QSPI Flash Programming with the Promira Serial…

Quad SPI (QSPI) flash programming uses four data lines instead of the standard single MOSI/MISO pair, enabling 4x the data throughput for the same clock frequency. The Promira Serial Platform supports Quad SPI and Dual SPI modes at clock speeds up to 80 MHz, making it the fastest host adapter in the Total Phase lineup for flash programming applications. Combined with Flash Center Software’s GUI-based programming interface, the Promira delivers production-grade QSPI flash programming without writing a single line of code.

Hardware Setup

For this example, we use a Micron N25Q032A, a 32 Mbit (4 MB) QSPI flash that operates at 1.8V. The Promira’s integrated level shifting handles the voltage translation from the host PC’s USB interface to the 1.8V I/O required by the flash device.

Connection

Connect the Promira to the flash target via a 10-pin or 34-pin ribbon cable. For QSPI operation, the Promira uses four data lines:

Promira Pin	Signal	Flash Pin
SCLK	SPI Clock	CLK
MOSI/IO0	Data 0	DQ0
MISO/IO1	Data 1	DQ1
IO2	Data 2	DQ2
IO3	Data 3	DQ3
SS	Chip Select	CS#
GND	Ground	VSS

Promira Configuration

1. Host interface: Connect via USB (bench use) or Ethernet (production floor).
2. I/O voltage: Set the supplementary I/O power to 1.8V in the Promira configuration utility, this sets the level shifter output voltage.
3. Target power: Enable target power if the flash device is not otherwise powered.
4. SPI mode: Set to Quad I/O in Flash Center.

Flash Center Programming Workflow

1. Select Target Device

In Flash Center, navigate to Operations > Select Target. The built-in device database includes the N25Q032A and thousands of other SPI and QSPI flash devices. Flash Center automatically configures the correct command set, page size, sector size, and timing parameters for the selected device.

2. Choose Operation

Flash Center supports several programming modes:

Mode	Description
Program + Verify	Write data and read back to confirm (recommended)
Program (with erase)	Erase sectors before programming
Program (no erase)	Write without prior erase (for pre-erased devices)
Read	Read flash contents to file
Verify	Compare flash contents against a reference file
Erase	Sector or chip erase

3. Execute

Select your firmware binary file and click Execute. Flash Center handles the complete programming sequence automatically:

1. Erase: issues Sector Erase (0xD8) commands for each 64 KB sector that will be written.
2. Program: uses Quad Input Fast Program (0x32) to write data in 256-byte pages across all four data lines simultaneously.
3. Verify: uses Quad Output Fast Read (0x6B) to read back the programmed data and compare byte-by-byte against the source file.

Key N25Q032A Parameters

Parameter	Value
Capacity	32 Mbit (4 MB)
Sectors	64 (64 KB each)
Subsectors	1,024 (4 KB each)
Page Size	256 bytes
Write Enable	0x06 (required before every program/erase)
Quad Input Fast Program	0x32
Quad Output Fast Read	0x6B

Why Promira for QSPI

The Promira’s 80 MHz SPI clock with Quad I/O delivers a theoretical data throughput of 40 MB/s (80 MHz x 4 bits / 8 bits per byte). In practice, throughput is limited by the flash device’s page program time and the overhead of erase operations, but the Promira’s pipelined queue architecture minimizes host-side latency between pages.

For teams that have been using the Aardvark (8 MHz, standard SPI only) or Cheetah (40+ MHz, standard SPI only), the Promira’s Quad SPI capability represents a significant productivity improvement for flash programming workflows, particularly for devices with large firmware images (multi-megabyte) that benefit from the 4x data lane parallelism.

GSAS Micro Systems provides the Promira Serial Platform with guidance on SPI Active application licensing (Level 1/2/3), flash target device selection, and production programming fixture integration for manufacturing teams across India.