MCIMX286CVM4B Freescale Semiconductor, MCIMX286CVM4B Datasheet - Page 534

• Manufacturer Part Number: MCIMX286CVM4B
• Description: IC MPU I.MX286 289MAPBGA
• Manufacturer: Freescale Semiconductor
• Series: i.MX28r

Specifications of MCIMX286CVM4B

• Core Processor: ARM9
• Core Size: 32-Bit
• Speed: 454MHz
• Connectivity: CAN, EBI/EMI, Ethernet, I²C, MMC, SmartCard, SPI, SSI, UART/USART, USB OTG
• Peripherals: DMA, I²S, LCD, POR, PWM, WDT
• Program Memory Size: 128KB (32K x 32)
• Program Memory Type: Mask ROM
• Ram Size: 32K x 32
• Voltage - Supply (vcc/vdd): 1.25 V ~ 5.25 V
• Data Converters: A/D 17x12b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 289-LFBGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Number Of I /o: -
• Eeprom Size: -
• Lead Free Status / Rohs Status: Compliant

Programmable Registers
7.5.17 APBX DMA Channel 1 Semaphore Register
The APBX DMA Channel 1 semaphore register is used to synchronize between the CPU
instruction stream and the DMA chain processing state.
Each DMA channel has an 8 bit counting semaphore used to synchronize between the
program stream and the DMA chain processing. DMA processing continues until the DMA
attempts to decrement a semaphore which has already reached a value of zero. When the
attempt is made, the DMA channel is stalled until software increments the semaphore count.
EXAMPLE
BF_WR(APBX_CHn_SEMA, 1, INCREMENT_SEMA, 2);
current_sema = BF_RD(APBX_CHn_SEMA, 1, PHORE);
Address:
Re-
534
set
Bit
W
R
INCREMENT_
ADDRESS
31
0
PHORE
RSVD2
RSVD1
31 24
23 16
SEMA
Field
31 0
Field
15 8
7 0
30
0
29
0
(HW_APBX_CH1_SEMA)
HW_APBX_CH1_SEMA
RSVD2
28
0
Address of system memory buffer to be read or written over the AHB bus.
Reserved, always set to zero.
This read-only field shows the current (instantaneous) value of the semaphore counter.
Reserved, always set to zero.
The value written to this field is added to the semaphore count in an atomic way such that simultaneous
software adds and DMA hardware substracts happening on the same clock are protected. This bit field reads
back a value of 0x00. Writing a value of 0x02 increments the semaphore count by two, unless the DMA
channel decrements the count on the same clock, then the count is incremented by a net one.
27
0
26
0
i.MX28 Applications Processor Reference Manual, Rev. 1, 2010
25
0
24
0
HW_APBX_CH1_SEMA field descriptions
HW_APBX_CH1_BAR field descriptions
23
0
22
0
8002_4000h base + 1B0h offset = 8002_41B0h
21
0
PHORE
20
0
19
0
18
0
17
0
16
0
// increment semaphore by two
// get instantaneous value
15
0
Description
Description
14
0
13
0
RSVD1
12
0
11
0
10
0
0
9
0
8
Freescale Semiconductor, Inc.
0
7
INCREMENT_SEMA
0
6
0
5
0
4
3
0
0
2
0
1
0
0