0 0 0 XT_IBM-error-done + // x x x x x x x x | x 1 1 0 0 0 0 0 illegal + // st pr b7 b6 b5 b4 b3 b2 | b1 b0 0 *1 0 0 0 0 AT-done + // x x x x x x x x | x x 1 *1 0 0 0 0 illegal + // all other states than above illegal + // + // ^1: AT and XT_IBM takes same state. + // ^2: AT and XT_IBM takes same state in case that AT b0 is 1, + // we have to check AT stop bit to discriminate between the two protocol. + switch (isr_state & 0xFF) { case 0b00000000: case 0b10000000: - case 0b01000000: + case 0b01000000: // ^1 case 0b00100000: // midway - return; + goto NEXT; + break; + case 0b11000000: // ^3 + { + uint8_t us = 100; + // wait for rising and falling edge of b7 of XT_IBM + while (!(IBMPC_CLOCK_PIN&(1<>8; + ibmpc_protocol = IBMPC_PROTOCOL_XT_CLONE; + goto DONE; + } + } break; - case 0b11000000: - // XT Clone-done - recv_data = recv_data<<8; - recv_data |= (isr_data>>8) & 0xFF; + case 0b11100000: + // XT_IBM-error-done + ibmpc_isr_debug = isr_state; + isr_state = isr_state>>8; + ibmpc_protocol = IBMPC_PROTOCOL_XT_ERROR; goto DONE; break; - case 0b10100000: + case 0b10100000: // ^2 { uint8_t us = 100; - // wait for rising and falling edge of AT stop bit + // wait for rising and falling edge of AT stop bit to discriminate between XT and AT while (!(IBMPC_CLOCK_PIN&(1<>8) & 0xFF; + // no stop bit: XT_IBM-done + ibmpc_isr_debug = isr_state; + isr_state = isr_state>>8; + ibmpc_protocol = IBMPC_PROTOCOL_XT_IBM; goto DONE; } } @@ -276,31 +359,61 @@ PINB|=0x01; case 0b01010000: case 0b11010000: // AT-done - recv_data = recv_data<<8; - recv_data |= (isr_data>>6) & 0xFF; + // TODO: parity check? + ibmpc_isr_debug = isr_state; + // stop bit check + if (isr_state & 0x8000) { + ibmpc_protocol = IBMPC_PROTOCOL_AT; + } else { + // Zenith Z-150 AT(beige/white lable) asserts stop bit as low + // https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#zenith-z-150-beige + ibmpc_protocol = IBMPC_PROTOCOL_AT_Z150; + } + isr_state = isr_state>>6; goto DONE; break; case 0b01100000: - case 0b11100000: case 0b00110000: case 0b10110000: case 0b01110000: case 0b11110000: default: // xxxx_oooo(any 1 in low nibble) - recv_data = isr_data; + // Illegal + ibmpc_isr_debug = isr_state; + ibmpc_error = IBMPC_ERR_ILLEGAL; + goto ERROR; break; } + +ERROR: + // error: eeFF + recv_data = (ibmpc_error<<8) | 0x00FF; + goto CLEAR; DONE: - // TODO: check protocol change to support keyboard howswap - // not correct if there is clock edge within short time like 100us after receving data - // TODO: process error code: 0x00(AT), 0xFF(XT) in particular - isr_data = 0x8000; // clear to next data + if ((isr_state & 0x00FF) == 0x00FF) { + // receive error code 0xFF + ibmpc_error = IBMPC_ERR_FF; + goto ERROR; + } + if (HI8(recv_data) != 0xFF && LO8(recv_data) != 0xFF) { + // buffer full + ibmpc_error = IBMPC_ERR_FULL; + goto ERROR; + } + // store data + recv_data = recv_data<<8; + recv_data |= isr_state & 0xFF; +CLEAR: + // clear for next data + isr_state = 0x8000; +NEXT: return; } /* send LED state to keyboard */ void ibmpc_host_set_led(uint8_t led) { - ibmpc_host_send(0xED); - ibmpc_host_send(led); + if (0xFA == ibmpc_host_send(0xED)) { + ibmpc_host_send(led); + } }