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SYS Registers
1.16.2 SYSJMBC Register
JTAG Mailbox Control Register
Figure 1-11. SYSJMBC Register
15
14
13
12
11
10
9
8
Reserved
r0
r0
r0
r0
r0
r0
r0
r0
7
6
5
4
3
2
1
0
JMBCLR1OFF
JMBCLR0OFF
Reserved
JMBM0DE
JMBOUT1FG
JMBOUT0FG
JMBIN1FG
JMBIN0FG
rw-(0)
rw-(0)
r0
rw-0
r-(1)
r-(1)
rw-(0)
rw-(0)
Table 1-17. SYSJMBC Register Description
Bit
Field
Type
Reset
Description
15-8
Reserved
R
0h
Reserved. Always reads as 0.
7
JMBCLR1OFF
RW
0h
Incoming JTAG Mailbox 1 flag auto-clear disable
0b = JMBIN1FG cleared on read of JMB1IN register
1b = JMBIN1FG cleared by software
6
JMBCLR0OFF
RW
0h
Incoming JTAG Mailbox 0 flag auto-clear disable
0b = JMBIN0FG cleared on read of JMB0IN register
1b = JMBIN0FG cleared by software
5
Reserved
R
0h
Reserved. Always reads as 0.
4
JMBMODE
RW
0h
This bit defines the operation mode of JMB for JMBI0/1 and JMBO0/1. Before
switching this bit, pad and flush out any partial content to avoid data drops.
0b = 16-bit transfers using JMBO0 and JMBI0 only
1b = 32-bit transfers using JMBO0 with JMBO1 and JMBI0 with JMBI1
3
JMBOUT1FG
R
1h
Outgoing JTAG Mailbox 1 flag. This bit is cleared automatically when a message
is written to the upper byte of JMBO1 or as word access (by the CPU, DMA,…)
and is set after the message was read via JTAG.
0b = JMBO1 is not ready to receive new data.
1b = JMBO1 is ready to receive new data.
2
JMBOUT0FG
R
1h
Outgoing JTAG Mailbox 0 flag. This bit is cleared automatically when a message
is written to the upper byte of JMBO0 or as word access (by the CPU, DMA,…)
and is set after the message was read via JTAG.
0b = JMBO0 is not ready to receive new data.
1b = JMBO0 is ready to receive new data.
1
JMBIN1FG
RW
0h
Incoming JTAG Mailbox 1 flag. This bit is set when a new message (provided via
JTAG) is available in JMBI1. This flag is cleared automatically on read of JMBI1
when JMBCLR1OFF = 0 (auto clear mode). On JMBCLR1OFF = 1, JMBIN1FG
needs to be cleared by SW.
0b = JMBI1 has no new data.
1b = JMBI1 has new data available.
0
JMBIN0FG
RW
0h
Incoming JTAG Mailbox 0 flag. This bit is set when a new message (provided via
JTAG) is available in JMBI0. This flag is cleared automatically on read of JMBI0
when JMBCLR0OFF = 0 (auto clear mode). On JMBCLR0OFF = 1, JMBIN0FG
needs to be cleared by SW.
0b = JMBI1 has no new data.
1b = JMBI1 has new data available.
56
System Resets, Interrupts, and Operating Modes, System Control Module
SLAU272C – May 2011 – Revised November 2013
(SYS)
Copyright © 2011–2013, Texas Instruments Incorporated