Glasgow Embedded / Glasgow - History

WIP: firmware: guard I2C transactions with timeouts.

If we don't add timeouts on I2C transactions, then the USB request
that caused it (for reads) or the next USB control request (for
writes) will silently hang forever until the device is power cycled.

This is clearly undesirable. However, this does not happen at all
during normal operation, and although it hardens the device, the FX2
firmware size comes at a premium, and blindly spraying these guard
conditions adds a nontrivial increase.

Therefore this code, although tested, is not currently used.

applet.i2c_master: require revC+.

The I2CPadsWrapper hack was horrible to use even when it worked.
I can't in good conscience recommenda anyone with a revA/B do that,
so let's get rid of it.

firmware: persist voltage limit on writes, not reads.

Oops... this would have written the EEPROM on each `glasgow voltage`
invocation.

applet.jtag: enumerate-ir: make more robust to missing DRs.

A missing DR is a DR that leaves TDO unconnected when it is selected.

applet.jtag_mips: update the lists of tested configurations.

applet.jtag: enumerate-ir: handle incorrect TAP selection.

applet.jtag: reset TAP chain before selecting a TAP.

Selecting a TAP requires reading IDCODE/BYPASS from DR, which means
that a TAP chain reset was a precondition for select_tap(), but this
wasn't intended or documented. The current design requires a reset,
so just add that.

Since all derived applets want to select a TAP, remove the TAP reset
via TMS from run(); however, keep TAP reset via TRST#, because that
enables the TRST# driver.