+/*
+ * (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
/**
*
* Pin assignments
*
- * | Z180-Sig | AVR-Port | Dir | Special Function |
- * +------------+---------------+-------+-----------------------+
- * | A0 | PA 0 | O | |
- * | A1 | PA 1 | O | |
- * | A2 | PA 2 | O | |
- * | A3 | PA 3 | O | |
- * | A4 | PA 4 | O | |
- * | A5 | PA 5 | O | |
- * | A6 | PA 6 | O | |
- * | A7 | PA 7 | O | |
- * | A8 | PC 0 | O | |
- * | A9 | PC 1 | O | |
- * | A10 | PC 2 | O | |
- * | A11 | PC 3 | O | |
- * | A12 | PC 4 | O | |
- * | A13 | PC 5 | O | |
- * | A14 | PC 6 | O | |
- * | A15 | PC 7 | O | |
- * | A16 | PE 2 | O | |
- * | A17 | PE 3 | O | |
- * | A18 | PE 4 | O | |
- * | D0 | PF 0 | I/O | |
- * | D1 | PF 1 | I/O | |
- * | D2 | PF 2 | I/O | |
- * | D3 | PF 3 | I/O | |
- * | D4 | PF 4 | I/O | |
- * | D5 | PF 5 | I/O | |
- * | D6 | PF 6 | I/O | |
- * | D7 | PF 7 | I/O | |
- * | RD | PD 3 | O | |
- * | WR | PD 2 | O | |
- * | MREQ | PD 4 | O | |
- * | RST | PD 5 | O | |
- * | BUSREQ | PD 7 | O | |
- * | BUSACK | PD 6 | I | |
- * | IOCS1 | PE 5 | I | |
- * |* HALT | P | | |
- * |* NMI | P | | |
- * | | P | | |
- * | | P | | af1 USART1_TX |
- * | | P | | af1 USART1_RX |
- * | | P |JTDI | remap SPI1_NSS' |
- * | | P |JTDO | remap SPI1_SCK' |
- * | | P |JTRST | remap SPI1_MISO' |
- * | | P | | remap SPI1_MOSI' |
- * | | P | | af1 OSC32 |
- * | | P | | af1 OSC32 |
-
+ * | Z180-Sig | AVR-Port | Dir |
+ * +------------+---------------+-------+
+ * | A0 | PA 0 | O |
+ * | A1 | PA 1 | O |
+ * | A2 | PA 2 | O |
+ * | A3 | PA 3 | O |
+ * | A4 | PA 4 | O |
+ * | A5 | PA 5 | O |
+ * | A6 | PA 6 | O |
+ * | A7 | PA 7 | O |
+ * | A8 | PC 0 | O |
+ * | A9 | PC 1 | O |
+ * | A10 | PC 2 | O |
+ * | A11 | PC 3 | O |
+ * | A12 | PC 4 | O |
+ * | A13 | PC 5 | O |
+ * | A14 | PC 6 | O |
+ * | A15 | PC 7 | O |
+ * | A16 | PE 2 | O |
+ * | A17 | PE 3 | O |
+ * | A18 | PE 4 | O |
+ * | D0 | PF 0 | I/O |
+ * | D1 | PF 1 | I/O |
+ * | D2 | PF 2 | I/O |
+ * | D3 | PF 3 | I/O |
+ * | D4 | PF 4 | I/O |
+ * | D5 | PF 5 | I/O |
+ * | D6 | PF 6 | I/O |
+ * | D7 | PF 7 | I/O |
+ * | RD | PD 3 | O |
+ * | WR | PD 2 | O |
+ * | MREQ | PD 4 | O |
+ * | RST | PD 5 | O |
+ * | BUSREQ | PD 7 | O |
+ * | BUSACK | PD 6 | I |
+ * |
+ * | Optional
+ * +------------------------------------+
+ * | STEP | PG 0 | O |
+ * | RUN | PG 1 | O |
+ * | WAIT | PG 2 | I |
*/
-#include "common.h"
+
+#include "z80-if.h"
#include <util/atomic.h>
#include "debug.h"
-#include "z80-if.h"
-
+#include "config.h"
+#include "env.h"
//#define P_ZCLK PORTB
#define PIN_BUSACK PIND
#define BUSACK 6
#define DDR_BUSACK DDRD
-//#define P_HALT PORTA
-//#define HALT 12
-#define P_IOCS1 PORTE
-#define IOCS1 5
-#define DDR_IOCS1 DDRE
-//#define P_NMI PORTB
-//#define NMI 7
#define P_RST PORTD
+#define PIN_RST PIND
#define DDR_RST DDRD
#define RST 5
#define Z80_O_BUSREQ SBIT(P_BUSREQ, 7)
