From 83c433c1421cefc538ab16605de412ead2c87f31 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Mon, 26 Dec 2016 12:48:49 -0500
Subject: [PATCH] Deviated from the data sheet, which seems likely to be
correct. Hence removed a whole load of the temporary logging.
---
Components/1770/1770.cpp | 33 ++++++++++++++++++++-------------
1 file changed, 20 insertions(+), 13 deletions(-)
diff --git a/Components/1770/1770.cpp b/Components/1770/1770.cpp
index a725a4770..e320d01f4 100644
--- a/Components/1770/1770.cpp
+++ b/Components/1770/1770.cpp
@@ -563,7 +563,6 @@ void WD1770::posit_event(Event new_event_type)
});
distance_into_section_ = 0;
is_reading_data_ = true;
- printf("\n");
goto type2_read_byte;
}
goto type2_read_data;
@@ -571,7 +570,7 @@ void WD1770::posit_event(Event new_event_type)
type2_read_byte:
WAIT_FOR_EVENT(Event::Token);
if(latest_token_.type != Token::Byte) goto type2_read_byte;
- data_ = latest_token_.byte_value; printf("%02x", data_);
+ data_ = latest_token_.byte_value;
update_status([] (Status &status) {
status.lost_data |= status.data_request;
status.data_request = true;
@@ -580,7 +579,6 @@ void WD1770::posit_event(Event new_event_type)
if(distance_into_section_ == 128 << header_[3])
{
distance_into_section_ = 0;
- printf("\n");
goto type2_check_crc;
}
goto type2_read_byte;
@@ -633,7 +631,7 @@ void WD1770::posit_event(Event new_event_type)
if(is_double_density_)
{
write_raw_short(Storage::Encodings::MFM::MFMAddressMark);
- write_byte((command_&0x01) ? Storage::Encodings::MFM::MFMDataAddressByte : Storage::Encodings::MFM::MFMDeletedDataAddressByte);
+ write_byte((command_&0x01) ? Storage::Encodings::MFM::MFMDeletedDataAddressByte : Storage::Encodings::MFM::MFMDataAddressByte);
}
else
{
@@ -642,20 +640,25 @@ void WD1770::posit_event(Event new_event_type)
WAIT_FOR_EVENT(Event::DataWritten);
distance_into_section_ = 0;
- printf("\n");
type2_write_loop:
- write_byte(data_); printf("%02x", data_);
- update_status([] (Status &status) {
- status.data_request = true;
- });
- WAIT_FOR_EVENT(Event::DataWritten);
+ /*
+ This deviates from the data sheet slightly since that would prima facie request one more byte
+ of data than is actually written — the last time around the loop it has transferred from the
+ data register to the data shift register, set data request, written the byte, checked that data
+ request has been satified, then finally considers whether all bytes are done. Based on both
+ natural expectations and the way that emulated machines responded, I believe that to be a
+ documentation error.
+ */
+ write_byte(data_);
distance_into_section_++;
- if(distance_into_section_ == 128 << header_[3])
+ if(distance_into_section_ < 128 << header_[3])
{
- printf("\n");
- goto type2_write_crc;
+ update_status([] (Status &status) {
+ status.data_request = true;
+ });
}
+ WAIT_FOR_EVENT(Event::DataWritten);
if(status_.data_request)
{
@@ -665,6 +668,10 @@ void WD1770::posit_event(Event new_event_type)
goto wait_for_command;
}
+ if(distance_into_section_ == 128 << header_[3])
+ {
+ goto type2_write_crc;
+ }
goto type2_write_loop;
type2_write_crc: