Merge branch 'dev'

doc/README-pico.txt

@@ -27,4 +27,19 @@ on the breadbaord. The card drives can draw 100 mA, so better provide
 sufficient GND. Also please note the two blocking capacitors, these are
 to keep radio emissions low.
 
+picoboard4:
+I removed the monochrome LED and instead added a breakout board with a
+WS2811 RGB LED. With this we can show stati of the machine by using
+different colors, show access to the disk drives, or blink it from
+the emulated CPU's. These RGB LED's need 5V power, which is available
+at pin 40 comming from the USB connection. The data in pin is connected
+to GPIO 14 and the 3.3V logic level from the GPIO is fine to program the
+LED, a logic level shifter is not needed.
+
+pico-rtc-*
+I added a battery backed RTC, so that date and time stays current, without
+the need to set it all the time. For my breadboard research system I used
+the stackable module from Waveshare:
+https://www.waveshare.com/wiki/Pico-RTC-DS3231
+
 How to build the application for this board is explained in picosim/README.

picosim/CMakeLists.txt

@@ -48,6 +48,9 @@ add_executable(${PROJECT_NAME}
 	${Z80PACK}/z80core/simz80.c
 )
 
+# generate the header file into the source tree
+pico_generate_pio_header(${PROJECT_NAME} ${CMAKE_CURRENT_LIST_DIR}/WS2812.pio)
+
 target_include_directories(${PROJECT_NAME} PUBLIC
 	${CMAKE_SOURCE_DIR}
 	${Z80PACK}/iodevices
@@ -56,6 +59,7 @@ target_include_directories(${PROJECT_NAME} PUBLIC
 
 add_subdirectory(no-OS-FatFS-SD-SDIO-SPI-RPi-Pico/src FatFs)
 add_subdirectory(stdio_msc_usb)
+add_subdirectory(ds3231)
 
 target_compile_definitions(${PROJECT_NAME} PRIVATE
 	PICO_STACK_SIZE=4096
@@ -78,13 +82,17 @@ target_compile_options(${PROJECT_NAME} PUBLIC -Wno-unused-parameter)
 
 # for Pico
 target_link_libraries(${PROJECT_NAME}
+	hardware_i2c
+	pico-ds3231
 	pico_stdlib
 	stdio_msc_usb
 	tinyusb_device
 	no-OS-FatFS-SD-SDIO-SPI-RPi-Pico
 )
 # for Pico W
 #target_link_libraries(${PROJECT_NAME}
+#	hardware_i2c
+#	pico-ds3231
 #	pico_stdlib
 #	pico_cyw43_arch_none
 #	stdio_msc_usb

picosim/WS2812.pio

@@ -0,0 +1,85 @@
+;
+; Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+;
+; SPDX-License-Identifier: BSD-3-Clause
+;
+
+.program ws2812
+.side_set 1
+
+.define public T1 2
+.define public T2 5
+.define public T3 3
+
+.lang_opt python sideset_init = pico.PIO.OUT_HIGH
+.lang_opt python out_init     = pico.PIO.OUT_HIGH
+.lang_opt python out_shiftdir = 1
+
+.wrap_target
+bitloop:
+    out x, 1       side 0 [T3 - 1] ; Side-set still takes place when instruction stalls
+    jmp !x do_zero side 1 [T1 - 1] ; Branch on the bit we shifted out. Positive pulse
+do_one:
+    jmp  bitloop   side 1 [T2 - 1] ; Continue driving high, for a long pulse
+do_zero:
+    nop            side 0 [T2 - 1] ; Or drive low, for a short pulse
+.wrap
+
+% c-sdk {
+#include "hardware/clocks.h"
+
+static inline void ws2812_program_init(PIO pio, uint sm, uint offset, uint pin, float freq, bool rgbw) {
+
+    pio_gpio_init(pio, pin);
+    pio_sm_set_consecutive_pindirs(pio, sm, pin, 1, true);
+
+    pio_sm_config c = ws2812_program_get_default_config(offset);
+    sm_config_set_sideset_pins(&c, pin);
+    sm_config_set_out_shift(&c, false, true, rgbw ? 32 : 24);
+    sm_config_set_fifo_join(&c, PIO_FIFO_JOIN_TX);
+
+    int cycles_per_bit = ws2812_T1 + ws2812_T2 + ws2812_T3;
+    float div = clock_get_hz(clk_sys) / (freq * cycles_per_bit);
+    sm_config_set_clkdiv(&c, div);
+
+    pio_sm_init(pio, sm, offset, &c);
+    pio_sm_set_enabled(pio, sm, true);
+}
+%}
+
+.program ws2812_parallel
+
+.define public T1 2
+.define public T2 5
+.define public T3 3
+
+.wrap_target
+    out x, 32
+    mov pins, !null [T1-1]
+    mov pins, x     [T2-1]
+    mov pins, null  [T3-2]
+.wrap
+
+% c-sdk {
+#include "hardware/clocks.h"
+
+static inline void ws2812_parallel_program_init(PIO pio, uint sm, uint offset, uint pin_base, uint pin_count, float freq) {
+    for(uint i=pin_base; i<pin_base+pin_count; i++) {
+        pio_gpio_init(pio, i);
+    }
+    pio_sm_set_consecutive_pindirs(pio, sm, pin_base, pin_count, true);
+
+    pio_sm_config c = ws2812_parallel_program_get_default_config(offset);
+    sm_config_set_out_shift(&c, true, true, 32);
+    sm_config_set_out_pins(&c, pin_base, pin_count);
+    sm_config_set_set_pins(&c, pin_base, pin_count);
+    sm_config_set_fifo_join(&c, PIO_FIFO_JOIN_TX);
+
+    int cycles_per_bit = ws2812_parallel_T1 + ws2812_parallel_T2 + ws2812_parallel_T3;
+    float div = clock_get_hz(clk_sys) / (freq * cycles_per_bit);
+    sm_config_set_clkdiv(&c, div);
+
+    pio_sm_init(pio, sm, offset, &c);
+    pio_sm_set_enabled(pio, sm, true);
+}
+%}

