CH Tech EM405D - Manual (Page 27)

21
Example 4: Read 32 words starting at address 0x0 followed by 32 words starting at address 0x80
starting address = 0x0
block size = 32
number of blocks = 2
address increment = 128
4.3.4.1
Block Write command
The Block Write command writes a block of data to an M-module. A maximum of 1024 bytes
can be written in a single command. The number of bytes written in any given command is
equal to:
number of bytes = number of blocks * block size * word size
The block write command consists of nine command bytes and any number (up to 1024) of data
bytes. The return value is a single status byte indicating the success of the command.
Command Syntax:
0x40 md as ws ad ai nh nl bs d1 d0 …
Return:
SC
where
md = module (0 = invalid, 1 = M-module A, 2 = M-module B)
as = address space (0 = I/O, 1 = future use)
ws = word size (2 = 16-bit word, other values for future use)
ad = starting address (0 to FF)
ai = address increment (number to increment address by after each write)
nh = number of blocks to read (upper 4 bits)
nl = number of blocks to read (lower 8 bits)
bs = block size in words (i.e., number of words per block)
d1 = data (MSB)
d0 = data (LSB)
… = the number of data bytes = ws 
bs

nb
SC = Status Code
Example (values shown hex):
To write the data values 0x1234, 0x5678, 0x9ABC to M-module A starting at I/O Register 4, send the
following command:
Command: cd md as ws ad ai nh nl bs dh1 dl1 dh2 dl2 dh3 dl3
Send: 40 01 00 02 04 02 00 03 01 12 34 56 78 9A BC
Receive: 00 (if successful)