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/** @remote_bitbangpage OpenOCD Developer's Guide
The remote_bitbang JTAG driver is used to drive JTAG from a remote process. The
remote_bitbang driver communicates via TCP or UNIX sockets with some remote
process using an ASCII encoding of the bitbang interface. The remote process
presumably then drives the JTAG however it pleases. The remote process should
act as a server, listening for connections from the openocd remote_bitbang
driver.
The remote bitbang driver is useful for debugging software running on
processors which are being simulated.
The bitbang interface consists of the following functions.
blink on
Blink a light somewhere. The argument on is either 1 or 0.
read
Sample the value of tdo.
write tck tms tdi
Set the value of tck, tms, and tdi.
reset trst srst
Set the value of trst, srst.
An additional function, quit, is added to the remote_bitbang interface to
indicate there will be no more requests and the connection with the remote
driver should be closed.
These five functions are encoded in ASCII by assigning a single character to
each possible request. The assignments are:
B - Blink on
b - Blink off
R - Read request
Q - Quit request
0 - Write 0 0 0
1 - Write 0 0 1
2 - Write 0 1 0
3 - Write 0 1 1
4 - Write 1 0 0
5 - Write 1 0 1
6 - Write 1 1 0
7 - Write 1 1 1
r - Reset 0 0
s - Reset 0 1
t - Reset 1 0
u - Reset 1 1
The read response is encoded in ASCII as either digit 0 or 1.
*/