PSD834F2-90MI STMicroelectronics, PSD834F2-90MI Datasheet - Page 23

• Manufacturer Part Number: PSD834F2-90MI
• Description: IC FLASH 2MBIT 90NS 52QFP
• Manufacturer: STMicroelectronics

Specifications of PSD834F2-90MI

• Format - Memory: FLASH
• Memory Type: FLASH
• Memory Size: 2M (256K x 8)
• Speed: 90ns
• Interface: Parallel
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 52-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-2009

Reading the Erase/Program Status Bits
The PSD provides several status bits to be used
by the MCU to confirm the completion of an Erase
or Program cycle of Flash memory. These status
bits minimize the time that the MCU spends per-
forming these tasks and are defined in Table 10.
The status bits can be read as many times as
needed.
Table 10. Status Bit
Note: 1. X = Not guaranteed value, can be read either '1' or ’0.’
Flash Memory
Functional Block
2. DQ7-DQ0 represent the Data Bus bits, D7-D0.
3. FS0-FS7 and CSBOOT0-CSBOOT3 are active High.
V
IH
FS0-FS7/CSBOOT0-
CSBOOT3
Doc ID 10552 Rev 3
Data
Polling
DQ7
Toggle
Flag
DQ6
For Flash memory, the MCU can perform a READ
operation to obtain these status bits while an
Erase or Program instruction is being executed by
the embedded algorithm. See the section entitled
PROGRAMMING FLASH MEMORY, page 25
details.
Error
Flag
DQ5
X
DQ4
Erase
Time-
out
PSD813F2V, PSD854F2V
DQ3
X
DQ2
X
DQ1
X
23/109
DQ0
for