/// FUNCTION: - Add the number of rows requested to memory panel starting at <startAddress>
/// - Show 2 rows in memory panel previous to <startAddress> to see what instructions are before PC
/// - Don't show these previous 2 rows if <startAddress> is within 16 bytes from byte zero to avoid invalid
/// access in array.
/// RECEIVES CALLS FROM: -updatePanelsAndResetMenuItems()
/// -goButton_Click()
private void updateMemoryPanel(uint startAddress)
{
int rowToHighlight = 0; // hightlight first row to show starting address
this.memoryDataGridView.Rows.Clear();
uint wordSizeInBytes = 4; // 4 bytes = 1 word
uint oneMemRowInBytes = wordSizeInBytes * 4; // 4 words = 1 row
uint[] fourWordsFromMemory;
// set up to show previous 2 rows if <startAddress> is within 16 bytes from byte zero
if ((startAddress - (oneMemRowInBytes * 2)) >= 0)
{
startAddress = startAddress - (oneMemRowInBytes * 2); // show the first two rows previous to PC (program counter).
rowToHighlight = 2;
}
// Add the number of rows requested to memory panel.
// Add 2 rows in memory previous to PC
// TODO: catch excess of rows requested when the RAM doesn't have a lot of memory to display that fits in the all the requested rows
for (int i = 0; i < this.memoryPanelNoRowsToShow; i++)
{
fourWordsFromMemory = computer.getFourWordsFromMemory(startAddress);
// TODO: for now if out of range in memory address, print 0. Add a handler for out of bound memory address later.
// add one row in GridViewin order: address, hex1, hex2, hex3, h4, contents
//string currentHexAddress = "0x" + startAddress.ToString("X").PadLeft(8, '0');
this.memoryDataGridView.Rows.Add("0x" + startAddress.ToString("X").PadLeft(8, '0'),
fourWordsFromMemory[0].ToString("x").PadLeft(8, '0'),
fourWordsFromMemory[1].ToString("x").PadLeft(8, '0'),
fourWordsFromMemory[2].ToString("x").PadLeft(8, '0'),
fourWordsFromMemory[3].ToString("x").PadLeft(8, '0'));
//increment startAddress to get the next four words from registers
startAddress += oneMemRowInBytes;
}
// highlight feature for the start address row
if (memoryDataGridView.Rows.Count > 1)
{
memoryDataGridView.Rows[rowToHighlight].DefaultCellStyle.BackColor = Color.Blue;
}
}