//#define Z80_O_NMI SBIT(P_NMI, )
#define Z80_O_RST SBIT(P_RST, 5)
+#define Z80_I_RST SBIT(PIN_RST, 5)
#define Z80_I_BUSACK SBIT(PIN_BUSACK, 6)
//#define Z80_I_HALT SBIT(P_HALT, )
+/* Optional */
+#define P_RUN PORTG
+#define RUN 1
+#define DDR_RUN DDRG
+#define P_STEP PORTG
+#define STEP 0
+#define DDR_STEP DDRG
+#define P_WAIT PORTG
+#define WAIT 2
+#define DDR_WAIT DDRG
+/* All three signals are on the same Port (PortG) */
+#define PORT_SS PORTG
+#define DDR_SS DDRG
+#define PIN_SS PING
+#define Z80_O_RUN SBIT(PORT_SS, RUN)
+#define Z80_O_STEP SBIT(PORT_SS, STEP)
+#define Z80_I_WAIT SBIT(PORT_SS, WAIT)
+
+
+#define BUS_TO 20
+
#define MASK(n) ((1<<(n))-1)
#define SMASK(w,s) (MASK(w) << (s))
-typedef union {
- uint32_t l;
- uint16_t w[2];
- uint8_t b[4];
-} addr_t;
+static zstate_t zstate;
+static volatile uint8_t timer; /* used for bus timeout */
+static bool reset_polarity;
+/*---------------------------------------------------------*/
+/* 10Hz timer interrupt generated by OC4A */
+/*---------------------------------------------------------*/
-static zstate_t zstate;
+ISR(TIMER5_COMPA_vect)
+{
+
+ uint8_t i = timer;
+
+ if (i)
+ timer = i - 1;
+}
/*--------------------------------------------------------------------------*/
-static void z80_addrbus_set_tristate(void)
+static void z80_addrbus_set_in(void)
{
/* /MREQ, /RD, /WR: Input, no pullup */
DDR_MREQ &= ~(_BV(MREQ) | _BV(RD) | _BV(WR));
DDR_ADL = 0;
P_ADH = 0;
DDR_ADH = 0;
- PIN_ADB = P_ADB & ~(MASK(ADB_WIDTH) << ADB_SHIFT);
+ PIN_ADB = P_ADB & (MASK(ADB_WIDTH) << ADB_SHIFT);
DDR_ADB = DDR_ADB & ~(MASK(ADB_WIDTH) << ADB_SHIFT);
}
-static void z80_addrbus_set_active(void)
+static void z80_addrbus_set_out(void)
{
/* /MREQ, /RD, /WR: Output and high */
Z80_O_MREQ = 1;
DDR_DB = 0xff;
}
+static void z80_reset_active(void)
+{
+ if (reset_polarity)
+ Z80_O_RST = 1;
+ else
+ Z80_O_RST = 0;
+}
+
+static void z80_reset_inactive(void)
+{
+ if (reset_polarity)
+ Z80_O_RST = 0;
+ else
+ Z80_O_RST = 1;
+}
static void z80_reset_pulse(void)
{
- Z80_O_RST = 0;
+ z80_reset_active();
_delay_us(10);
- Z80_O_RST = 1;
+ z80_reset_inactive();
}
void z80_setup_bus(void)
{
- /* /ZRESET: Output and low */
- Z80_O_RST = 0;
- DDR_RST |= _BV(RST);
+ ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
- /* /BUSREQ: Output and high */
- Z80_O_BUSREQ = 1;
- DDR_BUSREQ |= _BV(BUSREQ);
+ /* /ZRESET: Input, no pullup */
+ DDR_RST &= ~_BV(RST);
+ Z80_O_RST = 0;
- /* /BUSACK: Input, no pullup */
- DDR_BUSACK &= ~_BV(BUSACK);
- P_BUSACK &= ~_BV(BUSACK);
+ /* /BUSREQ: Output and high */
+ Z80_O_BUSREQ = 1;
+ DDR_BUSREQ |= _BV(BUSREQ);
- /* /IOCS1: Input, no pullup */
- DDR_IOCS1 &= ~_BV(IOCS1);
- P_IOCS1 &= ~_BV(IOCS1);
+ /* /BUSACK: Input, no pullup */
+ DDR_BUSACK &= ~_BV(BUSACK);
+ P_BUSACK &= ~_BV(BUSACK);
- z80_addrbus_set_tristate();
- z80_dbus_set_in();
+ z80_addrbus_set_in();
