参数资料
型号: MA17503
厂商: Dynex Semiconductor Ltd.
英文描述: Radiation Hard MIL-STD-1750A Interrupt Unit
中文描述: 辐射硬的MIL - STD - 1750A中断组
文件页数: 9/34页
文件大小: 373K
代理商: MA17503
MA17503
9/34
3.9 TIMER CONTROL
These Timer Control inputs allow external control of Timers
A and B, the Trigger-Go Counter, and the Bus Fault Timeout
circuitry.
3.9 1 Disable Timers (DTIMERN)
Input. A low to this input disables Timers A and B and the
Trigger-Go counter, and also disables DMA access by forcing
DMAE low and DMAKN high. Raising DTIMERN high causes
Timers A and B and the Trigger-Go counter to resume counting
where they were stopped, and also allows normal DMA
operations.
3.9.2 Disable Bus-Fault Timeout (DTON)
Input. A low to this input will reset and disable the Busfault
timeout circuitry.
3.10 DISCRETES
Four discrete outputs are provided for system use, all of
which are enabled or disabled or both via internal l/O
commands.
3.10.1 Trigger-Go Timer Overflow (TGON)
Output. This output drops low whenever the Trigger-Go
counter overflows (rolls over to 0000). lt returns high when the
Trigger-Go counter is reset by software using the GO internal
l/O command.
3.10.2 Normal Power-Up Indicator (NPU)
Output. This output is brought low via internal I/O command
during module initialization as the first step of BlT. lf BIT is
completed successfully, NPU is raised high via microcode, and
remains high until reset by software via the RNS internal I/O
command.
START-UP ROM ENABLE (SURE)
Output. This output is used to enable an externally
implemented Start-Up ROM. SURE is brought high via the
execution of the ESUR internal l/O command (done by
microcode during initialization or by software), and remains
high until it is reset by software by using the DSUR internal l/O
command. While SURE is high, all memory reads shall access
main memory. This feature is utilized via the MOV instruction to
effect a non-volatile memory program transfer to faster
program execution RAM.
CONFIGURATION WORD ENABLE (CONFWN)
Output. This output is brought low during the data portion of
an RCW (Read Configuration Word) internal l/O operation. lt is
used as an output enable strobe for the externally implemented
Configuration Register. Because RCW is an internal I/O
command, the read cycle is a fixed six (EU)OSC cycles and is
terminated by IRDYN low. RDYN must not be asserted during
execution of this command.
4.0 OPERATING MODES
The following discussions detail the MAS281 chip set
operating modes from the perspective of the Interrupt Unit. The
MAS281 operating modes involving the MA17503 are: (1)
initialization, (2) instruction execution, (3) interrupt servicing,
(4) fault servicing, (5) DMA support, (6) Hold support, and (7)
timer operations.
4.1 INITIALISATION
A microcoded initialisation sequence is executed by the
chip set in response to a hardware reset. This routine, as
applicable to the lnterrupt Unit, disables and masks interrupts,
zeroes the Fault register, performs the MAS281 Integrated
Built-ln Test (BIT), raises the Start-Up ROM enable discrete
(SURE), clears and starts timers A and B, resets the Trigger-Go
counter, and disables DMA access. The resulting initialised
state of the MA17503 is listed in Table 3.
The microcoded BIT exercises all legal microinstruction bit
combinations and tests all internally accessible structures of
the MAS281 chip set. For the Interrupt Unit this includes the
MK, Pl, and FT registers, Interrupt Enable/Disable, and Timers
A and B. Table 4 details the tests performed by each of the five
BlT routines.
If any part of BIT fails, an error code identifying the failed
subroutine is loaded into FT bits 13-15, BlT is aborted with NPU
left in the low state, initialization is completed, and instruction
execution begins at address zero. The coding of the BIT results
is shown in Table 4.
NOTE:
To complete initialization and pass BIT, interrupt
and fault inputs must be high for the duration of the initialization
routine. ln addition, timers A and B must be clocked for BlT
success.
Item
Status
Fault (FT)
Pending Interrupt (Pl)
Mask (MK)
Interrupts
DMA Access
Timer A
Timer B
Trigger-Go Timer
Zeroed
Zeroed
Zeroed
Disabled
Disabled
Reset and Started
Reset and Started
Reset and Started
Table 3: Interrupt Initialisation State
相关PDF资料
PDF描述
MA1916 Radiation Hard Reed-Solomon & Convolution Encoder
MA28139 OBDH Bus Terminal
MA28140 Packet Telecommand Decoder
MA28151 Radiation hard Programmable Communication Interface
MA28155 Radiation Hard Programmable Peripheral Interface
相关代理商/技术参数
参数描述
MA1751E12B1+6-FSR-EM 制造商:Mechatronics Fan Group 功能描述:
MA1751E12B-FSR 功能描述:FAN AXIAL 172X150X51MM 12VDC 制造商:mechatronics fan group 系列:MA1751 零件状态:有效 电压 - 额定:12VDC 大小/尺寸:矩形/圆形 - 172mm 长 x 150mm 高 宽度:50.80mm 气流:269.2 CFM(7.62m3/min) 静压力:0.670 英寸水柱(166.9 Pa) 轴承类型:滚珠 风扇类型:管轴式 特性:- 噪声:61 dB(A) 功率(W):- RPM:3150 RPM 端接:2 引线 侵入防护:- 工作温度:- 认可:UL 额定电流:2.2A 电压范围:- 材料 - 框架:铝 材料 - 刀片:聚对苯二甲酸丁二酯(PBT) 重量:1.6 磅(725.7g) 标准包装:20
MA1751E24B-FSR 功能描述:AXIAL FAN 172X150X51MM 24VDC 制造商:mechatronics fan group 系列:* 零件状态:在售 标准包装:1
MA1751E48B2-FSR-TTL 功能描述:AXIAL FAN 172X150X51MM 48VDC LOC 制造商:mechatronics fan group 系列:* 零件状态:在售 标准包装:1
MA1751H24B1+6-FSR 功能描述:AXIAL FAN 172X150X51MM 24VDC TAC 制造商:mechatronics fan group 系列:* 零件状态:在售 标准包装:1