new command: memsize. new function z80_memsize_detect().

4 files changed, 61 insertions, 33 deletions

diff --git a/avr/cmd_loadihex.c b/avr/cmd_loadihex.c
index d55a63a..a7c9238 100644
--- a/avr/cmd_loadihex.c
+++ b/avr/cmd_loadihex.c
@@ -12,34 +12,6 @@
 #include "debug.h"
 
 
-static uint32_t detect_ramsize(void)
-{
-	uint32_t addr;
-	uint8_t save_addr, save_0;
-	const uint8_t PATTERN_1	= 0x55;
-	const uint8_t PATTERN_2	= ~PATTERN_1;
-
-	if (!(z80_bus_cmd(Request) & ZST_ACQUIRED)) {
-		my_puts_P(PSTR("Bus timeout\n"));
-		return  0;
-	}
-
-	save_0 = z80_read(0);
-	z80_write(0, PATTERN_1);
-
-	for (addr=1; addr < CONFIG_SYS_RAMSIZE_MAX; addr <<= 1) {
-		save_addr = z80_read(addr);
-		z80_write(addr, PATTERN_2);
-		if (z80_read(0) != PATTERN_1 || z80_read(addr) != PATTERN_2)
-			break;
-		z80_write(addr, save_addr);
-	}
-	z80_write(0, save_0);
-	z80_bus_cmd(Release);
-
-	return addr;
-}
-
 typedef enum {
 	IHX_OK,
 	IHX_BROKEN,
@@ -149,15 +121,22 @@ command_ret_t do_loadihex(cmd_tbl_t *cmdtp UNUSED, uint_fast8_t flag UNUSED, int
 {
 	long offset = 0;
 	uint32_t base_address = 0;
-	uint32_t address_max = detect_ramsize();
 	uint32_t address_high = 0;
-	uint32_t address_low = address_max;
+	uint32_t address_max;
+	uint32_t address_low;
 	bool firstrec = true;
 	ihex_t rec;
 
 	if (argc > 1)
 		offset = strtol(argv[1], NULL, 16);
 
+	int32_t ram = z80_memsize_detect();
+	if (ram < 0)
+		cmd_error(CMD_RET_FAILURE, (ERRNUM) -ram, NULL);
+
+	address_max = ram;
+	address_low = address_max;
+
 	my_puts_P(PSTR("Waiting for Intel Hex Records...\n"));
 
 	while (ihex_get_record(&rec) > 0 &&
diff --git a/avr/cmd_mem.c b/avr/cmd_mem.c
index 7a8781c..d641410 100644
--- a/avr/cmd_mem.c
+++ b/avr/cmd_mem.c
@@ -13,11 +13,9 @@
  * Copied from FADS ROM, Dan Malek (dmalek@jlc.net)
  */
 
-#include "common.h"
-#include <ctype.h>
+#include "cmd_mem.h"
 #include <avr/interrupt.h>
 
-#include "command.h"
 #include "cli_readline.h"
 #include "print-utils.h"
 #include "con-utils.h"
@@ -55,6 +53,19 @@ static ERRNUM z180_read_buf(uint8_t *buf, uint32_t addr, uint8_t count)
 
 /*--------------------------------------------------------------------------*/
 
+command_ret_t do_mem_size(cmd_tbl_t *cmdtp UNUSED, uint_fast8_t flag UNUSED, int argc UNUSED, char * const argv[] UNUSED)
+{
+	int32_t ramsize = z80_memsize_detect();
+
+	if (ramsize < 0)
+		cmd_error(CMD_RET_FAILURE, (ERRNUM) -ramsize, PSTR("Couldn't access RAM"));
+
+	printf_P(PSTR("Detected RAM: Start %.5lx, End: %.5lx, Size: %.5lx (%ld dec)\n"),
+		0l, ramsize ? ramsize-1 : 0l, ramsize, ramsize);
+
+	return CMD_RET_SUCCESS;
+}
+
 /* Memory Display
  *
  * Syntax:
diff --git a/avr/command_tbl.c b/avr/command_tbl.c
index 232d718..5d185ba 100644
--- a/avr/command_tbl.c
+++ b/avr/command_tbl.c
@@ -75,6 +75,11 @@ CMD_TBL_ITEM(
 ),
 #endif
 CMD_TBL_ITEM(
+	msize,	1,	1,	do_mem_size,
+	"Detect memory size",
+	""
+),
+CMD_TBL_ITEM(
 	mstep,	2,	1,	do_busreq_pulse,
 	"execute one M cycle",
 	"[count]\n"
diff --git a/avr/z80-if.c b/avr/z80-if.c
index 6183849..6d83172 100644
--- a/avr/z80-if.c
+++ b/avr/z80-if.c
@@ -463,6 +463,39 @@ void z80_setaddress(uint32_t addr)
 	PIN_ADB = (((addr >> 16) << ADB_SHIFT) ^ P_ADB) & MASK(ADB_WIDTH) << ADB_SHIFT;
 }
 
+int32_t z80_memsize_detect(void)
+{
+	const uint8_t PATTERN_1	= 0x55;
+	const uint8_t PATTERN_2	= ~PATTERN_1;
+	uint32_t addr;
+
+	if (!(z80_bus_cmd(Request) & ZST_ACQUIRED))
+		return  -EBUSTO;
+
+	uint8_t ram_0 = z80_read(0);
+	uint8_t ram_1 = z80_read(1);
+
+	z80_write(0, ram_0 ^ 0xff);
+	z80_write(1, ram_1);
+	if ((z80_read(0) ^ ram_0) != 0xff) {
+		addr = 0;
+	} else {
+		z80_write(0, PATTERN_1);
+		for (addr=1; addr < CONFIG_SYS_RAMSIZE_MAX; addr <<= 1) {
+			uint8_t ram_i = z80_read(addr);
+			z80_write(addr, PATTERN_2);
+			if (z80_read(0) != PATTERN_1 || z80_read(addr) != PATTERN_2)
+				break;
+			z80_write(addr, ram_i);
+		}
+	}
+
+	z80_write(0, ram_0);
+	z80_bus_cmd(Release);
+
+	return addr;
+}
+
 void z80_write(uint32_t addr, uint8_t data)
 {
 	z80_setaddress(addr);