+ z80_dbus_set_in();
+
+ if (getenv_yesno(PSTR(ENV_SINGLESTEP))) {
+ /* /RUN & /STEP: output, /WAIT: input */
+
+ PORT_SS = (PORT_SS & ~_BV(RUN)) | _BV(STEP);
+ DDR_SS = (DDR_SS & ~_BV(WAIT)) | _BV(RUN) | _BV(STEP);
+ }
+
+ reset_polarity = Z80_I_RST;
+ z80_reset_active();
+ DDR_RST |= _BV(RST);
+
+ zstate = RESET;
+ }
+
+ /* Timer 5 */
+ PRR1 &= ~_BV(PRTIM5);
+ OCR5A = F_CPU / 1024 / 10 - 1; /* Timer: 10Hz interval (OC4A) */
+ TCCR5B = (0b01<<WGM52)|(0b101<<CS40); /* CTC Mode, Prescaler 1024 */
+ TIMSK5 = _BV(OCIE5A); /* Enable oca interrupt */
- zstate = RESET;
}
static void z80_busreq_hpulse(void)
{
z80_dbus_set_in();
- z80_addrbus_set_tristate();
+ z80_addrbus_set_in();
+#if 0
ATOMIC_BLOCK(ATOMIC_FORCEON) {
Z80_O_BUSREQ = 1;
Z80_O_BUSREQ = 1; /* 2 AVR clock cycles */
Z80_O_BUSREQ = 0; /* 2 AVR clock cycles */
}
+#endif
+
+#if 1
+ ATOMIC_BLOCK(ATOMIC_FORCEON) {
+ Z80_O_BUSREQ = 1;
+
+ do {
+ if (Z80_I_BUSACK == 1) {
+ Z80_O_BUSREQ = 0;
+ break;
+ }
+ } while (1);
+ }
+#endif
if (zstate & ZST_ACQUIRED) {
- while(Z80_I_BUSACK == 1)
+ timer = BUS_TO;
+ while (Z80_I_BUSACK == 1 && timer)
;
- z80_addrbus_set_active();
+ if (Z80_I_BUSACK == 0)
+ z80_addrbus_set_out();
}
}
/*
- + | | | | |
+ + | | | | |
+ State | RESET | RESET_AQRD | RUNNING | RUNNING_AQRD |
- + | | | | |
- + | 0 | 1 | 2 | 3 |
-Event + | | | | |
+ + | | | | |
+ + | 0 | 1 | 2 | 3 |
+Event + | | | | |
----------------+---------------+---------------+---------------+---------------+
- | | | | |
-Reset | 0 | 0 | 0 | 0 |
- | | | | |
- | | | | |
-Request | 1 | | 3 | |
- | | | | |
- | | | | |
-Release | | 0 | | 2 |
- | | | | |
- | | | | |
-Run | 2 | 3 | | |
- | | | | |
- | | | | |
-Restart | | | 2 | 3 |
- | | | | |
- | | | | |
-M_Cycle | | | | 3 |
- | | | | |
- | | | | |
+ | | | | |
+Reset | 0 | 0 | 0 | 0 |
+ | | | | |
+ | | | | |
+Request | 1 | | 3 | |
+ | | | | |
+ | | | | |
+Release | | 0 | | 2 |
+ | | | | |
+ | | | | |
+Run | 2 | 3 | | |
+ | | | | |
+ | | | | |
+Restart | | | 2 | 3 |
+ | | | | |
+ | | | | |
+M_Cycle | | | | 3 |
+ | | | | |
+ | | | | |
*/
zstate_t z80_bus_cmd(bus_cmd_t cmd)
case Reset:
z80_dbus_set_in();
- z80_addrbus_set_tristate();
- Z80_O_RST = 0;
+ z80_addrbus_set_in();
+ z80_reset_active();
Z80_O_BUSREQ = 1;
zstate = RESET;
break;
switch (zstate) {
case RESET:
Z80_O_BUSREQ = 0;
- Z80_O_RST = 1;
- while(Z80_I_BUSACK == 1)
+ z80_reset_inactive();
+ timer = BUS_TO;
+ while (Z80_I_BUSACK == 1 && timer)
;
- z80_addrbus_set_active();
- zstate = RESET_AQRD;
+ if (Z80_I_BUSACK == 0) {
+ z80_addrbus_set_out();
+ zstate = RESET_AQRD;
+ } else {
+ z80_reset_active();
+ Z80_O_BUSREQ = 1;
+ }
break;
case RUNNING:
Z80_O_BUSREQ = 0;
- while(Z80_I_BUSACK == 1)
+ timer = BUS_TO;
+ while (Z80_I_BUSACK == 1 && timer)
;
- z80_addrbus_set_active();
- zstate = RUNNING_AQRD;
+ if (Z80_I_BUSACK == 0) {
+ z80_addrbus_set_out();
+ zstate = RUNNING_AQRD;