picosim/disks.c

@@ -29,6 +29,7 @@
 
 #include "sd-fdc.h"
 #include "disks.h"
+#include "rgbled.h"
 
 FIL sd_file;	/* at any time we have only one file open */
 FRESULT sd_res;	/* result code from FatFS */
@@ -268,22 +269,28 @@ BYTE read_sec(int drive, int track, int sector, WORD addr)
 	if ((stat = prep_io(drive, track, sector, addr)) != FDC_STAT_OK)
 		return stat;
 
+	put_pixel(0x440000); /* LED green */
+
 	/* read sector into memory */
 	sd_res = f_read(&sd_file, &dsk_buf[0], SEC_SZ, &br);
 	if (sd_res == FR_OK) {
 		if (br < SEC_SZ) {	/* UH OH */
 			f_close(&sd_file);
-			return FDC_STAT_READ;
+			stat = FDC_STAT_READ;
 		} else {
 			f_close(&sd_file);
 			for (i = 0; i < SEC_SZ; i++)
 				dma_write(addr + i, dsk_buf[i]);
-			return FDC_STAT_OK;
+			stat = FDC_STAT_OK;
 		}
 	} else {
 		f_close(&sd_file);
-		return FDC_STAT_READ;
+		stat = FDC_STAT_READ;
 	}
+
+	sleep_us(300);
+	put_pixel(0x000000); /* LED off */
+	return stat;
 }
 
 /*
@@ -299,22 +306,28 @@ BYTE write_sec(int drive, int track, int sector, WORD addr)
 	if ((stat = prep_io(drive, track, sector, addr)) != FDC_STAT_OK)
 		return stat;
 
+	put_pixel(0x004400); /* LED red */
+
 	/* write sector to disk image */
 	for (i = 0; i < SEC_SZ; i++)
 		dsk_buf[i] = dma_read(addr + i);
 	sd_res = f_write(&sd_file, &dsk_buf[0], SEC_SZ, &br);
 	if (sd_res == FR_OK) {
 		if (br < SEC_SZ) {	/* UH OH */
 			f_close(&sd_file);
-			return FDC_STAT_WRITE;
+			stat = FDC_STAT_WRITE;
 		} else {
 			f_close(&sd_file);
-			return FDC_STAT_OK;
+			stat = FDC_STAT_OK;
 		}
 	} else {
 		f_close(&sd_file);
-		return FDC_STAT_WRITE;
+		stat = FDC_STAT_WRITE;
 	}
+
+	sleep_us(300);
+	put_pixel(0x000000); /* LED off */
+	return stat;
 }
 
 /*

picosim/ds3231/CMakeLists.txt

@@ -0,0 +1,17 @@
+add_library(pico-ds3231 INTERFACE)
+
+target_include_directories(pico-ds3231
+  INTERFACE
+  ${CMAKE_CURRENT_LIST_DIR}
+)
+
+target_link_libraries(pico-ds3231
+  INTERFACE
+  hardware_i2c
+)
+
+target_sources(pico-ds3231
+  INTERFACE
+  ${CMAKE_CURRENT_LIST_DIR}/ds3231.c
+  ${CMAKE_CURRENT_LIST_DIR}/ds3231.h
+)