From d9a56801f7124e5b499efd82a4582808bfd81ce2 Mon Sep 17 00:00:00 2001
From: folkert van heusden <mail@vanheusden.com>
Date: Thu, 17 Mar 2022 21:22:26 +0100
Subject: [PATCH] misc esp32 tweaks

---
 bus.cpp    | 18 +++++++++---------
 cpu.cpp    | 16 +++++-----------
 memory.cpp |  8 ++++++++
 rk05.cpp   |  2 ++
 4 files changed, 24 insertions(+), 20 deletions(-)

diff --git a/bus.cpp b/bus.cpp
index a0d21e2..a38aa08 100644
--- a/bus.cpp
+++ b/bus.cpp
@@ -13,19 +13,19 @@
 #include "tm-11.h"
 #include "tty.h"
 
-bus::bus() : c(nullptr), tm11(nullptr), rk05_(nullptr), rx02_(nullptr), tty_(nullptr)
-{
 #if defined(ESP32)
-	// ESP32 goes in a crash-loop when allocating 128kB
-	// see also https://github.com/espressif/esp-idf/issues/1934
-	int n = 12;
+// ESP32 goes in a crash-loop when allocating 128kB
+// see also https://github.com/espressif/esp-idf/issues/1934
+constexpr int n_pages = 12;
 #else
-	int n = 16;
+constexpr int n_pages = 16;
 #endif
 
-	m = new memory(n * 8192);
+bus::bus() : c(nullptr), tm11(nullptr), rk05_(nullptr), rx02_(nullptr), tty_(nullptr)
+{
+	m = new memory(n_pages * 8192);
 
-	for(int i=0; i<n; i++) {
+	for(int i=0; i<n_pages; i++) {
 		pages[i].par = (i & 7) * 8192 / 64;
 		pages[i].pdr = (3 << 1) | (0 << 4) | (0 << 6) | ((8192 / (32 * 2)) << 8);
 	}
@@ -241,7 +241,7 @@ uint16_t bus::read(const uint16_t a, const bool word_mode, const bool use_prev)
 		D(fprintf(stderr, "UNHANDLED read %o(%c)\n", a, word_mode ? 'B' : ' ');)
 
 		if (a == 0177760)
-			return 0167777;  // TODO; get this from memory.cpp min(memsize, 64kB - 4kB)
+			return std::min(n_pages * 8192, 65536) - 4096;
 
 //		c -> busError();
 
diff --git a/cpu.cpp b/cpu.cpp
index d7d1fa0..f097165 100644
--- a/cpu.cpp
+++ b/cpu.cpp
@@ -1517,14 +1517,6 @@ bool cpu::step()
 	if (getPC() & 1)
 		busError();
 
-	if (getPC() == 06746)
-	{
-		FILE *fh = fopen("debug.dat", "wb");
-		for(int i=0; i<256; i++)
-			fputc(b -> readByte(getPC() + i), fh);
-		fclose(fh);
-	}
-
 	disassemble();
 
 	b -> setMMR2(getPC());
@@ -1547,9 +1539,11 @@ bool cpu::step()
 
 	{
 		FILE *fh = fopen("fail.dat", "wb");
-		for(int i=0; i<256; i++)
-			fputc(b -> readByte(getPC() - 2 + i), fh);
-		fclose(fh);
+		if (fh) {
+			for(int i=0; i<256; i++)
+				fputc(b -> readByte(getPC() - 2 + i), fh);
+			fclose(fh);
+		}
 	}
 	busError();
 	exit(1);
diff --git a/memory.cpp b/memory.cpp
index de5460a..bc1b9b8 100644
--- a/memory.cpp
+++ b/memory.cpp
@@ -1,11 +1,19 @@
 // (C) 2018 by Folkert van Heusden
 // Released under Apache License v2.0
+#if defined(ESP32)
+#include <Arduino.h>
+#endif
 #include <string.h>
 
 #include "memory.h"
 
 memory::memory(const uint32_t size) : size(size)
 {
+#if defined(ESP32)
+	Serial.print(F("Memory size (in bytes, decimal): "));
+	Serial.println(size);
+#endif
+
 	m = new uint8_t[size]();
 }
 
diff --git a/rk05.cpp b/rk05.cpp
index 63c2a59..248c1b0 100644
--- a/rk05.cpp
+++ b/rk05.cpp
@@ -199,6 +199,8 @@ void rk05::writeWord(const uint16_t addr, uint16_t v)
 				while(temp > 0) {
 					uint32_t cur = std::min(uint32_t(sizeof xfer_buffer), temp);
 
+					yield();
+
 #if defined(ESP32)
 					if (fh.read(xfer_buffer, cur) != size_t(cur))
 						D(fprintf(stderr, "RK05 fread error: %s\n", strerror(errno));)