+ } else {
+ Z80_O_BUSREQ = 1;
+ }
break;
default:
switch (zstate) {
case RESET_AQRD:
z80_dbus_set_in();
- z80_addrbus_set_tristate();
- Z80_O_RST = 0;
+ z80_addrbus_set_in();
+ z80_reset_active();
Z80_O_BUSREQ = 1;
zstate = RESET;
break;
case RUNNING_AQRD:
z80_dbus_set_in();
- z80_addrbus_set_tristate();
+ z80_addrbus_set_in();
Z80_O_BUSREQ = 1;
zstate = RUNNING;
break;
case Run:
switch (zstate) {
case RESET:
- Z80_O_RST = 1;
+ z80_reset_inactive();
zstate = RUNNING;
break;
case RESET_AQRD:
z80_dbus_set_in();
- z80_addrbus_set_tristate();
+ z80_addrbus_set_in();
z80_reset_pulse();
- z80_addrbus_set_active();
+ z80_addrbus_set_out();
zstate = RUNNING_AQRD;
break;
default:
case M_Cycle:
switch (zstate) {
case RUNNING_AQRD:
- z80_busreq_hpulse();
+ z80_busreq_hpulse(); /* TODO: */
break;
default:
break;
//inline __attribute__ ((always_inline))
void z80_setaddress(uint32_t addr)
{
- addr_t x; x.l = addr;
-
- P_ADL = x.b[0];
- P_ADH = x.b[1];
- PIN_ADB = ((x.b[2] << ADB_SHIFT) ^ P_ADB) & MASK(ADB_WIDTH) << ADB_SHIFT ;
+ P_ADL = addr;
+ P_ADH = (addr & 0xff00) >> 8;
+ PIN_ADB = (((addr >> 16) << ADB_SHIFT) ^ P_ADB) & MASK(ADB_WIDTH) << ADB_SHIFT;
}
void z80_write(uint32_t addr, uint8_t data)
{
z80_dbus_set_out();
Z80_O_MREQ = 0;
+ P_DB = data;
while(length--) {
z80_setaddress(addr++);
+ Z80_O_WR = 0;
+ Z80_O_WR = 0;
+ Z80_O_WR = 1;
+ }
+ Z80_O_MREQ = 1;
+}
+
+void z80_write_block_P(const FLASH uint8_t *src, uint32_t dest, uint32_t length)
+{
+ uint8_t data;
+
+ z80_dbus_set_out();
+ Z80_O_MREQ = 0;
+ while(length--) {
+ z80_setaddress(dest++);
+ data = *src++;
P_DB = data;
P_DB = data;
Z80_O_WR = 0;
Z80_O_MREQ = 1;
}
-void z80_write_block(const __flash uint8_t *src, uint32_t dest, uint32_t length)
+void z80_write_block(const uint8_t *src, uint32_t dest, uint32_t length)
{
uint8_t data;
Z80_O_MREQ = 1;
}
+void z80_read_block (uint8_t *dest, uint32_t src, size_t length)
+{
+ uint8_t data;
+
+ Z80_O_MREQ = 0;
+ z80_dbus_set_in();
+ while(length--) {
+ z80_setaddress(src++);
+ Z80_O_RD = 0;
+ Z80_O_RD = 0;
+ Z80_O_RD = 0;
+ data = PIN_DB;
+ Z80_O_RD = 1;
+ *dest++ = data;
+ }
+ Z80_O_MREQ = 1;
+}
+
+
/*
0179' rx.bs_mask: ds 1 ; (buf_len - 1)
017A' rx.in_idx: ds 1 ;
{
fifo_dsc[f].base = addr;
- if (addr != 0) {
-
-DBG_P(2, "z80_memfifo_init: %i, %lx\n", f, addr);
+ if (addr != 0) {
z80_bus_cmd(Request);
fifo_dsc[f].mask = z80_read(addr + FIFO_BUFSIZE_MASK);
fifo_dsc[f].idx_in = z80_read(addr + FIFO_INDEX_IN);
fifo_dsc[f].idx_out = z80_read(addr + FIFO_INDEX_OUT);
z80_bus_cmd(Release);
+
+ if (fifo_dsc[f].idx_in != 0 || fifo_dsc[f].idx_out != 0) {
+ DBG_P(1, "## z80_memfifo_init: %i, %lx, in: %.2x, out: %.2x, mask: %.2x\n",
+ f, addr, fifo_dsc[f].idx_in, fifo_dsc[f].idx_out, fifo_dsc[f].mask);
+ }
}
}
int z80_memfifo_is_full(const fifo_t f)
{
- int rc = 1;
+ int rc = 0;
if (fifo_dsc[f].base != 0) {
z80_bus_cmd(Request);